@article{59745652b0024c8489697df0584bfb23,
title = "Difluoroboron complexes of peripheral β-diketonates in cyclopheophorbides: Their syntheses and optical properties",
abstract = "Cyclopheophorbide-a prepared from intramolecular mixed Claisen condensation of methyl pyropheophorbide-a (one of the chlorophyll-a derivatives) was complexed with a difluoroboron species at the β-diketonate moiety on the exo-five-membered ring fusing the core cyclic tetrapyrrole π-skeleton. Its 3-substituted chlorin analogs and the related bacteriochlorin were also synthesized by difluoroboronation of the corresponding (bacterio)chlorins possessing a peripheral diketonate group. In solution, all the synthetic complexes showed broad Qy and redmost Soret absorption bands and an intense bluemost Soret band. Their maxima were dependent on the 3-substitution and the 7,8-dihydrogenation. The boron complexes were non-fluorescent, which was comparable to the boron-free counterparts.",
keywords = "Bacteriochlorophyll, Chlorophyll, Coordination, Substitution effect",
author = "Haruki Ishikawa and Ayaka Demise and Yuichi Kitagawa and Yoshinao Shinozaki and Yusuke Kinoshita and Hitoshi Tamiaki",
note = "Funding Information: We thank Dr. Shin Ogasawara of Ritsumeikan University for preparation of drawings. This work was partially supported by Japan Society for the Promotion of Science ( JSPS ) KAKENHI Grant Number JP17H06436 in Scientific Research on Innovative Areas “Innovation for Light-Energy Conversion ( I 4 LEC ){"}. Funding Information: We thank Dr. Shin Ogasawara of Ritsumeikan University for preparation of drawings. This work was partially supported by Japan Society for the Promotion of Science (JSPS) KAKENHI Grant Number JP17H06436 in Scientific Research on Innovative Areas ?Innovation for Light-Energy Conversion ( I4LEC){"}. Publisher Copyright: {\textcopyright} 2021 Elsevier Ltd",
year = "2022",
month = jan,
day = "8",
doi = "10.1016/j.tet.2021.132596",
language = "English",
volume = "104",
journal = "Tetrahedron",
issn = "0040-4020",
publisher = "Elsevier Ltd",
}