GB2072654A - Ortho-haloalkyl-2-haloacetanilide derivatives which are intermediates in the preparation of 2-haloacetanilide herbicides - Google Patents

Abstract

The invention herein relates to novel ortho-haloalkyl-2-haloacetanilide compounds of the formula <IMAGE> wherein X is Cl, Br or I; R is H, CH3, CF3, t.C4H9 or -CX1X2R2; R2 in H, Cl, Br or straight chain C1-4 alkyl; Y1 and Y2 are independently H, halogen, CH3, CF3, t.C4H9 or -CX1X2R2; X1 and X2 are independently H, Cl or Br provided that (i) R2 = X1 = X2 @ Cl or Br and (ii) when R2 is alkyl X1 and X2 are not both simultaneously H, Cl or Br and their method of preparation by halogenation in the side chain. The compounds are useful as intermediates in the preparation of N-substituted-2',6'-disubstituted- 2-haloacetanilide derivatives which selectively control undesired vegetation in agricultural crops.

Description

SPECIFICATION Ortho-haloalkyl-2-haloacetanilide derivatives which are intermediates in the preparation of 2-haloacetanilide herbicides Background of the Invention The invention relates to novel ortho-(haloalkyl)-2-haloacetanilide derivatives and to their method of preparation. The novel compounds are useful as intermediates in the preparation of certain ortho (alkoxymethyl)-2-haloacetanilide derivatives which exhibit selective herbicidal activity.

Description of the PriorArt U. S. Patent No. 4,070,389 generically discloses the herbicidal use of certain chloroacetanilides among which are certain N-substituted-2',6'-(haloalkyl)-2-chloroacetanilides. However, U. S. Patent No. 4,070,389 does not teach one skilled in the art how to make or use the aforementioned compounds but refers skilled artisans to certain German "Offenlegungsschriften" for their preparation and use. Mentioned are the following references: DOS No's. 2,212,268,2,305,495, 2,328,340, 2,402,983,2,405,183 and 2,405,479. Those skilled in the art will recognize that none of the above-mentioned references disclose N-substituted-2'-6' (haloalkyl)-2-chloroacetanilides. The only reference which remotely suggests said compounds is DOS No.

2,405,479, which corresponds to British Patent No. 1,455,474.

British Patent No. 1,455,474 generically discloses the herbicidal use of N-(2-methoxyethyl) or N-(2 ethoxyethylS2'-(trifluoromethyl)-6'-alkyl-2-chloroacetanilides. (Also exemplary of this type of acetanilide is U.S. Patent No. 4,152,137). There is no teaching in British Patent No. 1,455,474 of compounds of the type claimed herein, i.e., N-methyl, N-(bromomethyl)- or N-(chloromethyl)-ortho-(haloalkyl)-2-haloacetanilides.

As to the method of preparing the compounds of the British reference, the phenyl ring substituents of the compounds disclosed by said reference must be introduced on the ring before reactions at the amino group are effected. That is, appropriately substituted aniline materials are reacted to give the desired haloacetanilides. There is no teaching in said reference of the novel process disclosed and claimed herein, i.e., the selective halogenation of ortho ring substituents and/or the N-alkyl substituent group of 2-haloacetanilides.

The prior art discloses the bromination of ortho-methylacetanilide using N-bromosuccinimide (NBS). [E.

G. Kleinschmidt, et al, PHARMAZIE, 24(2), pages 87-94, 1969]. However, contrary to the novel process claimed herein, the bromination process described in the aforementioned reference occurs entirely on the phenyl ring, i.e., only nuclear bromination is observed when the ring is ortho-alkyl substituted.

Ulrich et al, J. ORG. CHEM., 39(19), pages 2897-2899, 1974 discloses the preparation of N-(chloromethyl) N-phenylcarbamoylchloride via the monochlorination of N-methyl-N-phenylcarbamoylchloride, in the presence of ultraviolet light.

Description of the Invention The present invention relates to certain ortho-(haloalkyl)-2-haloacetanilides which are intermediates in the preparation of certain substituted ortho-(alkoxymethyl)-2-haloacetanilide derivatives which are useful herbicides.

