Transformation of aromatic compounds utilizing ambiphilicity of silylene

2016 Fiscal Year Final Research Report

• Project/Area Number: 25708004
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Organic chemistry
• Research Institution: Tohoku University
• Principal Investigator: Ishida Shintaro 東北大学, 理学(系)研究科(研究院), 准教授 (90436080)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: シリレン / 脱芳香族化反応 / 環化付加反応 / ピリジン / ラジカル

Outline of Final Research Achievements

(1) Regioselective photochemical cycloadditions of silylene with azulene and guaiazulene gave bicyclic [4]dendralene and heptafulvene derivatives, respectively. A red-shifted absorption band of thus obtained [4]dendralene was observed, which is attributed to the orbital interactions between dendralene and a silacyclopropane moieties. (2) Thermal dearomative cycloaddition of silylene with pyridines to afford azasilepins was investigated. (3) We found a silanol-catalyzed formal C-H insertion of silylene with pyridine. This reaction proceeds via deprotonation of silanol by base-coordinated silylene. (4) Phosphenium cation and silylene are isolobal. Thus, we planned oxidation of phosphinyl radical to synthesize phosphenium cation for the dearomative cycloaddition. We obtained phosphaalkene-silver complex by the oxidation of phosphinyl radical with silver salts. We succeeded in the generation of dicoordinate antimony- and bismuth-centered radicals as persistent species.

Free Research Field

有機典型元素化学