WO2020049599A1

WO2020049599A1 - Process for the preparation of 4-(4-{[2-(4-chlorophenyl)-4,4-dimethylcyclohex-1-en-1- yl]methyl}piperazin-1-yl)-n-({3-nitro-4-[(tetrahydro-2h-pyran-4-ylmethyl)amino] phenyl}sulfonyl)-2-(1h-pyrrolo[2,3-b]pyridin-5-yloxy)benzamide)

Info

Publication number: WO2020049599A1
Application number: PCT/IN2019/050651
Authority: WO
Inventors: Thirumalai Rajan Srinivasan; Eswaraiah Sajja; Venkata Panakala Rao Gogulapati; Rajeshwar Reddy Sagyam; Srinivasulu Rangineni; Purna Chandrasekhar Reddy Thippireddy
Original assignee: Msn Laboratories Private Limited, R&D Center
Priority date: 2018-09-07
Filing date: 2019-09-09
Publication date: 2020-03-12

Abstract

The present invention relates to novel crystalline forms of 4-(4-{[2-(4-chlorophenyl)-4,4-dimethylcyclohex-1-en-1-yl]methyl}piperazin-1-yl)-N-({3-nitro-4-[(tetrahydro-2H-pyran -4-ylmethyl)amino]phenyl}sulfonyl)-2-(1H-pyrrolo[2,3-b]pyridin-5-yloxy)benzamide compound of formula-1 represented by the following structural formula-1, which is referred to as Venetoclax Formula-1 The present invention also relates to an improved process for the preparation of Venetoclax compound of formula-1 which is free of Impurity-I, Impurity-II, Impurity-III and Impurity-IV.

Description

Process for the preparation of 4-(4-ir2-(4-chlorophenyl)-4.4-dimethylcvclohex-l-en-l- yllmethvDpiperazin-l-yl)-N- nitro-4-r(tetrahvdro-2H-pyran-4-ylmethyl)aminol

phenyl)sulfonyl)-2-(lH-pyrrolor2,3-blpyridin-5-yloxy)benzamide)

Related Application:

This application claims the benefit of priority of our Indian patent application number 201841033808 filed on 07^th Nov. 2018 which is incorporated herein by reference.

Field of the Invention:

The present invention relates to novel crystalline forms of 4-(4- { [2-(4-chlorophenyl)- 4,4-dimethylcyclohex- l-en- 1 -yl] methyl jpiperazin- 1 -yl)-N-( { 3-nitro-4-[(tetrahydro-2H-pyran -4-ylmethyl)amino]phenyl}sulfonyl)-2-(lH-pyrrolo[2,3-b]pyridin-5-yloxy)benzamide represented by the following structural formula- 1, which is referred to as Venetoclax

Formula- 1

The present invention also relates to an improved process for the preparation of Venetoclax.

Background of the Invention:

Venetoclax is chemically known as 4-(4- { [2-(4-chlorophenyl)-4,4-dimethylcyclohex- l-en- l-yl]methyl jpiperazin- 1 -yl)-N-( { 3-nitro-4-[(tetrahydro-2H-pyran-4-ylmethyl)amino] phenylsulfonyl)-2-(lH-pyrrolo[2,3-b]pyridin-5-yloxy)benzamide.

Venetoclax a selective and orally bioavailable small-molecule inhibitor of BCL-2, an anti-apoptotic protein. Over expression of BCL-2 has been demonstrated in CLL cells where it mediates tumor cell survival and has been associated with resistance to chemo therapeutics. Venetoclax helps restore the process of apoptosis by binding directly to the BCL-2 protein, displacing pro-apoptotic proteins like BIM, triggering mitochondrial outer membrane permeabilization and the activation of caspases.

Venetoclax is approved in US as Venclexta tablet for oral administration for the treatment of patients with chronic lymphocytic leukemia with 17r deletion, as detected by an FDA approved test, who have received at least one prior therapy. This indication is approved under accelerated approval based on overall response rate.

US 8546399 B2 described Venetoclax or a pharmaceutically acceptable salt thereof (herein after referred as US‘399).

WO2012/071336 Al describes various crystalline forms A, B, C and D including anhydrate, hydrated, solvated, non-solvated and salt forms of Venetoclax compound of formula- 1.

WO2012/058392 Al describes solid dispersions comprising Venetoclax.

Polymorphism is the occurrence of different crystalline forms of a single compound and it is a property of some compounds and complexes. Thus, polymorphs are distinct solids sharing the same molecular formula, yet each polymorph may have distinct physical properties. Therefore, a single compound may give rise to a variety of polymorphic forms where each form has different and distinct physical properties, such as different solubility profiles, different melting point temperatures and/or different x-ray diffraction peaks. Since the solubility of each polymorph may vary, identifying the existence of pharmaceutical polymorphs is essential for providing pharmaceuticals with predicable solubility profiles. It is desirable to investigate all solid state forms of a drug, including all polymorphic forms, and to determine the stability, dissolution and flow properties of each polymorphic form.

Polymorphic forms of a compound can be distinguished in a laboratory by X-ray diffraction spectroscopy and by other methods such as, infrared spectrometry. Additionally, polymorphic forms of the same drug substance or active pharmaceutical ingredient, can be administered by itself or formulated as a drug product (also known as the final or finished dosage form), and are well known in the pharmaceutical art to affect, for example, the solubility, stability, flowability, tractability and compressibility of drug substances and the safety and efficacy of drug products.

US‘399 also describe process for the preparation of Venetoclax which is shown in the scheme given below:

Venetoclax

US‘399 patent describes process for the preparation of Venetoclax. The said process provides Venetoclax which is contaminated with impurities.

Pharmaceutical products for administration to subjects such as humans must contain high purity drug substance preparations and pharmaceutical compositions, and be formulated into dosage forms that contain consistent amounts of an active pharmaceutical ingredient (API).

All drug substance preparations, regardless of the API, contain varying amounts of impurities. These impurities can generally be grouped into categories based on their chemical identity and include“product-related impurities”, i.e., impurities that are structurally similar to the API (e.g., enantiomers) and“process-related impurities”, i.e. impurities introduced by or resulting from the processes used to make the API.

According to the present invention, provides alternative process for preparing Venetoclax which is simple, eco-friendly, cost-effective, robust and well-suited for use on an industrial scale.

Brief description of the Invention:

First embodiment of the present invention provides a process for the preparation of 3- nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)benzenesulfonamide compound of formula- III comprising reacting 4-chloro-3-nitrobenzenesulfonamide compound of formula-I with (tetrahydro-2H-pyran-4-yl)methanamine compound of formula-II in the presence of base and solvent to provide 3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)benzene sulfonamide compound of formula-III.

Second embodiment of the present invention provides a process for the preparation of 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 comprising reacting compound of formula-2 with phosphoryl chloride and dimethylformamide in the presence of organic solvents.

Third embodiment of the present invention provides a process for the preparation of 4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-carbaldehyde compound of formula-4 comprising reacting 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 with 4-chlorophenyl boronic acid or its esters in the presence of palladium catalyst and a base in a solvent at a suitable temperature to provide compound of formula-4. Fourth embodiment of the present invention provides a process for preparation of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6- tetrahydro-[ 1,1 '-biphenyl] -2-yl)methyl)piperazin-l-yl)benzoate compound of formula-8 comprising:

a) treating l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl) piperazine hydrochloride compound of formula-6 with a base in a solvent to provide 1- ((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazine compound of formula-IV,

b) reacting the compound of formula-IV with methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl) oxy)-4-fluorobenzoate compound of formula-7 in the presence of dipotassium hydrogen phosphate in a solvent to provide 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4- (4-((4'-chloro-5 ,5 -dimethyl-3 ,4,5 ,6-tetrahydro- [ 1 , 1 '-biphenyl] -2-yl)methyl)piperazin- 1 - yl)benzoate compound of formula-8,

c) purifying compound of formula- 8 with a solvent to provide pure compound of formula-

8.

Fifth embodiment of the present invention provides a process for the purification of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetra hydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoate compound of formula-8 comprising dissolving / suspending compound of formula-8 in a solvent and isolating pure compound of formula-8.

Sixth embodiment of the present invention provides a process for the purification of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro- [ 1, 1 '-biphenyl] -2-yl)methyl)piperazin-l-yl)benzoic acid compound of formula-9 comprising dissolving compound of formula-9 in a solvent and isolating pure compound of formula-9.

Seventh embodiment of the present invention provides a process for the preparation of Venetoclax which is free of impurities herein after referred to as Impurity-I, Impurity-II, Impurity-III and Impurity-IV. Eight embodiment of the present invention provides a process for the purification of compound of formula-5.

Ninth embodiment of the present invention relates crystalline form of Venetoclax herein after referred as form-N 1.

Tenth embodiment of the present invention provides a process for the preparation of crystalline form-N 1 of Venetoclax comprising dissolving Venetoclax in a solvent to provide a solution of Venetoclax and isolating crystalline form-Nl of Venetoclax.

Eleventh embodiment of the present invention relates crystalline form of Venetoclax herein after referred as form-N2.

Twelfth embodiment of the present invention provides a process for the preparation of crystalline form-N2 of Venetoclax comprising dissolving Venetoclax in a solvent to provide a solution of Venetoclax and isolating crystalline form-N2 of Venetoclax.

Thirteenth embodiment of the present invention relates to crystalline form of Venetoclax, hereinafter designated as Form-M.

Fourteenth embodiment of the present invention provides a process for the preparation crystalline form-M of Venetoclax.

Fifteenth embodiment of the present invention provides crystalline form of Venetoclax tetrahydrofuran, hereinafter designated as Form-Sl.

Sixteenth embodiment of the present invention provides a process for the preparation of crystalline form-S l of Venetoclax tetrahydrofuran.

Seventeenth embodiment of the present invention provides Venetoclax xylene.

Eighteenth embodiment of the present invention provides a process for the preparation of Venetoclax xylene. Nineteenth embodiment of the present invention provides Venetoclax nitro methane.

Twentieth embodiment of the present invention provides a process for the preparation of Venetoclax nitro methane.

Twenty-first embodiment of the present invention provides Venetoclax vinyl acetate.

Twenty-second embodiment of the present invention provides a process for the preparation of Venetoclax vinyl acetate.

Twenty-third embodiment of the present invention provides Venetoclax isopropyl acetate.

Twenty-fourth embodiment of the present invention provides a process for the preparation of Venetoclax isopropyl acetate.

Twenty-fifth embodiment of the present invention provides Venetoclax methyl acetate.

Twenty-sixth embodiment of the present invention provides a process for the preparation of Venetoclax methyl acetate.