The compounds of the present invention have the formula

where n is equal to zero or one; when n is equal to one; X is equal to chloro, bromo or iodo; R is equal to hydrogen, methyl, chloromethyl or bromomethyl; R1 is equal to hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

R2 is equal to chloro, bromo or straight chain alkyl containing 1 to 4 carbon atoms; Y1 and Y2 independently equal hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

X1 and X2 independently equal hydrogen, chloro or bromo moieties, provided that when R2 is equal to straight chain alkyl containing 1 to 4 carbon atoms, only one of X1 and X2 may equal hydrogen, chloro or bromo and further provided that R2, X1 and X2 may not simultaneously equal chloro or bromo; when n is equal to zero, R is equal to chloromethyl;R1 is equal to hydrogen, trifluoromethyl or halogen; Y1 and Y2 independently equal hydrogen or halogen; R2 is equal to hydrogen. Compounds of the above formula are novel where n is equal to one.

When used herein, the phrase "straight chain alkyl containing 1 to 4 carbon atoms" refers to methyl, ethyl, n-propyl and n-butyl.

The term "halogen" refers to chlorine, bromine, fluorine and iodine atoms. Chlorine and bromine are preferred for use in the present invention.

The compounds of the present invention are prepared according to the following novel process:

In the compounds of Formula I, n, X, R, R1, R2, X1, X2, Y, and Y2 have the meanings previously described.

In the compounds described by Formula II, the following meanings are ascribed to the various substituent groups: where n is equal to one, R, X, Y1 and Y2 have the meanings previously described; R" is equal to hydrogen, halogen, tert-butyl, trifluoromethyl or

R"' is equal to hydrogen or straight chain alkyl containing 1 to 4 carbon atoms; where n is equal to zero, R is equal to methyl; R" is equal to hydrogen, trifluoromethyl or halogen; Y, and Y2 independently equal hydrogen or halogen; R"' is equal to hydrogen.

In accordance with the above reaction scheme the appropriate starting material, i.e., a compound of the type described by Formula II is dissolved in a suitable volume of a solvent inert to halogenation. Examples of suitable solvents are carbon tetrachloride, chloroform, petroleum ether, methylene chloride and the like.

Preferred for use herein is carbon tetrachloride. At this point, a catalyst, e.g., benzoyl peroxide, may be added to the mixture to facilitate the reaction. The use of said catalyst is, however, optional, and is not necessary to the practice of the process. To this mixture is added a stoichiometric equivalent amount of a halogenating agent selected from the group consisting of molecular chlorine, molecular bromine, N-bromosuccinimide (NBS) or other N-bromo equivalents, as for example, N-bromo-N-methylacetamide or N-bromophthalimide. It will be recognized that greater than stoichiometric equivalent amounts of halogenating agent may be used in the practice of the present process with equal facility. The resulting mixture is subjected to external and/or internal ultraviolet and/or white light and the reaction allowed to proceed.The reactants are usually admixed at room temperature, i.e., about 25"C and thereafter maintained at or near reflux. However, lower temperatures can be employed as is illustrated in the following examples.

The separation of the resulting reaction product from the reaction mixture is readily accomplished by conventional means. For example, unreacted halogenating agent and succinimide can be removed by filtration while the solvent may be removed by stripping or distillation, preferably low temperature vacuum distillation. The product is usually purified by crystallization from suitable solvents.

The starting materials, i.e., the compounds of Formula II are known in the art, e.g., from U. S. Patent No.

3,442,945, 3,637,847, 3,966,811 and from British Patent No. 1,455,474.

In the process described above, chlorination or bromination of ortho-alkyl-2-haloacetanilides, as opposed to ortho-alkoxy-2-haloacetanilides does not give halogenation of the phenyl ring, i.e., nuclear halogenation.

When halogenation is carried out with molecular chlorine using 2'6'-dimethyl-N-methyl-2-chloroacetanilide as the starting material, both the N-methyl and ring (benzylic) methyl groups chlorinate at comparable rates.

