Fused core-modified planar antiaromatic 32 pi heptaphyrins: Unusual synthesis and structural diversity

Abstract

The condensation reaction of fused dithienothiophene (DTT) diol with a core-modified tripyrrane led to the formation of acid and its concentration dependent products, sapphyrin and heptaphyrin.The single crystal X-ray analysis of sulphur and selenium heptaphyrin exhibits planar conformation owing to fusion. The experimental and theoretical calculations revealed the antiaromatic electronic structure of Hu¨ckel 4np.