Synthesis of 9,10-bis(trifluoromethyl)benzobarrelenes through reaction of hexafluorobut-2-yne and substituted naphthalenes

Abstract The cycloadducts 9,10-bis(trifluoromethyl)benzobarrelenes were prepared by the reaction of hexafluorobut-2-yne (HFB) with 1- and, 2- substituted naphthalenes in moderate to high yields. In most cases the reaction proceeds with the formation of two isomeric products derived from cycloaddition of HFB to different aromatic rings of the naphthalene system. The individual isomers were isolated by column chromatography and fully characterized. The basic hydrolysis of ester derivatives of the various 9,10-bis(trifluoromethyl)benzobarrelenes provided the corresponding acids.