When the ortho-alkyl-2-chloroacetanilides disclosed herein are subjected to bromination, the process is slower and more selective than chlorination. Thus, for optimum results, molecular bromine (dissolved in CC14) is added dropwise to a refluxing and illuminated, (IlV and/or white light) solution of amide containing about 0.1% benzoyl peroxide. In general, when 2-halo-N-methyl-2',6'-dialkyl-acetanilides are brominated using Br2, only the phenyl ring (benzylic) side-chain carbons brominate.

Bromination with molecular bromine (Br2) of 2-chloroacetanilides of the type described by Formula II gives rise in varying degrees to halogen interchange, with partial formation of 2-bromacetanilides. Secondary and tertiary anilides are susceptible to this interchange when prepared in large amounts at higher bromine and amide concentrations. The bromine found at the 2-position stems from interchange of chlorine with HBr to give HCI. Halogen interchange may be minimized by nitrogen sparging to aid hydrogen bromine (HBr) removal.

To avoid halogen interchange and still derive the benefits accruing to bromination, recrystallized N-bromosuccinimide (NBS) or a similar N-bromo equivalent, as, e.g., N-bromo-N-methylacetamide or N-bromophthalimide, with optionally added benzoyl peroxide, is the reagent of choice. Merely equimolar amounts of this conveniently handled material is necessary to afford exclusive side-chain benzylic bromination, with the generation of by-product succinimide.

Molecular bromine or NBS brominates an ortho-methyl group exclusively in the presence of an ortho-t-butyl group. Chlorine, on the other hand, is not as selective, with some chlorination of the t-butyl moiety.

The manner in which the compounds of the present invention can be prepared is more specifically illustrated in the following examples EXAMPLE 1 Preparation of 2' 6'-bisf 1-Bromoethyl)-2-Bromo-N-Methylacetanilide.

2-Chloro-N-methyl-2',6'-diethylacetanilide (23.9 g, 0.1 mol) was placed in 300 ml of carbon tetrachloride witch 0.2 g benzoyl peroxide. After heating to reflux, 16.0 g of bromine (0.2 mol) in 50 ml CCl4was added dropwise to the mixture which was thereafter subjected to both internal uV and external white light. Solvent was removed in vacuo and the crude product was dissolved in ethyl acetate. The solid product was repeatedly recrystallized from ethyl acetate to give 2',6'-bis(1 -brnmoethyl)-2-brnmo-N-methyl-acetanilide, mp 162-164 C.

Anal. Calc'd. for C13H16Br3NO: C, 35.32; Br, 54.24; N, 3.17.

Found: C, 35.18; Br, 54.29; N, 3.16.

EXAMPLE 2 Preparation of 2'-rBromomethylJ-6'-t-Butyl-2-Bromo-N-Methylacetanilide To 38.0 g (0.15 mol) of 2-chloro-N,2'-dimethyl-6'-t-butylacetanilide (33 g, 0.15 mol) dissolved in CC14 was added 0.2 g of benzoyl peroxide and the mixture heated to reflux. Bromine (24.0 g, 0.15 mol) in 50 ml CC14 was added dropwise to the above mixture, after addition (1-1/2 hour) and further reflux (1/2 hour), the material was stripped to remove solvent. On scratching the residue solidified. The product was recrystallized from heptane and identified as 2'-(bromomethyl)-6'-t-butyl-2-bromo-N-methylacetanilide, mp 86-87"C, yield 65%.

Anal. Calc'd, for C14H19Br2NO: C, 44.59; Br, 42.38; N, 3.71.

Found: C, 44.62; Br, 42.27 N, 3.72 EXAMPLE 3 Preparation o2-chIoro-N,2' 6'-fris{BromomethyI)acetaniIide 2-chloro-N-(chloromethyl)-2',6'-dimethylacetanlide (0.04 mol, lOg) was placed in 100 ml CC14 containing 0.14 g benzoyl peroxide and the mixture heated to reflux with internal 0.2 amp UV illumination and 150 watt exterior white light. To this mixture was added 13 g bromine contained in 50 ml CCl4, after theory bromine was added, 3.0 g additional bromine was added. The mixture was cooled, solvent removed and resulting viscous oil triturated with ether to give a solid, which by nmr indicated crude 2-chloro-N-2',6'tris(bromomethyl)acetanilide.The crude product was not further purified but was thereafter treated with 200 ml of boiling methanol, to yield 2',6'-bis(bromomethyl)-2-chloro-N-(methoxymethyl)acetanilide, mp 127.5 129"C.

