Trifluoroacetylation of 9-methylcarbazole. Example of the formation of a triarylfluoroethane in the heterocyclic series
It is shown that the trifluoroacetylation of 9-methylcarbazole proceeds regio-specifically in the 3 position of the ring. 1,1,1-Tris(9-methyl-3-carbazolyl)-2,2,2-trifluoroethane and 1,1,1′,1′-tetrakis(9-methyl-3-carbazolyl)-2,2,2,2′,2′,-2′-hexafluorodiethyl ether were also isolated from the reaction mixture. Bis(trifluoroacetyl) derivatives were not detected. Only a 3-trifluoroacetyl derivative is formed when the reaction is carried out by heating in the presence of pyridine.