Brief description of Drawings:

Figure 1: Illustrates the PXRD pattern of crystalline form-M of Venetoclax free base.

Figure 2: Illustrates the PXRD pattern of crystalline form-Sl of Venetoclax tetrahydrofuran. Figure 3: Illustrates the PXRD pattern of crystalline form-S2 of Venetoclax xylene.

Figure 4: Illustrates the PXRD pattern of crystalline from-S3 of Venetoclax nitro methane. Figure 5: Illustrates the PXRD pattern of crystalline form-S4 of Venetoclax vinyl acetate. Figure 6: Illustrates the PXRD pattern of crystalline form-S5 of Venetoclax isopropyl acetate.

Figure 7: Illustrates the PXRD pattern of crystalline form-S6 of Venetoclax methyl acetate

Figure 8: Illustrates the PXRD pattern of crystalline form-Nl of Venetoclax.

Figure 9: Illustrates the PXRD pattern of crystalline form-N2 of Venetoclax. Detailed description of the Invention:

The term“suitable solvent” used in the present invention refers to“hydrocarbon solvents” such as n-hexane, n-heptane, cyclohexane, pet ether, benzene, toluene, n-pentane, cycloheptane, methylcyclohexane, m-, o-, or p-xylene and the like;“ether solvents” such as dime thoxyme thane, tetrahydrofuran, l,3-dioxane, l,4-dioxane, furan, diethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol dimethyl ether, anisole, t-butyl methyl ether, 1 ,2-dimethoxy ethane and the like;“ester solvents” such as methyl acetate, ethyl acetate, isopropyl acetate, n-butyl acetate and the like; “polar-aprotic solvents such as dimethylacetamide (DMA), dimethylformamide (DMF), dimethylsulfoxide (DMSO), N- methylpyrrolidone (NMP) and the like; “chloro solvents” such as dichloromethane, dichloroethane, chloroform, carbon tetrachloride and the like; “ketone solvents” such as acetone, methyl ethyl ketone, methyl isobutylketone and the like;“nitrile solvents” such as acetonitrile, propionitrile, isobutyronitrile and the like; “alcoholic solvents” such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 2-nitroethanol, 2-fluoroethanol, 2,2,2-trifluoroethanol, ethylene glycol, 2-methoxyethanol, 1, 2- ethoxyethanol, diethylene glycol, 1, 2, or 3-pentanol, neo-pentyl alcohol, t-pentyl alcohol, diethylene glycol monoethyl ether, cyclohexanol, benzyl alcohol, phenol, or glycerol and the like;“polar solvents” such as water or mixtures thereof.

The term“suitable base” used herein the present invention until unless specified is selected from inorganic bases like“alkali metal hydroxides” such as lithium hydroxide, sodium hydroxide, potassium hydroxide and the like;“alkali metal carbonates” such as sodium carbonate, potassium carbonate, lithium carbonate and the like; “alkali metal bicarbonates” such as sodium bicarbonate, potassium bicarbonate, lithium bicarbonate and the like;“alkali metal hydrides” such as potassium hydride, lithium hydride and the like; “alkali metal alkoxides” such as sodium methoxide, sodium ethoxide, sodium tert-butoxide, potassium methoxide, potassium ethoxide, potassium tert-butoxide and the like; ammonia; and organic bases such as triethylamine, methylamine, ethylamine, l,8-diazabicyclo [5.4.0]undec-7-ene (DBU), l,5-diazabicyclo(4.3.0)non-5-ene (DBN), lithium dioisoporpyl amide (LDA), n-butyl lithium, tribenzylamine, isopropylamine, diisopropylamine, diiso propylethylamine, N-methylmorpholine, N-ethylmorpholine, piperidine, dimethyl aminopyridine, morpholine, pyridine, 2,6-lutidine, 2,4,6-collidine, imidazole, 1 -methyl imidazole, 1,2, 4-triazole, l,4-diazabicyclo[2.2.2]octane (DABCO) or mixtures thereof.

"Substantially pure" as used in the present invention herein refers to the purity of the material which is at least about 98.0 %, at least about 98.5 %, at least about 99.0 %, at least about 99.1 %, at least about 99.2 %, at least about 99.3 %, at least about 99.4 %, at least about 99.5 %, at least about 99.6 %, at least about 99.7 %, at least about 99.8 %, at least about 99.9 % or 100 % as measured by a liquid chromatography method.

First embodiment of the present invention provides a process for the preparation of 3- nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)benzenesulfonamide compound of formula- III comprising reacting 4-chloro-3-nitrobenzenesulfonamide compound of formula-I with (tetrahydro-2H-pyran-4-yl)methanamine compound of formula-II in the presence of base and solvent to provide 3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl) amino)benzene sulfonamide compound of formula-III.

Process for the preparation of compound of formula-III of the present invention is schematically represented as follows:

Formula-I Formula-III

In the process of the first embodiment the base is selected from organic or inorganic base preferably organic base such as triethyl amine and solvent is selected from alcohol solvents, nitrile solvents, ester solvents, chloro solvents, ketone solvents, ether solvents, water or mixture thereof.

Second embodiment of the present invention provides a process for the preparation of 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 comprising reacting 3,3-dimethylcyclohexanone compound of formula-2 with phosphoryl chloride and dime thy lformamide in the presence of organic solvents.

Process for the preparation of compound of formula-3 of the present invention is schematically represented as follows:

Formula-2 Formula-3

In the process of the second embodiment, the organic solvent is selected from alcohol solvents, nitrile solvents, ester solvents, hydrocarbon solvents, chloro solvents, ketone solvents, ether solvents, water or mixture thereof; preferably hydrocarbon solvents.

Third embodiment of the present invention provides a process for the preparation of 4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2-carbaldehyde compound of formula-4 comprising reacting 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 with 4-chlorophenyl boronic acid or its esters in the presence of palladium catalyst and a base in a solvent at a suitable temperature to provide compound of formula-4.

Process for the preparation of compound of formula-4 of the present invention is schematically represented as follows:

Water, Acetonitrile

Pd(PPh₃)₄, K₇CQ_{3 >}

4-Chlorophenyl boronic acid

Formula-3 Formula-4

In the process of the third embodiment the suitable palladium catalyst used is selected from 1 , 1 '-bis(diphenylphosphino)ferrocene]dichloropalladium(II)(Pd(dppf)Cl2), tetrakis(tri phenylphosphine) palladium (0) (Pd(PPh₃)4), palladium (Il)chloride (PdCl₂), bis(benzonitrile) palladium(II)dichloride (Pd(PhCN)2Cl2), bis(triphenylphosphine)palladium (II) dichloride (Pd(PPli3)2Cl2), and allyl palladium (II) chloride dimer (PdCl(C₃H5)]2). The suitable base is selected from organic or inorganic base. The suitable solvent is selected from alcohol solvents, nitrile solvents, ester solvents, chloro solvents, ketone solvents, ether solvents, water or mixture thereof.

In the process of the third embodiment, the temperature of the reaction is ranging from 30°C to l20°C; preferably at a temperature ranging from 70-75°C.

According to the prior art compound of formula-4 is prepared by reacting compound of formula-2 with 4-chlorophenyl boronic acid in the presence of palladium acetate. Using palladium acetate the reaction took longer time, incomplete and provided compound of formula-4 with low yield and hence decreases the productivity. Moreover palladium acetate is expensive reagent and not suggestible for commercial scale.

The present invention provide an alternate process for the preparation of compound of formula-4 by reacting compound of formula-2 with compound of formula-3 in the presence of tetrakis(triphenylphosphine) palladium at a temperature ranging from 70-75°C. It is observed that by maintaining the reaction temperature at 70-75°C the rate of the reaction was increased and completed the reaction in a shorter period of time i.e. within 3-4 hours and provided compound of formula-4 with good yield.

Moreover tetrakis(triphenylphosphine)palladium is cheaper when compared with palladium acetate.

Fourth embodiment of the present invention provides a process for preparation of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetra hydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoate compound of formula-8 comprising:

b) reacting compound of formula-IV with methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)- 4-fluorobenzoate compound of formula-7 in the presence of dipotassium hydrogen phosphate in a solvent to provide 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate compound of formula- 8,

c) purifying compound of formula-8 with a solvent to provide pure compound of formula-

8.

In the fourth embodiment of the present invention, wherein the suitable base used in step-a) is selected from organic or inorganic base; the suitable solvent used in step-a), b) and step-c) are selected from alcohol solvents, nitrile solvents, ester solvents, hydrocarbon solvents, polar aprotic solvents, chloro solvents, ketone solvents, ether solvents, water or mixture thereof.

In the process of the fifth embodiment, dissolving compound of formula-8 in a suitable solvent selected from alcohol solvents, hydrocarbon solvents and water or mixtures thereof at a suitable temperature ranging from 30°C and above to provide a solution of compound of formula-8.

Optionally, a solution of compound of formula-8 can be filtered to make it particle free

In the process of the fifth embodiment, isolating pure compound of formula-8 can be carried out by any methods known in the art or may be isolated by employing any of the techniques, but not limited to cooling, decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used and the like, and optionally washing with a solvent According to the prior art process compound of formula-8 is obtained with low purity and further using low pure compound of formula-8 in the next stages results in the decrease in the purity of the subsequent intermediate compounds as well as Venetoclax.

In order to get the pure compound, the present inventions have purified the compound of formula-8 using a mixture of alcohol solvents and hydrocarbon solvents preferably methanol and toluene. It has been found that the purity of compound of formula-8 had enormously increased from 80% to 95%.

In the process of the fifth embodiment, the pure compound of formula-8 is useful in the preparation of Pure Venetoclax.

Sixth embodiment of the present invention provides a process for the purification of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro- [l, r-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid compound of formula-9 comprising dissolving compound of formula-9 in a solvent and isolating pure compound of formula-9.

In the process of the sixth embodiment, dissolving compound of formula-9 in a solvent and dissolving of compound of formula-9 can be carried out by maintaining at 25- 30°C or optionally by heating to provide a solution of compound of formula-9.

Optionally, a solution of compound of formula-9 can be filtered to make it particle free.

In the process of the sixth embodiment, dissolving compound of formula-9 in a solvent selected from selected from nitrile solvents, ester solvents, hydrocarbon solvents, polar aprotic solvents, chloro solvents, ketone solvents, ether solvents, water, acetic acid, formic acid or mixture thereof.

In the process of the sixth embodiment, adding anti-solvent to a solution of compound of formula-9 and isolating pure compound of formula-9.