EXAMPLE 4 Preparation of 2'-(Bromomethyl-2-Chloro-6'-t-Butylacetanilide 2-Chloro-2'-methyl-6'-t-butylacetanilide, (5.6 g, 0.025 mol) was placed inca 120 ml CCl4with 0.15 g benzoyl peroxide and heated to reflux. Bromine (4.0 g, 0.025 mol) in 50 ml CC14 was added dropwise. After addition, reaction as monitored by nmr appeared complete. After vacuum removal of solvent, 7.0 g of a white solid was recovered. After successive recrystallization from isopropanol, the product, 2'-(bromomethyl)-2-chloro6'-t-butylacetanilide melted at 142-147"C, yield 88%.

Anal. Calc'd. for C13H17BrCl NO: C,49.00; Br, 25.08; Cl, 11.13.

Found: C, 47.93; Br, 24.50; Cl, 10.83.

EXAMPLE 5 Preparation of 2-Chloro-N,2' 6'-tris{Chloromethyl)acetanilide 2-chloro-N,2',6'-tri-methyiacetanilide (21.1 g, 0.1 mol) was placed in 200 ml CC14 and an internal 0.2 amp uV source illuminated within the 500 ml flask; chlorine (0.1 mol, 7.0 g) was introduced subsurface with stirring. The reaction was mildly exothermic, with temperature climbing from 20 to 40"C. After all chlorine had been added, an essentially colorless solution was obtained. The mixture was cooled to ca 5 C and another 0.1 mol chlorine added. Finally, a third molar equivalent of chlorine was added to the mixture. The material was permitted to stand ca 48 hours. Thereafter, solvent was removed to give a viscous oil.Portions ofthis oil were recrystallized from pentane-etherto give crystals identified as 2-chloro N,2',6'tris(chloromethyl)acetanilide, mp 70-75"C. The crude product was not further purified but was directly treated with boiling methanol to produce 2-chloro-N-(methoxymethyl)-2',6'bis(chloromethyl)acetanilide.

The compound of Example 5 may also be prepared utilizing 2-chloro-N-(chloromethyl)-2',6'- dimethylacetanilide as the starting material.

EXAMPLE 6 Preparation of 2'-(Bromomethyl)-6'-t-Butyl-2-Chloro-N-(Chloromethyl)acetanilide.

To 17.3 g (0.06 mol) of 2-chioro-N-chloromethyl-2'-(methyl)-6'-(t-bufyl)-acetanilide dissolved in 250 ml CC14 was added 11.2 g (0.063 mol) recrystallized N-bromosuccinimide (NBS) and 0.25 g benzoyl peroxide. The resulting mixture was heated to reflux and the 500 ml 3-necked r.b. flask illuminated by low amperage immersible uV and exterior white light. The reaction as monitored by nmr was essentially complete in ca 0.5 hour. On standing at room temperature for ca. 48 hours, 2.2 g of the product, 2'-(bromomethyl)-6'-t-butyl 2-chloro-N-(chloromethyl)acetanilide, mp 124-1 250C was isolated. An additional amount (7.9 g) was recovered on partial evaporation of the solvent. The product was not further purified but reacted with methanol to yield 2'-(bromomethyl)-2-chloro-N-(methoxymethyl)acetanilide.

EXAMPLE 7 Preparation of 2'-rBromomethyl)-6'-z-Butyl-2-Chloro-N-Methylacetanilide 2-chloro-6'-t-butyl-N,2'-dimethylacetanilide (17.5 g, 0.069 mol) was dissolved in 250 ml CCl4with 0.2 g benzoyl peroxide and 13 g (0.072 mol) recrystallized NBS using illumination and flask size as described in Example 6. The reaction was completed in ca. 1/2 hour, with succinimide floating on top of the CC14 solution.

