A Thiazole-fused Antiaromatic Compound Containing an s-Indacene Chromophore with a High Electron Affinity

We report on the preparation and characterization of a thiazole-fused polycyclic compound containing an s-indacene chromophore, which has the characteristics of an antiaromatic system. X-ray analysis showed that the fused π-conjugated backbone has a planar structure. Theoretical investigations indicate that the introduction of thiazole rings contributes to decreasing the frontier orbital energy level while permitting the antiaromatic character of the compound to be retained. Physical measurements indicate that the characteristic properties and structures originates from the antiaromatic framework. This study provides an effective method for the chemical modification of s-indacene chromophores with a high electron affinity.