In the process of the sixth embodiment, anti-solvent is alcohol solvents; preferably isopropanol. According to the prior art process compound of formula-9 is obtained with low purity and further using low pure compound of formula-9 in the next stages results in the decrease in the purity of Venetoclax.

In order to get the pure compound, the present inventions have purified the compound of formula-9 using a mixture of formic acid and alcohol solvents preferably isopropanol. It has been found that the purity of compound of formula-9 had increased from 95% to 98%.

In the process of the fifth embodiment, the pure compound of formula-9 is useful in the preparation of Pure Venetoclax.

Seventh embodiment of the present invention provides a process for the preparation of Venetoclax which is free of impurities hereinafter referred to as Impurity-I, Impurity-II, Impurity-III and Impurity-IV, comprising:

a) Reacting 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 with 4-chlorophenyl boronic acid or its esters in the presence of palladium catalyst and a base in a solvent at a suitable temperature to provide compound of formula-4, b) reacting the compound of formula-4 with tert-butyl piperazine- 1 -carboxylate in the presence of sodium triacetoxyborohydride in tetrahydrofuran and toluene to provide tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl) piperazine- 1 -carboxylate compound of formula-5,

c) optionally purifying the compound of formula-5 using a solvent,

d) treating the compound of formula-5 with hydrochloric acid source in a solvent to provide l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl) piperazine hydrochloride compound of formula-6,

e) treating l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl) piperazine hydrochloride compound of formula-6 with a base in a solvent to provide 1- ((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazine compound of formula-IV,

f) reacting the compound of formula-IV with methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl) oxy)-4-fluorobenzoate compound of formula-7 in the presence of dipotassium hydrogen phosphate in a solvent to provide 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4- (4-((4'-chloro-5 ,5 -dimethyl-3 ,4,5 ,6-tetrahydro- [ 1 , 1 '-biphenyl] -2-yl)methyl)piperazin- 1 - yl)benzoate compound of formula-8,

g) optionally purifying the compound of formula-8 with a solvent to provide pure compound of formula- 8,

h) treating the compound of formula-8 with a base in a solvent to provide 2-((lH- pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r- biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid compound of formula- V followed by treating it with hydrochloric acid source to provide 2-((lH-pyrrolo[2,3-b]pyridin-5- yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl) piperazin- 1 -yl)benzoic acid hydrochloride compound of formula-9,

i) reacting the compound of formula-9 with 3-nitro-4-(((tetrahydro-2H-pyran-4-yl) methyl)amino)benzenesulfonamide compound of formula-III in the presence of coupling agent in a base in a solvent to provide Venetoclax compound of formula- 1, j) optionally purifying Venetoclax using a solvent to provide pure Venetoclax compound of formula- 1.

In the process of the seventh embodiment wherein in the suitable base used in step-a), e), h) and step-i) is selected from organic or inorganic base;

the suitable palladium catalyst used in step-a) is selected from 1 , r-bis(diphenylphosphino) ferrocene]dichloropalladium(II)(Pd(dppf)Cl2), tetrakis(triphenylphosphine) palladium (0) (Pd(PPh₃)4), palladium (II) chloride (PdCb), bis(benzonitrile) palladium(II)dichloride (Pd(PhCN)2Cl2), bis(triphenylphosphine)palladium (II) dichloride (PdiPPt_hbCb), and allyl palladium (II) chloride dimer (PdCKCsfhjb); the suitable temperature is ranging from 40°C to 1 l5°C; preferably at a temperature ranging from 70-75°C;

the suitable hydrochloric acid source used in step-d) and step-h) is selected from methanol- HC1, ethanol-HCl, isopropanol-HCl, hydrochloric acid, hydrochloric acid gas, aqueous hydrochloric acid; ethyl acetate -hydrochloric acid;

the suitable coupling agent is selected from in step-d) the suitable coupling agent is selected from thionyl chloride, (DCC) N,N-dicyclohexylcarbodimide, N,N'-diisopropylcarbodiimide, N-di-tert-butylcarbodiimide, 1 ,3-di-p-tolylcarbodiimide, bis(3-chloro-2-methylphenyl) carbodiimide, bis(otolylcarbodiimide), l-tert-butyl-3-ethylcarbodiimide, N-(3-dimethylamino propyl)-N'-ethylcarbodiimide, bis(2,6-diisopropylphenyl)carbodiimide, bis(2,6-diethylphenyl )carbodiimide, N-cyclohexyl-N'-isopropylcarbodiimide, N-methyl-N'-phenyl carbodiimide, l-cyclohexyl-3-(2-(4-morpholinyl)ethyl)carbodiimide, N,N'-dicyclohexyl-N-methylcarbodi imidium iodide, l-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC-HC1), ((0-benzotriazol-l-yl)-N,N,N',N'-tetramethyluroniumtetrafluoroborate) (TBTU), 2-chloro- 4,6-dimethoxy-l,3,5-triazine (CDMT), 2-chloro-l,3-dimethylimidazolium chloride (DMC), alkyl chloroformate compounds (e.g. ethyl chloroformate, isobutyl chloroformate (IBCf), or the like) and optionally, in addition to the coupling agent, a catalytic auxiliary nucleophile may be used to activate the carboxyl group.

Suitable catalytic auxiliary nucleophiles which can be used to promote the reaction include, but are not limited to 1 -hydroxybenzotriazole (HOBt), N-hydroxysuccinimede 5 (HOSu) and N-hydroxy-5-norbene-endo-2, 3 -dicarboxamide (HONB);

the suitable solvent used in step-a) to step-j) is selected from alcohol solvents, ester solvents, hydrocarbon solvents, ketone solvents, chloro solvents, ether solvents, nitrile solvents, polar aprotic solvents, water, formic acid, acetic acid or mixture thereof.

Eighth embodiment of the present invention provides a process for the purification of compound of formula-5 comprising of dissolving compound of formula-5 in a solvent and isolating to provide pure compound of formula-5.

In the process of the eighth embodiment, provides a process for the purification of compound of formula-5 comprising dissolving compound of formula-5 in solvents selected from ketone solvents, alcohol solvents, nitrile solvents, ester solvents, hydrocarbon solvents, chloro solvents, ether solvents, water or mixture thereof; preferably ketone solvents at a suitable temperature ranging from 30°C and above to provide a solution of compound of formula-5.

Optionally, the solution of compound of formula-5 can be filtered to make it particle free.

In the process of the eight embodiment, isolating pure compound of formula-5 by employing any of the techniques, but not limited to cooling, decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used and the like, and optionally washing with a solvent to provide pure compound of formula-5.

Regulatory authorities worldwide require that drug manufacturers isolate, identify and characterize the impurities in their products. Furthermore, it is required to control the levels of these impurities in the final drug compound obtained by the manufacturing process and to ensure that the impurity is present at the lowest possible levels, even if structural determination is not possible.

Thus, the active ingredient as well as pharmaceutical preparations made therefrom requires the presence of impurities well within the limits and should comply with regulatory guidance.

Venetoclax prepared according to the prior art processes is having low purity. This is because of Venetoclax obtained according to prior art processes is contaminated with impurities. Further after several purifications of Venetoclax these impurities were unable to remove from the Venetoclax.

After several optimizations, inventors of the present invention have identified the origin of these impurities and they have found that the impurities are formed by the condensation of compound of formula-4 with (4'-chloro-[l,l'-biphenyl]-4-yl)boronic acid or its ester to provide impurity-I.

Impurity-I

This impurity-I further retained in the compound of formula-4 and undergo reactions in the subsequent stages to provide 2-((lH-pyrrolo[2,3-b]pyridin-6-yl)oxy)-4-(4-((4"-chloro- 5,5-dimethyl-3,4,5,6-tetrahydro-[l,l':4', l"-terphenyl]-2-yl)methyl)piperazin-l-yl)-N-((3-nitro -4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)phenyl)sulfonyl)benzamide which is herein after referred as“Impurity-II”.

Further, upon self-condensation of compound of formula-5 lead to provide Impurity- III.

Boc

Impurity-III

This is retained in the compound of formula-5 and undergoes reactions in the subsequent stages to provide 4,4'-(4,4'-((4,4,5"',5"'-tetramethyl-3,3"',4,4"',5,5"',6,6"'-octa hydro-[l,l':4',l":4",l"'-quarterphenyl]-2,2"'-diyl)bis(methylene))bis(piperazine-4,l-diyl))bis (2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-N-((3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl) amino)phenyl)sulfonyl)benzamide) which is herein after referred as“Impurity-IV”.

These impurities-I and III are controlled to less than 0.05% as measured by HPLC in compound of formula-5 by purifying the compound of formula-5 using organic solvents selected from ketone solvents, alcohol solvents, nitrile solvents, ester solvents, hydrocarbon solvents, chloro solvents, ether solvents, water or mixture thereof; preferably ketone solvent. By controlling these impurities-I and III at very initial level in the manufacturing process inventors of the present invention were able to control the formation of impurity-II and impurity-IV to less than 0.05% in the final API and hence provided substantially pure Venetoclax.

In an embodiment, the present invention provides a process for the preparation of a substantially pure compound of formula-5, which is substantially free of impurity-I and impurity-III, comprising: purification of compound of formula-5 using a solvent. In the process of the eighth embodiment, the impurities-II and IV are characterized which are shown below:

In an embodiment, the present invention provides substantially pure Venetoclax, which is substantially free of impurity-I, Impurity-II, Impurity-III and Impurity-IV.

In an embodiment of the present invention provides substantially pure Venetoclax having purity of greater than about 99.9%; preferably greater than about 99.95%; more preferably greater than about 99.99% as measure by HPLC.

In the ninth embodiment of the present invention the PXRD pattern of crystalline form-Nl of Venetoclax is depicted in figure-8. Tenth embodiment of the present invention provides a process for the preparation of crystalline form-Nl of Venetoclax comprising dissolving Venetoclax in a solvent to provide a solution of Venetoclax and isolating crystalline form-Nl of Venetoclax.

In the process of the tenth embodiment, provides a process for the preparation of crystalline form-Nl of Venetoclax comprising dissolving Venetoclax in a suitable solvent selected from alcohol solvents, ketone solvents or mixtures thereof at a suitable temperature ranging from 30°C and above to provide a solution of Venetoclax.

Optionally, the solution of Venetoclax can be filtered to make it particle free.

In the process of the tenth embodiment, isolating crystalline form-Nl of Venetoclax by employing any of the techniques, but not limited to cooling, decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used and the like, and optionally washing with a solvent to provide crystalline form-Nl of Venetoclax.

