title: Peripherally Silylated Porphyrins.
abstract: Silylation of peripherally lithiated porphyrins with silyl electrophiles has realized the first synthesis of a series of directly silyl-substituted porphyrins. The meso-silyl group underwent facile protodesilylation, whereas the β-silyl group was entirely compatible with standard work-up and purification on silica gel. The meso-silyl group caused larger substituent effects to the porphyrin compared with the β-silyl group. Silylation of β-lithiated porphyrins with 1,2-dichlorodisilane furnished β-to-β disilane-bridged porphyrin dimers. A doubly β-to-β disilane-bridged Ni(II)-porphyrin dimer was also synthesized from a β,β-dilithiated Ni(II)-porphyrin and characterized by X-ray crystallographic analysis to take a steplike structure favorable for interporphyrinic interaction. Denickelation of β-silylporphyrins was achieved upon treatment with a 4-tolylmagnesium bromide to yield the corresponding freebase porphyrins.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku Kyoto, 606-8502 (Japan), Fax: (+81) 75-753-3970.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kato
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku Kyoto, 606-8502 (Japan), Fax: (+81) 75-753-3970.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Fujimoto
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku Kyoto, 606-8502 (Japan), Fax: (+81) 75-753-3970. yori@kuchem.kyoto-u.ac.jp.|ACT-C (Japan) Science and Technology Agency, Sakyo-ku, Kyoto 606-8502 (Japan). yori@kuchem.kyoto-u.ac.jp.
authors.forename: Hideki
authors.initials: H
authors.lastname: Yorimitsu
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku Kyoto, 606-8502 (Japan), Fax: (+81) 75-753-3970. osuka@kuchem.kyoto-u.ac.jp.
authors.forename: Atsuhiro
authors.initials: A
authors.lastname: Osuka
mesh_terms: D018360:Crystallography, X-Ray; D008665:Metalloporphyrins / Q000737:chemistry*; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry; D012821:Silanes / Q000737:chemistry*
chemical_list: C000607396:1,2-dichlorodisilane; D008665:Metalloporphyrins; D011166:Porphyrins; D012821:Silanes; D009532:Nickel
keywords: lithiation; porphyrin; porphyrin dimer; silylation; substituent effects