A reaction of strong electrophilic CF 3-substituted unsaturated compounds with nitrogen containing Π-systems

Abstract

Hexafluoroacetone, esters of trifluoropyruvic acid as well as obtained from the strong electrophilic imines and 1,1-dicyanoethylenes can C-alkylate π-donor aryl amines, nitrogen containing heterocycles and enamines under the mild conditions. For amino group containing compounds this process is complicated by the competitive reaction of N-alkylation. However, its reversibility allows to obtain C-alkylation products. As a rule, the substitution is regiospecific, its orientation not always being ordinary. The reaction products composition and the reaction rates significantly depend on a nucleophylic reagent stereochemical peculiarity. C- and N-alkylation may be accompanied by the formation of CF 3-substituted heterocycles. In some cases the substitution is connected with dehydration dehydro-genation reactions under the effect of unsaturated compounds. The results of a systematic investigation of the above mentioned process as well as special cases of purines and pyrimidines modification will be discussed.