Green synthesis method of 3, 4-disubstituted isoquinoline derivative promoted by room-temperature illumination
Technical Field
The invention belongs to the technical field of organic synthetic chemistry, and relates to a green synthesis method of a 3, 4-disubstituted isoquinoline derivative promoted by room-temperature illumination.
Background
Isoquinoline and derivatives thereof are important N-heterocyclic compounds, and are a very important class of medicines, natural products, active biomolecules and the like. The research on the synthetic method is highly valued by the academic and industrial circles at home and abroad [ see: (a) g, O' Donnell, R. Poeschl, O. Zimhony, M. Gunaratnam, J.B.C. Moreira, S.Neidle, D. Evangelopoulos, S. Bhakta, J.P. Malkinson, H.I. Boshoff, A.Lenaerts and S. Gibbons,J. Nat. Prod., 2009,72, 360;(b) J. A. Bull, J. J.Mousseau, G. Pelletier and A. B. Charette,Chem. Rev., 2012,112, 2642.]. At present, the transition metal catalyzed C-H coupling reaction is an excellent method for synthesizing isoquinoline in organic chemistry due to its stepwise high efficiency and atom economy [ see: (a) r, He, Z.T. Huang, Q.Y. Zheng and C. Wang,Angew. Chem., Int. Ed., 2014,53, 4950;(b) D. Zhao, F. Lied and F. Glorius,Chem. Sci., 2014,5, 2869;(c) X. L. Wu and L. Dong,Org. Lett., 2018,20, 6990.]. However, most of these studies have so far focused on the search for novel catalysts or the development of distinctive substrates. However, studies on the environmental friendliness of the reaction, such as avoiding the use or recycling of a catalyst, avoiding the use of an oxidizing agent, avoiding the use of an organic solvent, and the like, have been rarely reported. In current chemical synthesis, chemists are increasingly concerned about the development of environmental protection and sustainable technologies. Therefore, the development of a green, simple and efficient isoquinoline synthesis strategy is urgently needed. Methods for green synthesis of isoquinoline that have been reported so far include: (1) the Li topic group reports a novel cobalt catalyst and its use in the photoreaction synthesis of isoquinoline derivatives [ see: W.F. Tian, D.P. Wang, S.F. Wang, K.H. He, X.P. Caoand Y. Li,Org. Lett., 2018,20, 1421.]the Sundararaju subject group successfully synthesizes isoquinolone derivatives under photoreaction by cobalt catalysis [ see: D. kalsi, S. Dutta, N. Barsu, M. Rueping and dB. Sundararaju,ACS Catal., 2018,8, 8115.](3) Kotora topic group developed a method for synthesizing benzisoquinoline derivatives under microwave conditions [ see: D.Frejka, J. Ulč, E. A. B. Kantchev, I. Císařová and M. Kotora,ACS Catal., 2018,8, 10290.]the Bhanage group synthesizes isoquinoline derivatives and isoquinolinone derivatives using polyethylene glycol as a solvent under microwave conditions, and realizes the recycling of the ruthenium catalyst [ see: D.S. Deshmukh, N. Gangwar and B.M. Bhanage,Eur. J. Org. Chem., 2019,2919.]. However, there is still a need to develop a safe, simple, efficient, low-cost, and environmentally friendly coupling reaction to construct isoquinoline derivatives.
Disclosure of Invention
Aiming at the problems in the prior art, the invention aims to provide an efficient, mild and environment-friendly green synthesis method of a 3, 4-disubstituted isoquinoline derivative. The green synthesis method of the 3, 4-disubstituted isoquinoline derivative promoted by room temperature illumination comprises the steps of taking water and polyethylene glycol 400 as a mixed solvent, taking phenyl oxime compounds and non-terminal alkyne as raw materials, and carrying out transition metal catalyzed C-H coupling reaction at room temperature under illumination to synthesize the 3, 4-disubstituted isoquinoline derivative. The invention solves the problems of long steps, harsh reaction conditions, low atom utilization rate, toxic organic solvent use, environmental pollution, high cost and the like in the traditional isoquinoline derivative synthesis, provides a preparation method which is milder, more effective and more environment-friendly than the existing reports, and the byproduct is only water, thereby greatly improving the atom utilization rate and having good application prospect.
The technical route of the invention takes phenyl oxime compound and non-terminal alkyne as raw materials, and the phenyl oxime compound and the non-terminal alkyne are directly coupled in one step under the conditions of illumination and room temperature. The chemical reaction formula is shown as follows:
R1is one of hydrogen, halogen, alkyl, phenyl, alkoxy, carbonyl, aldehyde group, carboxyl, cyano, alkanoyloxy and amide; r2Is one of hydrogen, alkyl, phenyl and alkoxy; r3、R4Of alkyl, benzyl, phenyl, substituted aryl, heteroarylOne or two.
