A short-step synthesis of 1,6-methano[10]annulene-3,4-dicarboximides and their benzene-, naphthalene-, and thiophene-annulated compounds

Triphenylphosphorane reagents 8 react with 1,3,5-cycloheptatriene-1,6-dicarbaldehyde (2) under acidic as well as basic conditions to produce 1,6-methano[10]annulene-3,4-dicarboximides 1 in moderate -to- good yields. The reagents 8 react with 3,4-arene-annulated 1,3,5-cycloheptatriene-1,6-dicarbaldehydes 9, 10, and 11 to afford only the Wittig condensation products under acidic conditions but produce the arene-annulated annulenedicarboximides under basic conditions. The structures of some of the dicarboximides and the intermediate Wittig condensation products were determined by X-ray structural analysis. The emission properties of the dicarboximides were also studied.