DE1031780B - Process for the preparation of halogenated carbanilides - Google Patents

Description

Process for the production of halogenated carbanilides The invention relates to a process for the production of halogenated carbanilides of the general formula in which R denotes a halogenated benzene hydrocarbon radical whose ortho positions are unsubstituted, and X 'and X "are identical or different and represent chlorine or bromine. Examples of R are: 3 - chlorophenyl, 4 - chlorophenyl, 3 - bromophenyl, 4-bromophenyl , 3,4-dichlorophenyl, 3,4,5-trichlorophenyl, 3,4,5-tribromophenyl, 3-chloro-4-methylphenyl, 4-chloro-3-methylphenyl, 3,5-dichloro-4-methylphenyl, 4-chloro -3,5-dimethylphenyl, 3-chloro-4-ethylphenyl, 3-chloro-4-isopropylphenyl, 3-chloro-4-n-butylphenyl, 3-chloro-4-tert.-butylphenyl, the various chlorobiphenylyls, such as 3 -Chlor-4-biphenylyl and 3-chloro-4- (4-chlorophenyl) -phenyl or the like. R can be a mono- or polyhalogenated benzene hydrocarbon radical which is unsubstituted in the o-positions and which preferably contains no more than three halogen substituents The new compounds in which R is a halogenated benzene hydrocarbon radical that is free from site hosubstituenten (ie in which the 2- and 6-positions are unsubstituted) have valuable properties as bacteriostatics.

The new compounds are obtained according to the invention in that a dihalogenated aniline of the structural formula X '- - N H2 X "-. with an isocyanate of the formula R N C 0 O or that one is a dihalogenated isocyanate of the structural formula X '. -N = C = O X "-with an amine of the formula ROH2, where X', X" and R are the above have given meaning, in the presence of an inert solvent. as inert solvents can be diethyl ether, diisopropyl ether, methyl butyl ether, the liquid alkanes or the like are used. The in making the new Compounds reaction temperatures employed depend on the particular reactants and are generally between room temperature and the reflux temperature of the system.

The new compounds obtained according to the invention have valuable ones Properties as bacteriostatic agents.

The invention is described below with reference to a few exemplary embodiments explained in more detail.

Example 1 In a reaction vessel equipped with a thermometer, a Stirrer and a reflux condenser and 8.1 parts by weight of 3,4-dichloroaniline contained in approximately 57 parts by weight of diethyl ether became a solution dropwise of 7.7 parts by weight (= equimolar amount) of 4-chlorophenyl isocyanate in approximately 15 parts by weight of diethyl ether added at such a rate that a gentle reflux was maintained. After the addition of isocyanate has been completed the reaction mass was stirred for 1 hour. The mass was filtered and the Washed residue with diethyl ether. The dried product consisted of one white flaky solid which, after recrystallization from ethanol, has fine white platelets of 4,3 ', 4'-trichlorocarbanilide, m.p. = 255.2-256.0 ° C (88 O / c yield).

When performing the above procedure but using the 3,4-dichloroaniline by 3,4-dibromo aniline was replaced 4-chloro-3 ', 4'-dibromo-carbanilide, m.p. = 208.5 to 209 ° C.

Example 2 8.1 parts by weight of 3,4-dichloroaniline, approximately 72 parts by weight of diethyl ether and approximately 7.7 parts by weight of 3-chlorophenyl isocyanate introduced and mixed intimately for about 1 hour at room temperature. the The mass was filtered and the residue was washed with diethyl ether. The dried one The product was a white solid which, after recrystallization from ethanol, had white needles of 3,3 ', 4'-trichlorocarbanilide, m.p. 210.7-211.3 ° C (92% yield).

When performing the above procedure but using the 3,4-dichloroaniline was replaced by 3-chloro-4-bromo-aniline, it became 3,3'-dichloro-4'-bromo-carb obtained anilide.

Example 3 4.3 parts by weight of 3,4-dichloroaniline, approximately 72 parts by weight of diethyl ether and approximately 5 parts by weight of 3,4-dichlorophenyl isocyanate introduced and mixed intimately for about 1 hour at room temperature. the The mass was filtered and the residue was washed out with diethyl ether. The dried one Product consisted of a white solid which, after recrystallization from ethanol white grains of 3,4,3 ', 4'-tetrachlorocarbanilide, m.p. = 281 to 282 ° C (100 01o yield), revealed.

Example 4 5.3 parts by weight of 3,4,5-trichloroaniline, approximately 72 parts by weight of diethyl ether and approximately 5 parts by weight of 3,4-dichlorophenyl isocyanate introduced and mixed intimately for about 2 hours at 35 ° C. The crowd became filtered and the residue washed out with diethyl ether. The dried product was a white solid which, after recrystallization from ethanol, had white needles of 3,4,3 ', 4', 5'-pentachlorocarbanilide, m.p. 308-3090 ° C (90.10 /, yield).

The compounds according to the invention of the general formula in which R is a monochlorinated benzene hydrocarbon radical which is free from ortho substituents, have been found to have extremely good bacteriostatic properties.

To illustrate these properties, solutions of 3,3 ', 4'-trichlorocarbanilide and 4,3', 4'-trichlorocarbanilide were combined with solutions of 4,4'-dichlorocarbanilide, 4,2 ', 4'-trichlorocarbanilide (F. = 253.0 to 253.80 C) and 2,4,2 ', 4'-tetrachlorocarbanilide (m.p. = 261 to 263 ° C) compared. The solutions were added to a Sabourard dextrose agar medium in such amounts that concentrations of 10 or 1 and 0.1 parts of the corresponding compound per million parts of agar were obtained. The agar was then poured into a Petri dish in each case, allowed to harden and then inoculated with a standard culture of Micrococcus Pyogenes var. Aureus of normal resistance. Incubation was carried out simultaneously in each case at 37 ° C. for 48 hours. The extent of growth can be seen in the table below. sonocentration Share, íMillion 10 1 1 0.1 4,4'-dichlorocarbanilide. . . . strong strong strong 3,3 ', 4'-trichlorocarbanilide. . no no no 4,3 ', 4'-tricblorcarbanilide. . no no no 4,2 ', 4'-trichlorocarbanilide. . strong strong strong 2,4,2 ', 4'-tetrachloro carbanilide ......... strong strong strong

Claims (1)

PATENT CLAIM: Process for the production of halogenated carbanilides of the general formula in which X 'and X "are identical or different and represent chlorine or bromine and R represents a halogenated benzene hydrocarbon radical whose ortho positions are unsubstituted, characterized in that a dihalogenated aniline' of the structural formula with an isocyanate of the formula R - N = C = 0 or a dihalogenated isocyanate of the structural formula with an amine of the formula RNH2, where X ', X "and R are as defined above, in the presence of an inert solvent. Publications considered: Swiss patent specification No. 215 328.