In the eleventh embodiment of the present invention the PXRD pattern of crystalline form-N2 of Venetoclax is depicted in figure-9.

In the process of the twelfth embodiment, provides a process for the preparation of crystalline form-N2 of Venetoclax comprising dissolving Venetoclax in a suitable solvent selected from ether solvents, ketone solvents or mixtures thereof at a suitable temperature ranging from 30°C and above to provide a solution of Venetoclax.

Optionally, the solution of Venetoclax can be filtered to make it particle free. In the process of the tenth embodiment, isolating crystalline form-N2 of Venetoclax by employing any of the techniques, but not limited to cooling, decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used and the like, and optionally washing with a solvent to provide crystalline form-N2 of Venetoclax.

In an embodiment of the present invention, crystalline form-Nl and crystalline form- N2 are useful in the preparation of pure Venetoclax.

In an embodiment, the present invention provides a substantially pure Venetoclax, which is substantially free of the following impurities:

a) 3-Nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)benzenesulfonamide “Sulfonamide impurity”;

b) 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro- [l,r-biphenyl]-2-yl)methyl) piperazin- 1 -yl)benzoic acid hydrochloride“Acid impurity”; c) 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-fluoro-N-((3-nitro-4-(((tetrahydro-2H-pyran-4- yl)methyl)amino)phenyl)sulfonyl)benzamide“Fluoro sulfonamide impurity”;

d) Methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetra hydro- [ 1 , 1 '-biphenyl] -2-yl)methyl)piperazin- 1 -yl)benzoate“Ester impurity” ;

e) 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-bi phenyl]-2-yl)methyl)piperazin-l-yl)-N-((3-nitro-4-(((tetrahydro-2Hpyran-4-yl)methyl) amino)phenyl)sulfonyl)benzamide“Deschloro sulfonamide impurity”;

f) 4-(3-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(((3-nitro-4-((tetrahydro-2H-pyran-4-yl) methyl)amino)phenyl)sulfonyl)carbamoyl)phenyl)-l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetra hydro-[l,r-biphenyl]-2-yl)methyl)piperazine l-oxide“N-Oxide impurity” and

g) 2-((l-(2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetra hydro-[l,r-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoyl)-lHpyrrolo[2,3-b]pyridin-5-yl) oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl) piperazin- l-yl)-N-((3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)phenyl)sulfonyl) benzamide“Dimer impurity”.

In the thirteenth embodiment, the present invention provides crystalline form-M of Venetoclax characterized by its X-ray powder diffraction (XRD) pattern having peaks at about 4.6, 6.9 and 8.7 ± 0.2 degrees of 2-theta.

The crystalline form-M of Venetoclax is further characterized by its X-ray powder diffraction (XRD) pattern having peaks at about 10.3; 10.9; 13.9; 18.7 and 21.1 ± 0.2 degrees of 2-theta.

The crystalline form-M of Venetoclax is further characterized by its X-ray powder diffraction (XRD) pattern having peaks at about 9.2, 9.6, 10.3, 10.9, 11.3, 12.9, 13.3, 13.9, 14.3, 14.9, 15.2, 16.3, 16.7, 17.0, 17.6, 18.4, 18.7, 19.7, 19.8, 21.1, 21.6, 22.0, 22.6, 23.0, 24.0, 24.8, 25.7, 26.5, 28.2, 28.9 and 30.7 ± 0.2 degrees of 2-theta.

The crystalline Form-M of Venetoclax is further characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure- 1.

In the fourteenth embodiment, of the present invention provides a process for the preparation of crystalline form-M of Venetoclax, comprising contacting Venetoclax with a suitable organic solvent selected from alcohol solvents, ester solvents, hydrocarbon solvents, ketone solvents, ether solvents, chloro solvents, nitrile solvents and water or mixtures thereof and isolating crystalline form-M of Venetoclax.

In the process of the fourteenth embodiment, contacting Venetoclax with organic solvent can be carried out by suspending or dissolving Venetoclax in suitable organic solvent to provide a solution of Venetoclax.

Optionally the dissolution of Venetoclax in solvent can be made by heating the solution.

In the process of the fourteenth embodiment, Venetoclax can be dissolved in suitable organic solvent at a suitable temperature of about 30°C and above. Optionally, the solution of Venetoclax can be filtered to make it particle free.

In the process of the fourteenth embodiment, Venetoclax in organic solvent can be contacted with an organic solvent or water. Wherein, the organic solvent is selected from alcohol solvents, ester solvents, ketone solvents, nitrile solvents, ether solvents, chloro solvents, water or mixtures thereof.

In the process of the fourteenth embodiment, isolating crystalline form-M of Venetoclax can be carried out by any methods known in the art or crystalline form-M of Venetoclax can be isolated by employing any of the techniques, but not limited to: decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used and the like, and optionally washing with a solvent to provide crystalline form-M of Venetoclax.

In the process of the fourteenth embodiment, the crystalline form-M of Venetoclax can be dried in a suitable drying equipment such as tray dryer, vacuum oven, rotatory cone dryer, air oven, fluidized bed dryer, spin flash dryer, flash dryer, or the like. The drying can be carried out at atmospheric pressure or under reduced pressures at temperatures of less than about l00°C, less than about 60°C, less than about 40°C, or any other suitable temperatures. The drying can be carried out for any time period required for obtaining a desired quality, such as from about 15 minutes to 10 hours or longer.

In fifteenth embodiment, the present invention provides crystalline form-Sl of Venetoclax tetrahydrofuran is characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure-2.

In the sixteenth embodiment, the present invention provides a process for the preparation of crystalline form-Sl of Venetoclax tetrahydrofuran compound of formula- 1, comprising dissolving Venetoclax in tetrahydrofuran and adding Venetoclax in tetrahydrofuran to a suitable solvent and isolating the crystalline form-Sl of Venetoclax tetrahydrofuran .

In the process of the sixteenth embodiment, dissolving Venetoclax in a suitable organic solvent can be at a suitable temperature of about 30°C and above to provide a solution of Venetoclax. Optionally, the solution of Venetoclax can be filtered to make it particle free. In the process of the sixteenth embodiment wherein, the suitable solvent is selected from alcohols solvents, ester solvents, chloro solvents, ketone solvents, hydrocarbon solvents, polar aprotic solvents, nitrile solvents and polar solvents like water or mixture thereof;

In the process of the sixteenth embodiment, adding a solution of Venetoclax in tetrahydrofuran to a suitable solvent which can be pre -heated to provide crystalline form-S 1 of Venetoclax tetrahydrofuran.

In seventeenth embodiment, the present invention provides Venetoclax xylene.

In seventeenth aspect of the embodiment the crystalline form-S2 of Venetoclax xylene is characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure-3.

In eighteenth embodiment, the present invention provides a process for the preparation of crystalline form-S2 of Venetoclax xylene comprising dissolving Venetoclax in xylene and isolating crystalline form-S2 of Venetoclax xylene.

In the process of the eighteenth embodiment, dissolving Venetoclax in xylene can be at a suitable temperature of about 30°C and above. Optionally, the solution can be filtered to make it particle free.

In nineteenth embodiment, the present invention provides Venetoclax nitro methane.

In first aspect of the nineteenth embodiment the crystalline form-S3 of Venetoclax nitro methane is characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure-4.

In the twentieth embodiment, the present invention provides a process for the preparation of crystalline form-S3 of Venetoclax nitro methane comprising dissolving Venetoclax in nitro methane and isolating crystalline form-S3 of Venetoclax nitro methane. In the process of the twentieth embodiment, dissolving Venetoclax in nitro methane can be at a suitable temperature of about 30°C and above to provide a solution of Venetoclax. Optionally, the solution of Venetoclax can be filtered to make it particle free.

In the process of the twentieth embodiment, the solution of Venetoclax in nitro methane can be cooled to precipitate solid to a suitable temperature at which crystalline form-S3 of Venetoclax is formed.

In twenty-first embodiment, the present invention provides Venetoclax vinyl acetate.

In the first aspect of the twenty-first embodiment the crystalline form-S4 of Venetoclax vinyl acetate is characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure-5.

In twenty-second embodiment, the present invention provides a process for the preparation of crystalline form-S4 of Venetoclax vinyl acetate comprising contacting Venetoclax with vinyl acetate and to provide crystalline form-S4 of Venetoclax vinyl acetate.

In twenty-third embodiment, the present invention provides isopropyl acetate.

In first aspect of the twenty-third embodiment, the crystalline form-S5 of Venetoclax isopropyl acetate is characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure-6.

In twenty-fourth embodiment, the present invention provides a process for the preparation of Venetoclax isopropyl acetate comprising dissolving Venetoclax in isopropyl acetate and isolating to provide crystalline form-S5 of Venetoclax isopropyl acetate.

In the process of the twenty-fourth embodiment, dissolving Venetoclax in isopropyl acetate can be at a suitable temperature of about 30°C and above. Optionally, the solution can be filtered to make it particle free.

In twenty-fifth embodiment of the present invention provides Venetoclax methyl acetate. In the first aspect of the twenty-fifth embodiment, the crystalline form-S6 of Venetoclax methyl acetate is characterized by the X-ray powder diffraction (XRD) pattern as illustrated in figure-7.

In twenty-sixth embodiment, the present invention provides a process for the preparation of crystalline form-S6 of Venetoclax methyl acetate compound of formula- 1, comprising dissolving Venetoclax in methyl acetate and isolating crystalline form-S6 of Venetoclax methyl acetate.

In the process of the twenty-sixth embodiment, dissolving Venetoclax in methyl acetate can be at a suitable temperature of about 30°C and above. Optionally, the solution can be filtered to make it particle free.

In the process of the present invention, isolation of crystalline form-Sl, form-S2, form-S3, form-S4, form-S5 and form-S6 of Venetoclax can be carried out by any methods known in the art or can be isolated by employing any of the techniques, but not limited to: decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used and the like, and optionally washing with a solvent.

The starting material Venetoclax used in the present invention is obtained from any of the prior art known processes.

In an embodiment, the present invention provides Venetoclax having particle size distribution of D90 less than about 150 pm, preferably less than about 100 pm; more preferably less than about 50 pm

Venetoclax produced by the present invention can be further micronized or milled in conventional techniques to get the desired particle size to achieve desired solubility profile based on different forms of pharmaceutical composition requirements. Techniques that may be used for particle size reduction include, but not limited to ball, roller and hammer mills, and jet mills. Milling or micronization may be performed before drying, or after the completion of drying of the product.

