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Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Regioselective transformation of octaethylporphyrin into a phytoporphyrin analogue
Michio Kunieda1, Yuji Mikata, Hitoshi Tamiaki
1Department of Bioscience and Biotechnology, Faculty of Science and Engineering, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
Abstract:
An octaethylporphyrin derivative, 1, possessing an exo-five-membered ring fused at the 13- and 15-positions was oxidized by osmium tetroxide to give two isomeric chlorins, 3 and 5, possessing beta,beta'-dihydroxy groups at the A- and C-rings, respectively. Single dehydration of 2,3-dihydroxychlorin 3 gave a mixture of 2- and 3-(1-hydroxyethyl)porphyrins 7, while that of 12,13-dihydroxychlorin 5 resulted in the sole formation of 131-hydroxyporphyrin 9. The latter was modified smoothly to the phytoporphyrin analogue 2, whose molecular skeleton was similar to that of naturally occurring chlorophylls possessing a 131-oxo group fixed on an exo-five-membered ring.
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