The material was filtered and the filtrate washed with water, then vacuum treated to remove solvent to give 24.9 g residue. The residue was recrystallized from hexane to give 14.8 g of product, a second recrystallization from hexane yielded 2'-(bromomethyl)-6'-t-butyl-2-chloro-N-methylacetanilide, mp. 112 114 C; yield 63%.

Anal. Calc'd. for C14H19BT Cl NO: C, 50.54; Br, 24.02; Cl, 10.66 Found: C, 50.33; Br, 24.63; Cl, 10.61.

EXAMPLE 8 Preparation of 2'-(Chloromethyl)-6'-Methyl-2-Chlornacetanilide 2',6'-dimethyl-2-chloroacetanilide was chlorinated according to the procedure described in Example 5 to yield a white solid identified as 2'-(chloromethyl)-6'-methyl-2-chloroacetanilide, m.p. 133-134 C.

Anal. Calc'd for C10H11Cl2NO: C, 51.74; H, 4.77, N, 6.03; Found: C, 51.69; H,4.66; N,6.03 EXAMPLE 9 Preparation of 2,6'-bistBromomethyl)-2-Chloro-N-{Chloromethyl)acetanilide 2-chloro-N-(chloromethyl)-2',6'-dimethylacetanilide (10.0 g, 0.04 mol) was dissolved in 100 ml of CC14 with 0.14g of benzoyl peroxide. The material was heated to reflux and the flask illuminated by low amperage immersible uV and exterior white light. To the mixture was added dropwise 13.0 g of molecular bromine contained in 50.0 ml of CC14. 3.0 g of additional bromine was added when nmr indicated the reaction was nearly complete. The mixture was cooled and the solvent removed in vacuo.The resulting viscous oil was triturated with ether to give a solid, identified as 2',6'-bis(bromomethyl)-2-chloro-N (chloromethyl)acetanilide. The product was not further purified but was treated with boiling methanol to give 2',6'-bis(bromomethyl)-2-chloro-N-(methoxymethyl)acetanilide.

EXAMPLE 10 Preparation of2 '- lDibromom ethyll-6'-t-Butyl-2-Chloroacetanilide The compound of Example 4 (9.54 g, 0.03 mol) was added to 300 ml of CC14 containing 0.3 g benzoyl peroxide. Two (2) white lights were used to irradiate the reaction vessel. Thereafter, 4.8 g bromine in 50 ml of CC14 were added dropwise to the irradiated mixture while maintaining a gentle nitrogen gas sparge in the reaction medium. Irradiation source was removed after about 1-1/2 hours and the mixture was permitted to stand and cool overnight. The solid precipitate was filtered to give 10.4 g first crop, 1.4 g second crop. The solid material was recrystallized from isopropanol to yield 2'-(dibromomethyl)-6'-t-butyl-2-chloroacetanilide, mp 145-147"C, yield 99%.

Anal. Calc'd for C13H16Br2CI NO: C, 39.28; H, 4.06; N, 3.52.

Found: C,38.99; H,4.10; N,3.58.

EXAMPLE 11 Preparation of2'-(Brnmomethv')-Z 6'-Dichloroacetanilide To 300 ml of CC14 in a 500 ml flask was added 15.0 g of 2,6'-dichloro-2'-methylacetanilide (0.068 mol) and 0.5 g of benzoyl peroxide. The reaction vessel was irradiated by two exterior white lights. The reaction mixture was heated to reflux and thereafter 10.9 g of bromine (Br2) in 50 ml CCl4 was added dropwise with nitrogen sparging. An additional 2.5 g of Br2 was added when nmr monitoring indicated that reaction was incomplete. Solvent was removed in vacuo and the crude solid was recrystallized from isopropanol and thereafter vacuum sublimated (0.05 mm) to yield 2'-(bromomethyl)-2,6'-dichloroacetanilide, mp 155-159"C, yield 58%.

Anal. Calc'd for CgH8BrCI2 NO: C, 36.40; H, 2.72; N, 4.72.

Found: C, 36.18, H, 2.72; N, 4.80.

