10,15-Bis (ethoxycarbonyl)-5-(4-methoxycarbonylphenyl) B(III)subchlorin: A photosensitizer with high singlet oxygen producing efficiency

Abstract

A novel A2B-type B(III)subchlorin has been synthesized for the first time in two ways possessing two different ester moieties upon macrocyclic periphery from meso-diethoxycarbonyl tripyrrane. Its photophysical and electrochemical properties have been explored. Introduction of the third meso-substituent resulted in the synthesis of the B(III)subchlorin as the major product with the formation of minor oxidized B(III)subporphyrin analogue. This subchlorin derivative was found to generate singlet oxygen much efficiently with quantum yield (φΔ) 0.88.