Metallation of 1,3-bistrifluoromethylbenzene and NN-dimethyl-3,5-bistrifluoromethylaniline

Abstract

The metallation of 1,3-bistrifluoromethylbenzene with the n-butyl-lithium–NNN′N′-tetramethylethylenediamine complex occurs essentially only at the 2-position, but with n-butyl-lithium alone a mixture of products results. n-Butyl-lithium reacts with NN-dimethyl-3,5-bistrifluoromethylaniline mainly at the 4-position. Treatment of 3,5-bistrifluoromethylaniline with aqueous bromine gives a dibromo-compound. Structures are assigned on the basis of 1H n.m.r. data.