EXAMPLE 12 Preparation of 2'-rBromomethyl)-2,3'-Dichloro-6'-f-Butylacetanilide In a 1 liter flask, 2,3'-dichloro-2'-methyl-6'-t-butylacetanilide (15. g, 0.055 mol) was dissolved in 600 ml CC14. Irradiation was provided by two exterior white lights. The reaction mixture was heated to reflux and thereafter 8.8 g of molecular bromine in 50 ml CC14 was added dropwise. Excess solvent was removed in vacuo and the solid product was twice recrystallized to yield 2'-(bromomethyl)-2,3'-dichloro-6'-tbutylacetanilide, mp 182-184"C, yield 65%.

Anal. Calc'd for C13H16BrCl2 NO: C, 44.22; H, 4.57; N, 3.97.

Found: C, 44.09; H, 4.62 N, 3.96.

EXAMPLE 13 Preparation of 2 ' 3'-bis{Bromomethyl)-2-Chloro-6'-t-Butylacetanilide In a liter flask 15 g (0.059 mol) of 2-chloro-2',3'-dimethyl-6'-t-butylacetanilide was dissolved in 600 ml CC14.

Irradiation was provided with two white flood lights. The reaction mixture was heated to reflux, sparged with nitrogen and thereafter 9.44 g (0.059 mol) of elemental bromine in 50 ml CC14 was added dropwise. After a second molar equivalent of molecular bromine was added, and after ca. 48 hours, the reaction mixture was filtered and the solid recrystallized from isopropanol to yield 2',3'-bis(bromomethyl)-2-chloro-6'-tbutylacetanilide, mp 180-182"C (vacuum sublimation mp 195-197"C).

Anal. Calc'd for C14H18Br2CI NO: C, 40.85; H, 4.41; N, 3.40.

Found: C, 40.60; H, 4.37; N, 3.40.

EXAMPLE 14 Preparation of 2'-(Bromomethyl)-2-Chloroacetanilide 2-chloro-2'-methylacetanilide (4.0 g, 0.02 mol) and N-bromosuccinimide (3.9 g, 0.02 mol) were dissolved in 300 ml of CC14 with 0.3 g of 2,2'-azobis[2-methyl-propionitrile]. The mixture was illuminated with a spotlight and heated to reflux for 2-1/2 hours. At this time the mixture was allowed to cool to room temperature whereupon it was filtered, washed once with water, dried over MgSO4, filtered again and stripped to yield a white solid. The solid was recrystallized from toluene to yield 2.2 g of product, 2'-(bromomethyl)-2chloroacetanilide, mp 125-127"C, yield 38%.

Anal. Calc'd. for CgHgBrCI NO: C, 41.17; H, 3.46; N, 5.34.

Found: C, 41.35; H, 3.40; N, 5.30.

EXAMPLE 15 Preparation of 2'-rBromomethyl)-6'-{Trifluoromethyl)-2-Chloroacetanilide To 12.5 g (0.05 mol) of 2'-methyl-6'-(trifluoromethyl)-2-chloroacetanilide was added 300 ml of carbon tetrachloride and 10.0 g (0.056 mol) of recrystallized NBS in a 1 liter flask. The mixture was maintained at room temperature for ca. 1 - 1-1/2 hours and thereafter maintained at 70-75"C for ca. 4-5 hours. The crude produced was isolated as a solid (vessicant) 17.7 g; recrystallization from isopropanol yielded 9.8 g of product, 2'-(bromomethyl)-6'-(trifluoromethyl)-2-chloroacetanilide, mp 93-101"C, 59.4% yield.

Anal. Calc'd for C,OH8CIBrF3O: C, 36.34; H, 2.44 N, 4.24.

Found: C, 35.94; H, 2.27 N, 4.19.

