Photophysics of a new photosensitizer with high quantum yield of singlet oxygen generation and its application to stereo-selective synthesis of (+)-deoxoartemisinin

Abstract

A new photo-catalyst of [5,10,15-triphenyl-20-(4-methoxycarbonylphenyl)-porphyrin] platinum was synthesized and its photophysical study revealed that it had a high quantum yield of singlet oxygen generation. As an application study, a stereo-specific synthesis of (+)-deoxoartemisinin was performed. The induced high triplet quantum yield (0.96 +/- 0.03) of [5,10,15-triphenyl-20-(4-methoxycarbonylphenyl)porphyrin] resulted the high singlet oxygen quantum yield of 0.90 +/- 0.04. The photo-catalytic effect was compared with that of methylene blue (MB) which was generally used as a photo-catalyst for these types of stereo-specific syntheses of organic compounds. The yield of synthesized (+)-deoxoartemisinin was correlated with singlet oxygen quantum yield. (C) 2009 Elsevier B. V. All rights reserved.