Benzotrihalides are prepared by pyrolyzing a substituted phenyl trihaloacetate of the formula ##STR1## wherein each X is halo, nitro, alkyloxy, aryloxy, aralkyoxy, cyano, lower alkyl, haloalkyl, haloalkyloxy, alkenyl, haloalkenyl, carbamoyl, N,N-dialkylcarbamoyl, N,N-diarylcarbamoyl, or N,N-diaralkyloxy; Y is halo; and n is an integer of from 1 to 5. As an example, 4-chlorophenyl trichloroacetate is pyrolyzed at 550.degree. C. to 4-chlorobenzotrichloride.
苯并三卤代物可通过热解式为##STR1##的取代苯基三卤
乙酸酯制备,其中每个X是卤素、硝基、烷氧基、芳氧基、芳基烷氧基、
氰基、低烷基、卤代烷基、卤代烷氧基、烯基、卤代烯基、
氨基甲酰、N,N-二烷基
氨基甲酰、N,N-二芳基
氨基甲酰或N,N-二芳基烷氧基;Y是卤素;n为1至5的整数。例如,将4-
氯苯基
三氯乙酸酯在550℃下热解可制得4-
氯苯并三
氯化物。