EXAMPLE 16 Preparation of 2-Chloro-N-Chloromethylacetanilide To a suitable flask fitted with a stirrer, gas delivery tube, thermometer and interior, low pressure uV light was charged 200.0 ml of a CC14 solution containing 0.1 mol of 2-chloro-N-methylacetanilide. A molar equivalent of gaseous chlorine was slowly introduced at room temperature into the flask. The solution was thereafter illuminated and after a short induction period, the temperature of the solution rose to 38DC due to the exotherm of chlorination. Nmr of the CCI4 solution showed complete reaction after a 10% excess of chlorine had been introduced.Upon vaccum treatment to remove gases and solvent a 98% yield of 2-chloro-N-(chloromethyl)acetanilide was obtained as a heat-sensitive oil, which possessed the following nrm: 0 (CDCl3), b 3.9 (s, 2H, CICH2C), b 5.55 (s, 2H, CICH2N), 67.6 (broad s, 5H, ArH).

The compounds of the present invention have been found to exhibit herbicidal activity as well as being useful as intermediates in the preparation of certain ortho-(alkoxymethyl)-2-haloacetanilides which are effective herbicides. The process by which these latter compounds are prepared involves reacting the previously described compounds of Formula I with an alcohol preferably in the presence of metal cations, e.g., potassium, sodium, silver, lead, mercury, etc., or other Lewis acids, e.g., AICI3, SnCl4, ZnCl2, etc. Using the novel compounds of Formula lit was found that the halogen on the ortho-haloalkyl groups, especially halomethyl, attached to the ring (benzylic) portion of the 2-haloacetanilide molecule of Formula I, could be selectively replaced by an appropriate alcohol without disturbing the otherwise labile 2-acetyl halogen.

Although this invention has been described with respect to specific modification, the details thereof are not be be construed as limitations, for it will be apparent that various equivalents, changes and modifications may be resorted to without departing from the spirit and scope thereof and it is understood that such equivalent embodiments are intended to be included herein.

Claims (43)

1. A compound having the formula

where X is chloro, bromo or iodo; R is hydrogen, methyl, chloromethyl or bromomethyl; R, is hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

R2 is hydrogen, chloro, bromo or straight chain alkyl containing 1 to 4 carbon atoms; Y1 andY2 independently equal hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

X1 and X2 independently equal hydrogen, chloro or bromo moieties, provided that when R2 is straight chain alkyl containing 1 to 4 carbon atoms, only one of X1 and X2 may equal hydrogen, chloro, bromo and further provided that R2, X1 and X2 may not simultaneously equal chloro or bromo.

2 A compound according to Claim 1 wherein R2 is chloro or bromo.

3. A compound according to Claim 2 wherein X1 is chloro or bromo and X2 is hydrogen.

4. A compound according to Claim 3 wherein Y1 andY2 are equal to hydrogen.

5.. A compound according to Claim 4 wherein R1 is hydrogen, methyl, chloromethyl, bromomethyl, tert-butyl or trifluoromethyl.

6. A compound according to Claim 5 wherein R1 is trifluoromethyl.

7. A compound according to Claim 5 wherein R1 is chloromethyl or bromomethyl.

8. A compound according to Claim 5 wherein R1 is methyl or tert-butyl.

9. A compound according to Claim 5 wherein R is methyl, chloromethyl or bromomethyl.

10. A compound according to Claim 1 wherein Y1 is hydrogen andY2 is chloro, bromo or methyl.

11. A compound according to Claim 1 wherein R2 is bromo, X1 and X2 are hydrogen and R1 is equal to t-butyl.

12. A compound according to Claim 1 wherein R is hydrogen, R1 is trifluoromethyl, Y1, Y2, X1 and X2 are hydrogen and R3 is chloro or bromo.

13. A compound according to Claim 1 wherein said compound is 2'-(brnmomethyl)-2-chlorn-6'- (trifluoromethyl) acetanilide.

14. A compound according to Claim 1 wherein said compound is 2-chloro-2'-(chloromethyl)-6'- (trifluoromethyl)acetanilide.

15. A compound according to Claim 1 wherein said compound is 2'-(bromomethyl)-2-chloro-6'-methyl acetanilide.

16. A compound according to Claim 1 wherein said compound is 2-chloro-2'-(chloromethyl)-6'-methyl acetanilide.

17. A compound according to Claim 1 wherein said compound is 2-chloro-2'-(dichloromethyl )-6' (trifluoromethyl)acetanilide.