The green synthesis method of the 3, 4-disubstituted isoquinoline derivative is characterized by comprising the following preparation steps: adding a phenyl oxime compound, a non-terminal alkyne compound, a catalyst and water/polyethylene glycol 400 (1: 1) into a clean quartz reactor, and stirring for 24 hours at room temperature in a photochemical reactor; after completion of the reaction, saturated brine and ethyl acetate were added to conduct extraction. And distilling the ethyl acetate layer under reduced pressure to remove the solvent, and separating and purifying the residue by silica gel column chromatography to obtain the product.
Wherein the catalyst is rhodium acetate, acetylacetonatocarbonyltriphenylphosphine rhodium, dicyclooctenylrhodium chloride dimer, pentamethylcyclopentadienylrhodium acetate, dichloro (pentamethylcyclopentadienyl) rhodium dimer, ruthenium trichloride, triphenylphosphine ruthenium chloride, dichlorobis-triphenylphosphine ruthenium, bis (2-methylallyl) (1, 5-cyclooctadiene) ruthenium, one or more of p-cymene ruthenium dichloride dimer, cobalt acetoacetoxide, dichloro (pentamethylcyclopentadienyl) cobalt dimer, pentamethylcyclopentadienyl cobalt carbonyl diiodide, bis (hexafluoroantimonic acid) triethylenenitrile (pentamethylcyclopentadienyl) cobalt, iridium trichloride, dichloro (pentamethylcyclopentadienyl) iridium dimer, bis (1, 5-cyclooctadiene) iridium chloride dimer and methoxy (cyclooctadiene) iridium dimer.
Wherein, the illumination condition is a photochemical reaction instrument which takes one or more than one of a high-pressure mercury lamp, a xenon lamp, a metal halide lamp and a light-emitting diode (LED) lamp as a light generating device.
Wherein the mixing ratio of the water and the polyethylene glycol 400 as the mixed solvent is 1: 1.
Compared with the traditional reaction conditions, the invention is a green method for synthesizing the 3, 4-disubstituted isoquinoline derivative by taking water and polyethylene glycol 400 as a mixed solvent, a phenyl oxime compound and non-terminal alkyne as raw materials and carrying out a transition metal catalyzed C-H coupling reaction at room temperature under illumination, has a plurality of unique advantages and is embodied as follows:
1. the C-H coupling reaction is carried out at room temperature, and isoquinoline derivatives can be simply, conveniently and efficiently obtained;
2. the C-H coupling reaction takes water and polyethylene glycol as green solvents, and compared with the traditional organic solvent, the C-H coupling reaction has the advantages of low toxicity, incombustibility, good thermal stability and chemical stability, no generation of vapor pressure, excellent solubility and the like, and improves the reaction safety;
3. the synthetic route of the invention uses phenyl oxime compounds as raw materials, the reagent has higher safety and stability, and the byproduct generated in the reaction process is only water, thereby avoiding generating a large amount of waste and having higher atom economy and environmental friendliness.
Detailed description of the invention
The present invention will be further described with reference to specific embodiments to assist in understanding the invention. It is not intended that the scope of the invention be limited thereby, but rather that the invention be defined by the claims appended hereto.