The invention also encompasses pharmaceutical compositions comprising Venetoclax and its pharmaceutical acceptable salts of the present invention. As used herein, the term "pharmaceutical compositions" or "pharmaceutical formulations" include tablets, pills, powders, liquids, suspensions, emulsions, granules, capsules, suppositories, or injection preparations.

P-XRD Method of Analysis: PXRD analyses of compounds produced by the present invention were carried out using BRUKER/AXS X-Ray diffractometer using Cu Ka radiation of wavelength 1.5406 A°.

PSD method of Analysis: Particle size distribution (PSD) analysis was performed using Malvern Mastersizer 2000 instrument.

The process of the present invention is schematically represented as below:

Formula-4

Formula-5 Formula-6

Water, Aqu, NaOH DMSO, K₂HP0₄ Methanol, Toluene

Formula-7

Venetoclax The process described in the present invention was demonstrated in examples illustrated below. These examples are provided as illustration only and therefore should not be construed as limitation of the scope of the invention.

Examples:

Example-1: Preparation of 2-chloro-4,4-dimethylcyclohex-l-ene carbaldehyde

Phosphoryl chloride (158.0 gms) was slowly added to a pre-cooled solution of toluene (400 ml) and dimethylformamide (85.5 ml) at l0-l5°C. Raised the temperature of the reaction mixture to 20-25°C and stirred for 2 hours. 3,3-Dimethylcyclohexanone (100 gms) was slowly added to the reaction mixture at 20-25°C. Heated the reaction mixture to 50-55°C and stirred for 22 hours. Cooled the reaction mixture to 20-25°C. Reaction mixture was added to a pre-cooled aqueous solution of sodium bicarbonate, aqueous sodium chloride solution and toluene at 0-5°C. Raised the temperature of the reaction mixture to 25-30°C and stirred for 15 minutes. Both the organic and aqueous layers were separated and extracted the aqueous layer with toluene. Combined organic layers were washed with aqueous sodium bicarbonate solution and aqueous sodium chloride solution. Distilled of the organic layer under reduced pressure to get the title compound. Yield: 135.3 gms.

Example-2: Preparation of 4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2- carbaldehyde

Acetonitrile (1000 ml) was added to 2-chloro-4,4-dimethylcyclohex- 1 -ene carbaldehyde (125 gms) at 25-30°C and nitrogen gas bubbling was applied for 10 minutes. Water (500 ml), potassium carbonate (200 gms) and 4-chlorophenylboronic acid (125 gms) were added to the reaction mixture at 25-30°C and nitrogen gas bubbling was applied for 10 minutes. Tetrakistriphenyl phosphine palladium (1.25 gms) was added to the reaction mixture at 25-30°C. Heated the reaction mixture to 75-80°C and stirred for 3 hours. Cooled the reaction mixture to 25-30°C. Both the organic and aqueous layers were separated. Distilled off the solvent completely from the organic layer under reduced pressure. Toluene was added to the obtained compound at 25-30°C. Aqueous L-cysteine solution and aqueous sodium bicarbonate solution were added to the reaction mixture at 25-30°C. Activated carbon was added to the reaction mixture at 25-30°C and stirred for 20 minutes. Filtered the reaction mixture through hyflow bed and washed with toluene. Both the organic layer and aqueous layers were separated and the organic layer was washed with aqueous sodium chloride solution. Distilled off the solvent completely under reduced pressure to get the title compound.

Example-3: Preparation of tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l, l'-biphenyl]-2-yl)methyl)piperazine-l-carboxylate

THF (750 ml) and toluene (750 ml) were added to the compound obtained in example-2 at 25-30°C under nitrogen atmosphere. Tert-butyl piperazine- l-carboxylate (144.1 gms) was added to the reaction mixture at 25-30°C. Cooled the reaction mixture to l5-20°C. Sodium triacetoxyborohydride (33.44 gms) was added in six lots to the reaction mixture at l5-20°C and stirred for 4 hours. Raised the temperature of the reaction mixture to 25-30°C and stirred for 4 hours. Cooled the reaction mixture to l5-25°C. Aqueous sodium chloride solution was slowly added to the reaction mixture at l5-20°C. Raised the temperature of the reaction mixture to 25-30°C and stirred for 30 minutes. Both the organic layer and aqueous layers were separated and the aqueous layer was extracted with toluene. Both the organic layers were combined and washed with aqueous sodium bicarbonate solution. Both the organic layer and aqueous layers were separated. Distilled of the solvent from the organic later completely under reduced pressure and co-distilled with acetonitrile.

Example-4: Purification of tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l, l'-biphenyl]-2-yl)methyl)piperazine-l-carboxylate

Acetonitrile was added to the obtained compound in example-3. Heated the reaction mixture to 75-80°C and stirred for 30 minutes at the same temperature. Cooled the reaction mixture to 25-30°C and stirred for 2 hours. Cooled the reaction mixture to 0-5°C and stirred for 3 hours. Filtered the precipitated solid, washed with acetonitrile and dried to get the title compound. Yield: 241.0 gms; Impurity-I: 0.21% and Impurity-III: 0.47%.

Example-5: Purification of tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro- [l,l'-biphenyl]-2-yl)methyl)piperazine-l-carboxylate

Tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl) piperazine- l-carboxylate (3.0 gms) was dissolved in acetone (9.0 ml) at 25-30°C. Heated the reaction mixture to 55-60°C and stirred for 1 hour. Cooled the reaction mixture to 25-30°C and stirred for 3 hours. Filtered the precipitated solid, washed with acetone and dried to get the title compound. Yield: 2.6 gms; Impurity-I: 0.05% and impurity- III: 0.1%.

Example-6: preparation of l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'- biphenyl]-2-yl)methyl)piperazine

Isopropanol (600 ml) was added to tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetra hydro-[l,l'-biphenyl]-2-yl)methyl)piperazine-l-carboxylate [100 gms] at 25-30°C. Aqueous hydrochloric acid solution was slowly added to the reaction mixture at 25-30°C. Heated the reaction mixture to 75-80°C and stirred for 6 hours. Cooled the reaction mixture to 25-30°C and stirred for 2 hours. Cooled the reaction mixture to 0-5°C and stirred for 3 hours. Filtered the precipitated solid, washed with isopropanol and dried to get the title compound.

Yield: 86.0 gms; M.R: 225-228°C.

Example-7: Preparation of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate

Water (500 ml) was added to l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,F- biphenyl]-2-yl)methyl)piperazine dihydrochloride (175 gms) at 25-30°C. The pH of the reaction mixture was adjusted to 10-12 using aqueous sodium hydroxide solution. Toluene (800 ml) was added to the reaction mixture at 25-30°C and stirred for 15 minutes. Both the organic layer and aqueous layers were separated and the aqueous layer extracted with toluene. Both the organic layers were combined. Aqueous sodium chloride solution was added to the reaction mixture at 25-30°C and stirred for 30 minutes. Both the organic layer and aqueous layers were separated. Distilled off the solvent from the organic layer completely under reduced pressure. Dimethylsulf oxide (1000 ml) was added to the obtained compound under nitrogen atmosphere at 25-30°C. Methyl 2-((lH-pyrrolo[2,3-b]pyridin-5- yl)oxy)-4-fluorobenzoate (100 gms) was added to the reaction mixture under nitrogen atmosphere at 25-30°C. Di-potassium hydrogen phosphate (182.5 gms) was added to the reaction mixture at 25-30°C. Heated the reaction mixture to l25-l30°C and stirred for 26 hours. Cooled the reaction mixture to 25-30°C. Water and methyl tert-butyl ether was added to the reaction mixture at 25-30°C and stirred for 20 minutes. Both the organic layer and aqueous layers were separated and aqueous layer was extracted with methyl tert-butyl ether at 25-30°C. Combined the organic layers and washed with aqueous sodium chloride solution. Both the organic layer and aqueous layers were separated. Distilled off the solvent from the organic layer completely under reduced pressure and co-distilled with methanol to get the title compound.

Yield: 159.5 gms; Purity by HPLC: 81%.

Example-8: Purification of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate

Methanol (550 ml) and toluene (50 ml) was added to the compound obtained in example-7 at 25-30°C and stirred for 15 minutes. Heated the reaction mi ture to 50-55°C and stirred for 45 minutes. Cooled the reaction mixture to 25-30°C and stirred for 3 hours. Filtered the precipitated solid, washed with methanol and dried to get the title compound. Yield: 136 gms; M.R: l7l-l72°C; Purity by HPLC: 95%.

Example-9: Preparation of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5- dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid hydrochloride

Methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4, 5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoate (100 gms) was dissolved in dimethylsulfoxide (1000 ml) at 25-30°C. Aqueous sodium hydroxide solution was slowly added to the reaction mixture at 25-30°C and stirred for 3 hours at the same temperature. Water (300 ml) was added to the reaction mixture at 25-30°C. The pH of the reaction mixture was adjusted to 2-3 with aq. hydrochloride solution at 25-30°C. Filtered the precipitated solid, washed with water and dried to get the compound.

Yield: 100 gms; Purity by HPLC: 95%.

Example-10: Purification of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5- dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid hydrochloride

Formic acid (2.0 ml) was added to the compound obtained in example-9 at 25-30°C and stirred for 10-15 minutes at the same temperature. Isopropanol (18.0 ml) was slowly added to the reaction mixture at 25-30°C and stirred for 4 hours. Filtered the precipitated solid, washed with isopropanol and dried to get the title compound.

Yield: 90 gms; M.R: > 250°C. Purity by HPLC: 98%

Example-11: Preparation of Venetoclax

3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)benzenesulfonamide (57.09 gms), l-ethyl-3-(3-dimethylaminopropyl)carbodiimides hydrochloride (47.32 gms) and dimethylaminopyridine (40.19 gms) were added to the dichloromethane (500 ml) at 25-30°C. A mixture of dichloromethane (500 ml), triethylamine (66.56 gms) and 2-((lH-pyrrolo[2,3- b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl) methyl)piperazin-l-yl)benzoic acid hydrochloride (100 gms) were slowly added to the reaction mixture at 25-30°C and stirred for 24 hours at the same temperature. Water (500 ml) was added to the reaction mixture at 25-30°C and stirred for 15 minutes. Both the organic layer and aqueous layers were separated. Acetic acid solution was slowly added to the organic layer at 25-30°C and stirred for 15 minutes. Both the organic layer and aqueous layers were separated and organic layer washed with acetic acid solution. Methanol (100 ml), acetone (25 ml) and dichloromethane (300 ml) were added to the organic layer at 25-30°C. Organic layer washed with sodium bicarbonate solution. Distilled off the solvent completely from the organic layer under reduced pressure to get the title compound.