18. A process for preparing compounds having the formula

wherein n is zero or one; when n is one, X is chloro, bromo or iodo; R is hydrogen, methyl, chloromethyl or bromomethyl; R1 is hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

R2 is hydrogen, chloro, bromo or straight chain alkyl containing 1 to 4 carbon atoms; Y1 and Y2 independently equal hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

X1 and X2 independently equal hydrogen, chloro or bromo moieties, provided that when R2 is equal to straight chain alkyl containing 1 to 4 carbon atoms, only one of X1 and X2 may equal hydrogen, chloro or bromo; and further provided that R2, Xr and X2 may not simultaneously equal chloro or bromo; when n is zero, R is chloromethyl, R1 is hydrogen, trifluoromethyl or halogen, Y1 and Y2 independently equal hydrogen or halogen and R2 is hydrogen, which comprises reacting a compound having the formula

wherein n is equal to zero or one; when n is equal to one; R, X, Y1 and Y2 are as defined in Formula I; R" is equal to hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

R"' is equal to hydrogen or straight chain alkyl containing 1 to 4 carbon atoms; when n is equal to zero, R is equal to methyl, R" is equal to hydrogen, trifluoromethyl or halogen; Y1 and Y2 independently equal hydrogen or halogen and R is equal to hydrogen; with a halogenating agent in the presence of a solvent insert to halogenation and in the presence of irradiation from an ultraviolet and/or white light source.

19. A process according to Claim 18 wherein the solvent is carbon tetrachloride.

20. A process according to Claim 19 wherein said halogenating agent is molecular chlorine.

21. A process according to Claim 19 wherein said halogenating agent is molecular bromine.

22. A process according to Claim 19 wherein said halogenating agent is N-bromosuccinimide.

23. A process according to Claim 18 wherein the compound of Formula lln is one.

24. A process according to Claim 23 wherein in the compound of Formula II R" is hydrogen, halogen, methyl, tert-butyl, trifluoromethyl or

and wherein R"' is equal to hydrogen.

25. A process according to Claim 24 wherein in the compound of Formula II R" is methyl, chloro, t-butyl or trifluoromethyl.

26. A process according to Claim 25 wherein in the compound of Formula II R" is methyl.

27. A process according to Claim 25 wherein in the compound of Formula II R" is trifluoromethyl.

28. A process according to Claim 25 wherein in the compound of Formula II R" is tert-butyl.

29. A process according to Claim 25 wherein in the compound of Formula II Y1 and Y2 are hydrogen.

30. A process according to Claim 25 wherein in the compound of Formula II Y1 is hydrogen and Y2 is equal to chloro.

31. A process according to Claim 19 wherein in the compound of Formula II R"' is straight chain alkyl containing 1 to 4 carbon atoms.

32. A process according to Claim 31 wherein in the compound of Formula II R"' is ethyl.

33. A process according to Claim 18 wherein the temperature of the reaction is at or near reflux temperature.

34. A process according to Claim 18 wherein in the compound of Formula II n is zero.

35. A process according to Claim 34 wherein in the compound of Formula II R", Y1 andY2 are hydrogen.

36. A process according to Claim 34 wherein in the compound of Formula II R" is chloro or bromo and Y, andY2 are hydrogen.

37. A process according to Claim 34 wherein in the compound of Formula II R" is trifluoromethyl andY1 and Y2 are hydrogen.

38. A process according to Claim 18 wherein the compound of Formula I is 2'-(bromomethyl)-2-chloro-6'- (trifluoromethyl)acetanilide.

39. A process according to Claim 18 wherein the compound of Formula I is 2-chloro-2'-(chloromethyl)-6'- (trifluoromethyl)acetanilide.

40. A process according to Claim 18 wherein the compound of Formula I is 2'-(bromomethyl)-2-chloro-6'mefhylacetanilide.

41. A process according to Claim 18 wherein the compound of Formula I is 2-chloro-2'-(chloromethyl)-6'- methylacetanilide.

42. A process according to Claim 18 wherein the compound of Formula I is 2-chloro-2'-(dichloromethyl)6'-(trifluoromethyl)acetanilide.

43. A process according to Claim 18 wherein the compound of Formula I is 2-chloro-N-(chloromethyl)- acetanilide.