Abstract The reactions of benzotrichloride with methyl and ethyl esters and nitriles of 2- thiophenecarboxylic and 2-furancarboxylic acids, with 2-acetylthiophene, 2-acetylfuran, and 2-thiophenaldehyde in the presence of an excess of anhydrous aluminum chloride have been studied. The phenyldichloromethyl group enters into position 4 of the thiophene and position 5 of the furan ring and on treating the reaction mixture with water is converted to ...