Example-12: Preparation of crystalline form-Nl of Venetoclax

Methyl isobutyl ketone (600 ml) and isopropanol (400 ml) were added to the obtained compound in example- 11 at 25-30°C. Raised the temperature of the reaction mixture to 75- 80°C and stirred for 30 minutes. Cooled the reaction mixture to 25-30°C and stirred for 3 hours. Filtered the precipitated solid, washed with methyl isobutyl ketone and dried to get the title compound. Yield: 120 gms.

The PXRD of the obtained compound was depicted in figure-8.

Example-13: Preparation of crystalline form-N2 of Venetoclax

Methyl isobutyl ketone (700 ml) and l,4-dioxane (100 ml) were added to the obtained compound in example- 12 at 25-30°C. Raised the temperature of the reaction mixture to 75- 80°C and stirred for 15 minutes. Silica gel and carbon was added to the reaction mixture at 75-80°C and stirred for 15 minutes. Filtered the reaction mixture through hyflow bed and washed with methyl isobutyl ketone. Cooled the reaction mixture to 25-30°C and stirred for 4 hours. Filtered the precipitated solid, washed with methyl isobutyl ketone to get the title compound. The PXRD of the obtained compound was depicted in figure-9.

Example-14: Purification of Venetoclax

Methyl isobutyl ketone (560 ml) and l,4-dioxane (80 ml) were added to the obtained wet compound in example- 13 at 25-30°C. Raised the temperature of the reaction mixture to 75-80°C and stirred for 15 minutes. Cooled the reaction mixture to 25-30°C and stirred for 4 hours. Filtered the precipitated solid, washed with methyl isobutyl ketone and dried to get the title compound. Yield: 70 gms.

Example-15: Preparation of amorphous Venetoclax

Venetoclax (100 gms) was dissolved in dimethylsulfoxide (300 ml) at 35-40°C and stirred 10-15 minutes at the same temperature. Filtered the reaction mixture to make it particle free and washed with dimethylsulfoxide (100 ml). Water (6000 ml) was added to the reaction mixture at 25-30°C and nitrogen gas bubbling was applied for 15-20 minutes at the same temperature. Raised the temperature of the reaction mixture to 45-50°C and stirred for 2-3 hours at the same temperature. Filtered the precipitated solid, washed with water and dried. Water (1000 ml) was added to the above obtained compound at 25-30°C and nitrogen gas bubbling was applied for 15-20 minutes at the same temperature. Raised the temperature of the reaction mixture to 45-50°C and stirred for 1-2 hours at the same temperature. Filtered the precipitated solid, washed with water and dried to get the title compound.

Yield: 82.0 gms; M.R: l35-l38°C; Purity by HPLC: 99.95%; Sulfonamide impurity: Not detected; Acid impurity: Not detected; Fluoro sulfonamide impurity: Not detected; Ester impurity: Not detected; Deschloro sulfonamide impurity: 0.02%; N-Oxide impurity: Not detected; Impurity-I: Not detected; Impurity-IV: 0.03%.

Particle Size Distribution (PSD): Before micronization: D(l0) is 0.50 pm; D(50) is 3.63 pm; D(90) is 22.7 pm; After micronization: D(l0) is 0.33 pm; D(50) is 1.12 pm; D(90) is 3.26 pm.

Example-15: Preparation of 3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino) benzenesulfonamide

Triethyl amine (106.90 gms) was added to a mixture of acetonitrile (500 ml) and (tetra hydro-2H-pyran-4-yl)methanamine (73.0 gms) at 25-30°C. Heated the reaction mixture to 70-75°C and stirred for 8 hours. Cooled the reaction mixture to 25-30°C and stirred for 2 hours. Cooled the reaction mixture to 0-5°C and stirred for 2 hours. Filtered the solid and washed with acetonitrile. Water (1000 ml) was added to the obtained compound at 25-30°C. Heated the reaction mixture to 40-45°C and stirred for 2 hours. Filtered the solid, washed with water and dried to get the title compound. Yield: 120 gms; M.R: l89-l9l°C.

Example-16: Preparation of crystalline form-M of Venetoclax

Venetoclax (2.0 gms) was dissolved in polyethylene glycol-400 (16 ml) at 25-30°C. Heated the reaction mixture to 60-65 °C and stirred for 1 hour at the same temperature. Isobutyl acetate (16 ml) was added to the reaction mixture at 60-65 °C and stirred for 1 ½ hour at the same temperature. Filtered the precipitated solid at the same temperature and dried to get the title compound. Yield: 1.0 gms.

The PXRD pattern of the obtained compound is depicted in Figure- 1.

Example-17: Preparation of crystalline form-M of Venetoclax

Venetoclax (1.0 gms) was dissolved in polyethylene glycol-400 (11 ml) at 25-30°C and stirred for 15 minutes at the same temperature. Slowly heated the reaction mixture to 60- 65 °C and stirred for 1 hour at the same temperature. Water (50 ml) was added to the reaction mixture at 60-65 °C and stirred for 15 minutes at the same temperature. Filtered the solid and dried to get the title compound. Yield: 0.9 gms.

The PXRD pattern of the obtained compound is depicted in Figure- 1.

Example-18: Preparation of crystalline form-M of Venetoclax

Polyethylene glycol-400 (10 ml) was added to Venetoclax (500 mg) at 25-30°C. Heated the reaction mixture to 60-65 °C and stirred for 1 ½ hours at the same temperature. Filtered the solid and dried to get the title compound. Yield: 400 mg.

The PXRD pattern of the obtained compound is depicted in Figure- 1.

Example-19: Preparation of crystalline form-M of Venetoclax

Water (20 ml) was added to Venetoclax (500 mg) obtained in example-3 at 25-30°C. Heated the reaction mixture to 60-65 °C and stirred for 2 ½ hours at the same temperature. Filtered the solid and dried to get the title compound. Yield: 400 mg.

The PXRD pattern of the obtained compound is depicted in Figure- 1. Example-20: Preparation of crystalline form-M of Venetoclax

Isobutyl acetate (20 ml) was added to Venetoclax (1.0 gms) at 25-30°C and stirred for 1 hour at the same temperature. Filtered the solid and dried to get the title compound.

Yield: 800 mg. The PXRD pattern of the obtained compound is depicted in Figure- 1.

Example-21: Preparation of crystalline form-Sl of Venetoclax tetrahydrofuran.

Tetrahydrofuran (50 ml) was added to Venetoclax (5.0 gms) at 25-30°C and stirred for 15 minutes at the same temperature. The reaction mixture was added to pre -heated water (100 ml) at 60-65 °C and stirred for 1 hour at the same temperature. Filtered the precipitated solid and washed with water. To the obtained wet compound, water (5.0 ml) was added at 25-30°C. Heated the reaction mixture to 60-65°C and stirred form 1 hour at the same temperature. Filtered the solid and dried to get the title compound.

Yield: 4.2 gms. The PXRD pattern of the obtained compound is depicted in Figure-2.

Example-22: Preparation of crystalline form-S2 of Venetoclax xylene.

Xylene (55 ml) was added to Venetoclax (2.0 gms) at 25-30°C and stirred form 10 minutes at same temperature. Heated the reaction mixture to 60-65°C and stirred for 1 hour at the same temperature. Filtered the precipitated solid and dried to get the title compound. Yield: 1.5 gms. The PXRD pattern of the obtained compound is depicted in Figure-3.

Example-23: Preparation of crystalline form-S3 of Venetoclax nitro methane.

Nitro methane (500 ml) was added Venetoclax (5.0 gms) at 25-30°C and stirred for 20 minutes at same temperature. Slowly heated the reaction mixture to 65°C and stirred for 1 hour at the same temperature. Slowly cooled the reaction mixture to 25-30°C and stirred for 1 hour at same temperature. Filtered the precipitated solid and dried to get the title compound. Yield: 4.2 gms. The PXRD pattern of the obtained compound is depicted in Figure-4.

Example-24: Preparation of crystalline form-S4 of Venetoclax vinyl acetate.

Vinyl acetate (10 ml) was added to Venetoclax (500 mg) at 25-30°C and stirred for 15 minutes at the same temperature. Heated the reaction mixture to 60-65 °C and stirred for 2 hour at the same temperature. Filtered the precipitated solid and dried to get the title compound. Yield: 300 mg.

The PXRD pattern of the obtained compound is depicted in Figure-5.

Example-25: Preparation of crystalline form-S5 of Venetoclax isopropyl acetate. Isopropyl acetate (50 ml) was added to Venetoclax (0.5 gms) at 25-30°C and stirred for 15 minutes at the same temperature. Slowly heated the reaction mixture to 60-65°C and stirred for 2 hours at the same temperature. Filtered the precipitated solid and dried to get the title compound. Yield: 350 mg.

The PXRD pattern of the obtained compound is depicted in Figure-6.

Example-26: Preparation of crystalline form-S6 of Venetoclax methyl acetate.

Methyl acetate (55 ml) was added to Venetoclax (0.5 gms) at 25-30°C and stirred for 15 minutes at the same temperature. Slowly heated the reaction mixture to 60-65°C and stirred for 2 hour at the same temperature. Filtered the precipitated solid and dried to get the title compound. Yield: 380 mg.

The PXRD pattern of the obtained compound is depicted in Figure-7.

Example-27: Preparation of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate

Water (150 Lt) was added to l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,F- biphenyl]-2-yl)methyl)piperazine dihydrochloride (52.50 Kg) at 25-30°C and stirred for 10 minutes. The pH of the reaction mixture was adjusted to 10-12 using aqueous sodium hydroxide solution. Toluene (240 Lt) was added to the reaction mixture at 25-30°C and stirred for 15 minutes. Both the organic layer and aqueous layers were separated and the aqueous layer extracted with toluene. Both the organic layers were combined. Aqueous sodium chloride solution was added to the reaction mixture at 25-30°C and stirred for 30 minutes. Both the organic layer and aqueous layers were separated. Distilled off the solvent from the organic layer completely under reduced pressure. Dimethylsulfoxide (300 Lt) was added to the obtained compound under nitrogen atmosphere at 25-30°C. Methyl 2-((lH- pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-fluorobenzoate (30 Kg) was added to the reaction mixture under nitrogen atmosphere at 25-30°C. Di-potassium hydrogen phosphate (54.60 Kg) was added to the reaction mixture at 25-30°C. Heated the reaction mixture to l25-l30°C and stirred for 26 hours. Cooled the reaction mixture to 25-30°C. Water and methyl tert-butyl ether was added to the reaction mixture at 25-30°C and stirred for 20 minutes. Both the organic layer and aqueous layers were separated and aqueous layer was extracted with methyl tert-butyl ether at 25-30°C. Combined the organic layers and washed with aqueous sodium chloride solution. Both the organic layer and aqueous layers were separated. Distilled off the solvent from the organic layer completely under reduced pressure and co-distilled with methanol to get the title compound.

