Abstract: The invention relates to a process for the synthesis of 1,1-bis(chlorophenyl)-2,2,2-trichloroethanol in (dicofol) from chlorol and chlorobenzene, in which process the acid by-products formed during the condensation reaction of the chloral and the chlorobenzene are used as reaction medium in the final step for synthesis of dicofol.

Abstract: 1,1-Bis(R-phenyl)-2,2,2-trichloroethanes are dehydrochlorinated in high yields, e.g., into 1,1-bis(chlorophenyl)-2,2-dichloroethylenes, by reacting same with an aqueous solution of an alkali metal hydroxide, in liquid state in the presence of a phase transfer agent, e.g., a quaternary ammonium compound, but in the absence of any reaction solvent.

Abstract: 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethanol is separated from a mixture comprising by way of the formation of an addition compound between 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethanol and a moderately electron donating compound, preferably selected from a group formed by dimethyl sulphoxide, cyclohexanone, isophoron, pyridine, 1,4-dioxane, acetic acid, acetonitrile and water.

Abstract: A process for purifying technical grade 1,1-bis(chlorophenyl)-2,2,2-trichloroethanol for reducing its content of DDT related impurities, based on dissolving technical grade dicofol in a mixture of water and a first compound selected from the group formed by ethylene glycol monomethyl ether, acetonitrile, hydroxyacetone or dimethyl sulfoxide, to obtain a solution which is extracted with n-decane, separating the resulting phases. The dicofol extracted with the n-decane is recovered by reextraction of the n-decane phase with mixtures of said first compound and water and the purified dicofol is recovered from the polar phase.