Example 1: synthesis of 1-methyl-3, 4-diphenylisoquinoline
Acetophenone oxime (27.0 mg, 0.20 mmol), tolane (42.7 mg, 0.24 mmol), pentamethylcyclopentadienyl rhodium (II) acetate (6.7 mg, 0.01 mmol), water (0.5 mL), polyethylene glycol 400 (0.5 mL), and a high-pressure mercury lamp as a light generator were sequentially added to a clean quartz reactor and stirred at room temperature for 24 hours in a photochemical reactor. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 51.3 mg as a white solid in a yield of 87%. Melting point: 155-156oC;1H NMR (400 MHz, Chloroform-d) δ 8.23 – 8.18(m, 1H), 7.69 – 7.63 (m, 1H), 7.62 – 7.57 (m, 2H), 7.40 – 7.30 (m, 5H), 7.24– 7.15 (m, 5H), 3.08 (s, 3H).13C NMR (100 MHz, Chloroform-d) δ 157.7, 149.4,140.9, 137.5, 136.0, 131.4, 130.3, 129.9, 129.2, 128.2, 127.6, 127.1, 126.9,126.5, 126.2, 126.1, 125.5, 22.7. HRMS (ESI):m/zcalculated for C22H17NH+:296.1434, found: 296.1432。
Example 2: 1, 6-dimethyl-3, 4-diphenylisoquinoline
4-methyl acetophenone oxime (33.0 mg, 0.20 mmol), tolane (42.7 mg, 0.24 mmol), acetic acid (pentamethylcyclopentadienyl) rhodium (II) (6.7 mg, 0.01 mmol), water (0.5 mL), polyethylene glycol 400 (0.5 mL), and a high-pressure mercury lamp as a light generator were sequentially added to a clean quartz reactor and stirred at room temperature in a photochemical reactor for 24 hours. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 54.8 mg as a white solid in a yield of 89%. Melting point: 159-160oC;1H NMR (400 MHz, Chloroform-d) δ 8.08(d,J= 8.9 Hz, 1H), 7.42 – 7.38 (m, 2H), 7.37 – 7.29 (m, 5H), 7.23 – 7.13(m, 5H), 3.04 (d,J= 1.5 Hz, 3H), 2.42 (s, 3H).13C NMR (100 MHz, Chloroform-d) δ 157.4, 149.6, 141.2, 140.2, 137.8, 136.2, 131.5, 128.8, 128.7, 128.2,127.6, 127.0, 126.8, 125.5, 125.1, 124.6, 22.7, 22.2. HRMS (ESI):m/zcalculated for C23H19NH+: 310.1590, found: 310.1588。
Example 3: 6-chloro-1-methyl-3, 4-diphenylisoquinoline
4-chloro-acetophenone oxime (3) is added into a clean quartz reactor in sequence3.8 mg, 0.20 mmol), tolane (42.7 mg, 0.24 mmol), dichloro (pentamethylcyclopentadienyl) rhodium (III) dimer (6.2 mg, 0.01 mmol), water (0.5 mL), polyethylene glycol 400 (0.5 mL), and a photochemical reaction apparatus with a high-pressure mercury lamp as the light generator, the chamber was stirred at room temperature for 24 hours. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 54.2 mg as a pale yellow solid in a yield of 83%. Melting point: 172-173oC;1H NMR (400 MHz, Chloroform-d) δ8.13 (d,J= 8.9 Hz, 1H), 7.62 (d,J= 1.9 Hz, 1H), 7.52 (dd,J= 8.9, 2.1Hz, 1H), 7.38 – 7.32 (m, 5H), 7.19 (dtt,J= 6.5, 4.9, 2.6 Hz, 5H), 3.05 (s,3H).13C NMR (100 MHz, Chloroform-d) δ 157.7, 150.6, 140.5, 137.1, 136.8,136.4, 131.3, 130.2, 128.4, 127.6, 127.5, 127.4, 127.3, 127.2, 125.1, 124.4,22.7. HRMS (ESI):m/zcalculated for C22H17ClNH+: 330.1044, found: 330.1043。
Example 4: 2, 3-diphenyl-8, 9-dihydro-7H-benzo [ de ]]Quinolines
The method comprises the steps of sequentially adding benzocyclohexane-1-ketoxime (32.2 mg, 0.20 mmol), tolane (42.7 mg, 0.24 mmol), dichloro (pentamethylcyclopentadienyl) rhodium (III) dimer (6.2 mg, 0.01 mmol), water (0.5 mL), polyethylene glycol 400 (0.5 mL) and a high-pressure mercury lamp into a clean quartz reactor, and stirring the mixture for 24 hours in a photochemical reaction instrument chamber of a light generation device at a constant temperature. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 50.2 mg as a bright yellow solid in a yield of 79%. Melting point: 147-148oC;1H NMR (400 MHz, Chloroform-d)δ 7.49 (d,J= 3.9 Hz, 1H), 7.48 (s, 1H), 7.40 – 7.28 (m, 6H), 7.23 (dt,J=7.1, 1.8 Hz, 2H), 7.21 – 7.13 (m, 3H), 3.43 – 3.37 (m, 2H), 3.21 (t,J= 6.1Hz, 2H), 2.29 (p,J= 6.3 Hz, 2H).13C NMR (100 MHz, Chloroform-d) δ 159.3,149.5, 141.1, 138.5, 137.8, 136.3, 131.4, 130.3, 130.0, 129.1, 128.2, 127.6,127.0, 126.9, 124.8, 123.9, 123.6, 34.8, 30.8, 23.5. HRMS (ESI):m/zcalculated for C24H19NH+: 322.1596, found: 322.1596。