Example-28: Purification of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate

Methanol (165 Lt) and toluene (15 Lt) was added to the compound obtained in example-7 at 25-30°C and stirred for 15 minutes. Heated the reaction mixture to 50-55°C and stirred for 45 minutes. Cooled the reaction mixture to 25-30°C and stirred for 3 hours. Filtered the precipitated solid, washed with methanol and dried to get the title compound. Yield: 44.76 Kg; M.R: l7l-l72°C; Purity by HPLC: 96%.

Example-29: Preparation of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5- dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid hydrochloride

Methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4, 5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoate (38.0 Kg) was dissolved in dimethylsulfoxide (380 Lt) at 25-30°C and stirred for 15 minutes. Aqueous sodium hydroxide solution was slowly added to the reaction mixture at 25-30°C and stirred for 3 hours at the same temperature. Water (114 Lt) was added to the reaction mixture at 25-30°C. The pH of the reaction mixture was adjusted to 2-3 with aq. hydrochloride solution at 25- 30°C. Filtered the precipitated solid, washed with water and dried to get the title compound. Example-30: Purification of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5- dimethyl-3,4,5,6-tetrahydro-[l,l'-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid hydrochloride

Formic acid (76 Lt) was added to the compound obtained in example-29 at 25-30°C and stirred for 10-15 minutes at the same temperature. Isopropanol (684 Lt) was slowly added to the reaction mixture at 25-30°C and stirred for 4 hours. Filtered the precipitated solid, washed with isopropanol and dried to get the title compound.

Yield: 37.49 Kg; M.R: > 250°C. Purity by HPLC: 98.5% Example-31: Preparation of Venetoclax

3-nitro-4-(((tetrahydro-2H-pyran-4-yl)methyl)amino)benzenesulfonamide compound of formula-lO (14.25 Kg), l-ethyl-3-(3-dimethylaminopropyl)carbodiimides hydrochloride (11.75 Kg) and dimethylaminopyridine (10 Kg) were added to the dichloromethane (125 Lt) at 25-30°C. A mixture of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5, 5- dimethyl-3 ,4,5 , 6-tetrahydro- [1,1 '-biphenyl] -2-yl)methyl)piperazin- 1 -yl)benzoic acid hydrochloride (25 Kg), dichloromethane (125 Lt) and triethylamine (16.75 Kg) were slowly added to the reaction mixture at 25-30°C and stirred for 24 hours at the same temperature. Water (125 Lt) was added to the reaction mixture at 25-30°C and stirred for 15 minutes. Both the organic layer and aqueous layers were separated. Acetic acid solution was slowly added to the organic layer at 25-30°C and stirred for 15 minutes. Both the organic layer and aqueous layers were separated and organic layer washed with acetic acid solution. Methanol (25 Lt), acetone (7 Lt) and dichloromethane (75 Lt) were added to the organic layer at 25-30°C. Organic layer washed with sodium bicarbonate solution. Distilled off the solvent completely from the organic layer under reduced pressure to get the title compound.

Example-32: Preparation of crystalline form-Nl of Venetoclax

Methyl isobutyl ketone (150 Lt) and isopropanol (100 Lt) were added to the obtained compound in example-l l at 25-30°C. Raised the temperature of the reaction mixture to 75- 80°C and stirred for 30 minutes. Cooled the reaction mixture to 25-30°C and stirred for 3 hours. Filtered the precipitated solid, washed with methyl isobutyl ketone and dried to get the title compound. The PXRD of the obtained compound was depicted in figure-8.

Example-33: Preparation of crystalline form-N2 of Venetoclax

Methyl isobutyl ketone (175 Lt) and l,4-dioxane (25 Lt) were added to the obtained compound in example-l2 at 25-30°C. Raised the temperature of the reaction mixture to 75- 80°C and stirred for 15 minutes. Silica gel and carbon was added to the reaction mixture at 75-80°C and stirred for 15 minutes. Filtered the reaction mixture through hyflow bed and washed with methyl isobutyl ketone. Cooled the reaction mixture to 25-30°C and stirred for 4 hours. Filtered the precipitated solid, washed with methyl isobutyl ketone to get the title compound. The PXRD of the obtained compound was depicted in figure-9. Example-34: Purification of Venetoclax

Methyl isobutyl ketone (140 Lt) and l,4-dioxane (20 Lt) were added to the obtained wet compound in example- 13 at 25-30°C. Raised the temperature of the reaction mixture to 75-80°C and stirred for 15 minutes. Cooled the reaction mixture to 25-30°C and stirred for 4 hours. Filtered the precipitated solid, washed with methyl isobutyl ketone and dried to get the title compound. Yield: 19.29 Kg.

Example-35: Preparation of amorphous Venetoclax

Venetoclax (18 Kg) was dissolved in dimethylsulfoxide (49 Lt) at 35-40°C and stirred 10-15 minutes at the same temperature. Filtered the reaction mixture to make it particle free and washed with dimethylsulfoxide (5 Lt). Water (1080 Lt) was added to the reaction mixture at 25-30°C and nitrogen gas bubbling was applied for 15-20 minutes at the same temperature. Raised the temperature of the reaction mixture to 45-50°C and stirred for 2-3 hours at the same temperature. Filtered the precipitated solid, washed with water and dried. Water (180 Lt) was added to the above obtained compound at 25-30°C and nitrogen gas bubbling was applied for 15-20 minutes at the same temperature. Raised the temperature of the reaction mixture to 45-50°C and stirred for 2 hours at the same temperature. Filtered the precipitated solid, washed with water and dried to get the title compound.

Yield: 15.46 Kg; M.R: l35-l38°C; Purity by HPLC: 99.96%; Sulfonamide impurity: Not detected; Acid impurity: Not detected; Fluoro sulfonamide impurity: Not detected; Ester impurity: Not detected; Deschloro sulfonamide impurity: 0.02%; N-Oxide impurity: Not detected; Impurity-I: Not detected; Impurity-IV: 0.03%.

Particle Size Distribution (PSD): Before micronization: D(l0) is 1.37 pm; D(50) is 9.53 pm; D(90) is 30.59 pm; After micronization: D(l0) is 0.33 pm; D(50) is 1.12 pm; D(90) is 3.26 pm.

Claims

We Claim:

1. A process for the preparation of substantially pure Venetoclax compound of formula- 1,

comprising:

a) Purifying tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2- yl)methyl)piperazine-l-carboxylate of compound of formula-5 from a solvent, b) converting the pure compound of formula-5 to Venetoclax.

2. The process as claimed in claim 1 wherein solvent used in step-a) is selected from ketone solvents, nitrile solvents or mixture thereof.

3. The process as claimed in claim 1 wherein Venetoclax is free of impurity-I, impurity-II, impurity- III and impurity-IV.

4. The process as claimed in claim 1 wherein a process for the preparation of tert-butyl 4- ((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2-yl)methyl)piperazine-l- carboxylate compound of formula-5, comprising: a) reacting 3,3-dimethylcyclohexanone compound of formula-2 with phosphoryl chloride and dimethylformamide to provide 2-chloro-4,4-dimethylcyclohex-l-ene carbaldehyde compound of formula-3,

b) reacting the compound of formula-3 with 4-chlorophenyl boronic acid or its esters in the presence of palladium catalyst at a temperature ranging from 30-l20°C to provide compound of formula-4,

c) reacting the compound of formula-4 with tert-butyl piperazine- 1 -carboxylate in the presence of sodium triacetoxyborohydride in tetrahydrofuran and toluene to provide tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl) piperazine- 1 -carboxylate compound of formula-5.

5. The process as claimed in claim 4 wherein, a process for the preparation of Venetoclax comprising converting compound of formula-5 to Venetoclax, comprising the following steps:

a) treating tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2-yl) methyl )piperazine- 1 -carboxylate compound of formula-5 with hydrochloric acid source to provide l-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2-yl) methyl)piperazine hydrochloride compound of formula-6,

b) treating the compound of formula-6 with a base to provide l-((4'-chloro-5,5-dimethyl- 3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazine compound of formula-IV, c) reacting the compound of formula-IV with methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl) oxy)-4-fluorobenzoate compound of formula-7 in the presence of dipotassium hydrogen phosphate to provide 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate compound of formula- 8,

d) optionally purifying compound of formula-8 with a solvent to provide pure compound of formula-8,

e) treating the compound of formula-8 with a base to provide 2-((lH-pyrrolo[2,3-b] pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2- yl)methyl)piperazin- 1 -yl)benzoic acid compound of formula-V followed by treating it with hydrochloric acid source to provide 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4- (4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazin- l-yl)benzoic acid hydrochloride compound of formula-9,

f) reacting the compound of formula-9 with 3-nitro-4-(((tetrahydro-2H-pyran-4-yl) methyl)amino)benzenesulfonamide compound of formula-III in presence of coupling agent and a base in a solvent to provide Venetoclax compound of formula- 1, g) optionally purifying Venetoclax using a solvent to provide pure Venetoclax compound of formula- 1.

6. The process as claimed in claim 5 step-g) wherein a process for the purification of Venetoclax comprising dissolving in a solvent selected from alcohol solvents, ketone solvents, ether solvents, ketone solvents or mixture thereof and isolating Venetoclax.

7. A process for the preparation of Venetoclax, comprising:

a) reacting 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 with 4-chlorophenyl boronic acid or its esters in the presence of palladium catalyst at a temperature ranging from 30°C to l20°C to provide 4'-chloro-5,5-dimethyl-3, 4,5,6- tetrahydro-[l,l'-biphenyl]-2-carbaldehyde compound of formula-4,

b) converting compound of formula-4 to Venetoclax.

8. The process as claimed in claim 7 wherein, the palladium catalyst used is selected from 1 , 1 '-bis(diphenylphosphino)ferrocene]dichloropalladium(II)(Pd(dppf)Cl2), tetrakis(tri phenylphosphine) palladium (0) (Pd(PPh₃)4), palladium (Il)chloride (PdCl₂), bis (benzonitrile)palladium(II)dichloride (Pd(PhCN)2Cl2), bis(triphenylphosphine)palladium (II) dichloride (Pd(PPh3)2Cl2), and allyl palladium (II) chloride dimer (PdCKCsHs)^). The suitable base is selected from organic or inorganic base. The suitable solvent is selected from alcohol solvents, nitrile solvents, ester solvents, chloro solvents, ketone solvents, ether solvents, water or mixture thereof.

