title: Synthesis of chlorophyll-a derivatives methylated in the 3-vinyl group and their intrinsic site energy.
abstract: Wittig reaction of methyl pyropheophorbide-d possessing the 3-formyl group gave readily methyl pyropheophorbides-a bearing a variety of 3-alkenyl groups as semi-synthetic models of chlorophyll-a. The 3-substituents rotated around the C3-C3(1) bond from the coplanar conformation with the chlorin π-system, moving the redmost visible absorption maxima to a shorter wavelength. The model experiments showed that natural chlorophyll-a carrying the 3-vinyl group would take a similar rotamer to control its intrinsic site energy.
authors.affiliation: Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan. Electronic address: tamiaki@fc.ritsumei.ac.jp.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Tamiaki
authors.affiliation: Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan; Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Tsuji
authors.affiliation: Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Kuno
authors.affiliation: Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan; Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kimura
authors.affiliation: Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Watanabe
authors.affiliation: Department of Materials Chemistry, Faculty of Science and Technology, Ryukoku University, Otsu, Shiga 520-2194, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Miyatake
mesh_terms: D002734:Chlorophyll / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D008745:Methylation; D008956:Models, Chemical; D008968:Molecular Conformation; D011166:Porphyrins / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D011166:Porphyrins; D002734:Chlorophyll
keywords: Conformation; Photosynthesis; Pyropheophorbide; Visible absorption maximum; Wittig reaction