Example 5: 1,3, 4-triphenylisoquinoline
Benzophenone oxime (39.4 mg, 0.20 mmol), tolane (42.7 mg, 0.24 mmol), bis (hexafluoroantimonic acid) triacetonitrile (pentamethylcyclopentadienyl) cobalt (III) (5.6 mg, 0.01 mmol), water (0.5 mL), polyethylene glycol 400 (0.5 mL), and a high-pressure mercury lamp were sequentially added to a clean quartz reactor and stirred at room temperature for 24 hours in a photochemical reactor of a light generator. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 56.6 mg as a yellow solid in a yield of 80%. Melting point: 169-171oC;1H NMR (400 MHz, Chloroform-d) δ8.20 (d,J= 8.4 Hz, 1H), 7.87 – 7.82 (m, 2H), 7.74 (d,J= 8.2 Hz, 1H), 7.63– 7.49 (m, 5H), 7.46 – 7.35 (m, 5H), 7.32 (dd,J= 7.5, 1.5 Hz, 2H), 7.23 –7.15 (m, 3H).13C NMR (100 MHz, Chloroform-d) δ 158.8, 148.6, 139.8, 138.7,136.5, 135.9, 130.3, 129.4, 129.2, 128.9, 128.7, 127.5, 127.3, 127.3, 126.5,126.5, 126.3, 126.0, 125.6, 125.0, 124.4. HRMS (ESI):m/zcalculated forC27H19NH+: 358.1596, found: 358.1596。
Example 6: 3, 4-bis (4-methoxyphenyl) -1-methylisoquinoline
Acetophenone oxime (27.0 mg, 0.20 mmol), bis (4-methoxyphenyl) acetylene (57.1 mg, 0.24 mmol), bis (2-methallyl) (1, 5-cyclooctadiene) ruthenium (II) (3.2 mg, 0.01 mmol), water (0.5 mL), polyethylene glycol 400 (0.5 mL), and a high-pressure mercury lamp were sequentially added to a clean quartz reactor and stirred at an internal chamber of a photochemical reactor of a light generator for 24 hours. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 62.9 mg as a yellow solid in a yield of 89%. Melting point: 115-116oC;1H NMR (400 MHz,Chloroform-d) δ 8.18 (dd,J= 5.6, 3.8 Hz, 1H), 7.72 – 7.64 (m, 1H), 7.61 –7.53 (m, 2H), 7.34 (d,J= 8.7 Hz, 2H), 7.15 (d,J= 8.5 Hz, 2H), 6.92 (d,J= 8.5 Hz, 2H), 6.76 (d,J= 8.7 Hz, 2H), 3.85 (s, 3H), 3.77 (s, 3H), 3.07 (s,3H).13C NMR (100 MHz, Chloroform-d) δ 158.6, 158.6, 157.4, 149.1, 136.5,133.6, 132.4, 131.5, 129.9, 129.8, 128.3, 126.3, 126.2, 126.0, 125.5, 113.8,113.2, 55.2, 55.2, 22.7. HRMS (ESI):m/zcalculated for C24H21NO2H+: 356.1651,found: 356.1652。
Example 7: 1-methyl-3, 4-diethylisoquinoline
Acetophenone oxime (27.0 mg, 0.20 mmol), 3-decyne (19.7 mg, 0.24 mmol), dichloro (pentamethylcyclopentadienyl) iridium (III) dimer (8.0 mg, 0.01 mmol), water (0.5 mL), and polyethylene glycol were added sequentially to a clean quartz reactorAlcohol 400 (0.5 mL), high pressure mercury lamp as light generator photochemical reaction instrument chamber temperature stirring 24 hours. After completion of the reaction, saturated brine (10 mL) and ethyl acetate (5 mL. times.3) were added to conduct extraction. The ethyl acetate layer was collected, the solvent was removed under reduced pressure, and the residue was separated and purified by silica gel column chromatography (petroleum ether/ethyl acetate = 50/1, v/v) to give the objective product 29.9mg as a yellow solid in a yield of 75%. Melting point: 123-124oC;1H NMR (400 MHz, Chloroform-d) δ 8.07 (d,J= 8.3 Hz, 1H), 7.97 (d,J= 8.5 Hz, 1H), 7.65 (ddd,J= 8.4, 6.8, 1.2 Hz,1H), 7.49 (ddd,J= 8.1, 6.9, 1.0 Hz, 1H), 3.04 (q,J= 7.6 Hz, 2H), 2.97 (q,J= 7.6 Hz, 2H), 2.91 (s, 3H), 1.34 (t,J= 7.6 Hz, 3H), 1.28 (t,J= 7.6 Hz,3H).13C NMR (100 MHz, Chloroform-d) δ 155.8, 152.6, 135.2, 129.5, 127.2,126.2, 126.1, 125.3, 123.4, 28.5, 22.4, 20.7, 15.3, 15.0. HRMS (ESI):m/zcalculated for C14H17NH+: 200.1439, found: 200.1439。