9. A process for the preparation of 2-chloro-4,4-dimethylcyclohex- 1 -enecarbaldehyde compound of formula-3 comprising reacting compound of formula-2 with phosphoryl chloride and dimethylformamide in the presence of organic solvent.

10. The process as claimed in claim 9 wherein, the organic solvent is selected from alcohol solvents, nitrile solvents, ester solvents, hydrocarbon solvents, chloro solvents, ketone solvents, ether solvents, water or mixture thereof;

11. The process as claimed in claim 9 wherein, the organic solvent is hydrocarbon solvent.

12. A process for the purification of methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazin-l-yl) benzoate compound of formula-8 comprising dissolving / suspending compound of formula-8 in a solvent and isolating pure compound of formula-8.

13. The process as claimed in claim 12 wherein, dissolving compound of formula-8 in a solvent selected from alcohol solvents, hydrocarbon solvents and water or mixtures.

14. The process as claimed in claim 12 wherein, dissolving compound of formula-8 at a suitable temperature ranging from 30°C and above to provide a solution of compound of formula- 8.

15. The process as claimed in claim 12, wherein, isolating the pure compound of formula-8 by employing any of the techniques such as cooling, decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration, or other techniques specific to the equipment used, and optionally washing with a solvent

16. The process as claimed in claim 12 wherein the compound of formula-8 is useful in the preparation of pure Venetoclax.

17. A process for the purification of 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro- 5,5-dimethyl-3,4,5,6-tetrahydro-[l, r-biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid compound of formula-9 comprising:

a) dissolving compound of formula-9 in a solvent,

b) adding an anti-solvent to the solution obtained in step-a), and

c) isolating the pure compound of formula-9.

18. The process as claimed in claim 17 wherein, dissolving compound of formula-9 in a solvent selected from selected from nitrile solvents, ester solvents, hydrocarbon solvents, polar aprotic solvents, chloro solvents, ketone solvents, ether solvents, water, acetic acid, formic acid or mixture thereof.

19. The process as claimed in claim 17 step-b) wherein anti-solvent is alcohol solvents; preferably isopropanol.

20. The process as claimed in claim 17 wherein the compound of formula-9 is useful in the preparation of pure Venetoclax.

21. A process for the preparation of Venetoclax which is free of impurities hereinafter referred to as Impurity-I, Impurity- II, Impurity- III and Impurity- IV, comprising:

a) Reacting 2-chloro-4,4-dimethylcyclohex-l-enecarbaldehyde compound of formula-3 with 4-chlorophenyl boronic acid or its esters in the presence of palladium catalyst and a base at a temperature ranging from 30-l20°C to provide compound of formula-4, b) reacting the compound of formula-4 with tert-butyl piperazine- 1 -carboxylate in the presence of sodium triacetoxyborohydride in tetrahydrofuran and toluene to provide tert-butyl 4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,T-biphenyl]-2-yl)methyl) piperazine- 1 -carboxylate compound of formula-5,

c) optionally purifying the compound of formula-5 using a solvent, d) treating the compound of formula-5 with hydrochloric acid source to provide l-((4'- chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazine hydrochloride compound of formula-6,

e) treating the compound of formula-6 with a base to provide l-((4'-chloro-5,5-dimethyl- 3,4,5,6-tetrahydro-[l,r-biphenyl]-2-yl)methyl)piperazine compound of formula-IV, f) reacting the compound of formula-IV with methyl 2-((lH-pyrrolo[2,3-b]pyridin-5-yl) oxy)-4-fluorobenzoate compound of formula-7 in the presence of dipotassium hydrogen phosphate in a solvent to provide 2-((lH-pyrrolo[2,3-b]pyridin-5-yl)oxy)-4- (4-((4'-chloro-5 ,5 -dimethyl-3 ,4,5 ,6-tetrahydro- [ 1 , 1 '-biphenyl] -2-yl)methyl)piperazin- 1 - yl)benzoate compound of formula-8,

h) treating the compound of formula-8 with a base in a solvent to provide 2-((lH- pyrrolo[2,3-b]pyridin-5-yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r- biphenyl]-2-yl)methyl)piperazin-l-yl)benzoic acid compound of formula- V followed by treating it with hydrochloric acid source to provide 2-((lH-pyrrolo[2,3-b]pyridin-5- yl)oxy)-4-(4-((4'-chloro-5,5-dimethyl-3,4,5,6-tetrahydro-[l,r-biphenyl]-2- yl)methyl)piperazin-l-yl) benzoic acid hydrochloride compound of formula-9, i) reacting the compound of formula-9 with 3-nitro-4-(((tetrahydro-2H-pyran-4- yl)methyl)amino)benzenesulfonamide compound of formula-III in the presence of coupling agent in a base in a solvent to provide Venetoclax compound of formula- 1, j) optionally purifying Venetoclax using a solvent to provide pure Venetoclax compound of formula- 1.

22. Crystalline form-Nl of Venetoclax which is characterized by its PXRD pattern as depicted in figure-8.

23. A process for the preparation of crystalline form-Nl of Venetoclax comprises dissolving

Venetoclax in a solvent to provide a solution of Venetoclax and isolating crystalline form-

Nl of Venetoclax.

24. The process as claimed in claim 23 wherein, the solvent is selected from alcohol solvents, ketone solvents or mixtures thereof.

25. The process as claimed in claim 23 wherein, isolating crystalline form-Nl of Venetoclax by employing any of the techniques such as cooling, decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration and optionally washing with a solvent to provide crystalline form-Nl of Venetoclax.

26. Crystalline form-N2 of Venetoclax which is characterized by its PXRD pattern as depicted in figure-9.

27. A process for the preparation of crystalline form-N2 of Venetoclax comprising dissolving Venetoclax in a solvent to provide a solution of Venetoclax and isolating crystalline form- N2 of Venetoclax.

28. The process as claimed in claim 27 wherein, the solvent selected from ether solvents, ketone solvents or mixtures thereof.

29. Venetoclax obtained according to the preceding claims having a purity of greater than about 99.9%; preferably greater than about 99.95%; more preferably greater than about 99.99% as measure by HPLC.

30. Substantially pure Venetoclax compound of formula- 1 is free of impurity-I, Impurity-II, Impurity-III and Impurity-IV.

31. Substantially pure Venetoclax compound of formula- 1 Sulfonamide impurity; Acid impurity; Fluoro sulfonamide impurity; Ester impurity; Deschloro sulfonamide impurity; N-Oxide impurity; and Dimer impurity less than 0.05% as measured by HPLC.

32. The process according to the preceding claims, wherein Venetoclax having particle size distribution of D90 less than about 150 pm, preferably less than about 100 pm; more preferably less than about 50 pm.

33. Venetoclax having particle size distribution of D90 less than about 10 pm.

34. Venetoclax obtained according to preceding claims is useful for the preparation of pharmaceutical composition.

35. A pharmaceutical composition comprising Venetoclax according to preceding claims and a pharmaceutically acceptable carrier or diluent.

36. Crystalline form-M of Venetoclax characterized by its X-ray powder diffraction (XRD) pattern having peaks at about 4.6, 6.9, 8.7, 10.3, 10.9, 13.9, 18.7 and 21.1 ± 0.2 degrees of 2-theta.

37. A process for the preparation of crystalline form-M of Venetoclax, comprising contacting Venetoclax with an organic solvent selected from alcohol solvents, ester solvents and water or mixtures thereof and isolating crystalline form-M of Venetoclax.

38. A process for the preparation of crystalline form-M of Venetoclax comprising:

a) Dissolving / suspending Venetoclax in alcohol solvent,

b) adding anti-solvent to a solution containing Venetoclax or vice-versa,

c) isolating crystalline form-M of Venetoclax.

39. The process as claimed in claim 38 wherein, anti-solvent used in step-b) is selected from ester solvents or water; and isolating crystalline form-M of Venetoclax by employing any of the techniques such as decantation, filtration by gravity or suction, centrifugation.

40. Crystalline forms of Venetoclax: a) Crystalline form-Sl of Venetoclax tetrahydrofuran is characterized by the X-ray powder diffraction (XRD) pattern as depicted in figure-2.

b) Crystalline form-S2 of Venetoclax xylene is characterized by the X-ray powder diffraction (XRD) pattern as depicted in figure-3.

c) Crystalline form-S3 of Venetoclax nitro methane is characterized by the X-ray powder diffraction (XRD) pattern as depicted in figure-4.

d) Crystalline form-S4 of Venetoclax vinyl acetate is characterized by the X-ray powder diffraction (XRD) pattern as depicted in figure-5.

e) Crystalline form-S5 of Venetoclax isopropyl acetate is characterized by the X-ray powder diffraction (XRD) pattern as depicted in figure-6.

f) Crystalline form-S6 of Venetoclax methyl acetate is characterized by the X-ray powder diffraction (XRD) pattern as depicted in figure-7.

41. A process for the preparation of crystalline forms of Venetoclax

a) A process for the preparation of crystalline form-Sl of Venetoclax tetrahydrofuran compound of formula- 1, comprising dissolving Venetoclax in tetrahydrofuran and adding a solution of Venetoclax in tetrahydrofuran to a pre-heated water and isolating crystalline form-Sl of Venetoclax tetrahydrofuran.

b) A process for the preparation of crystalline form-S2 of Venetoclax xylene comprising dissolving Venetoclax in xylene and isolating crystalline form-S2 of Venetoclax xylene. c) A process for the preparation of crystalline form-S3 of Venetoclax nitro methane comprising dissolving Venetoclax in nitromethane and isolating crystalline form-S3 of Venetoclax nitro methane.

d) A process for the preparation of crystalline form-S4 of Venetoclax vinyl acetate comprising contacting Venetoclax with vinyl acetate and to provide crystalline form-S4 of Venetoclax vinyl acetate.

e) A process for the preparation of crystalline form-S6 of Venetoclax methyl acetate compound of formula- 1, comprising dissolving Venetoclax in methyl acetate and isolating crystalline form-S6 of Venetoclax methyl acetate.

42. The process as claimed in claim 41 wherein isolating crystalline form-Sl, form-S2, form- 83, form-S4, form-S5 and form-S6 of Venetoclax by employing any of the techniques such as decantation, filtration by gravity or suction, centrifugation, adding solvent to make slurry followed by filtration.

43. Compounds having structural formulae:

44. Substantially pure compound of formula-5 containing the following compounds less than

0.05%. Boc