Synthesis, Photophysical and Electrochemistry of Near-IR Absorbing Bacteriochlorins Related to Bacteriochlorophyll a

详细信息    查看全文

• 作者：Andrei Kozyrev ; Manivannan Ethirajan ; Ping Chen ; Kei Ohkubo ; Byron C. Robinson ; Kathleen M. Barkigia ; Shunichi Fukuzumi ; Karl M. Kadish ; Ravindra K. Pandey
• 刊名：The Journal of Organic Chemistry
• 出版年：2012
• 出版时间：November 16, 2012
• 年：2012
• 卷：77
• 期：22
• 页码：10260-10271
• 全文大小：582K
• 年卷期：v.77,no.22(November 16, 2012)
• ISSN：1520-6904

文摘

A series of new bacteriochlorins was synthesized using 13²-oxo-bacteriopyropheophorbide a (derived from bacteriochlorophyll a) as a starting material, which on reacting with o-phenylenediamine and 1,10-diaminonaphthalene afforded highly conjugated annulated bacteriochlorins with fused quinoxaline, benzimidazole, and perimidine rings, respectively. The absorption spectra of these novel bacteriochlorins demonstrated remarkably red-shifted intense Q_y absorption bands observed in the range of 816鈥?50 nm with high molar extinction coefficients (89,900鈥?36,800). Treatment of 13²-oxo-bacteriopyropheophorbide a methyl ester with diazomethane resulted in the formation of bacterioverdins containing a fused six-membered methoxy-substituted cyclohexenone (verdin) as an isomeric mixture. The pure isomers which exhibit long-wavelength absorptions in the near-IR region (865鈥?90 nm) are highly stable at room temperature with high reactivity with O₂ at the triplet photoexcited state and favorable redox potential and could be potential candidates for use as photosensitizers in photodynamic therapy (PDT).