Photochemical reactions. 148th communication. Photochemistry of acylsilanes: Preparation, photolyses, and thermolyses of ?,?-unsaturated silyl ketones
作者:Markus E. Scheller、Genji Iwasaki、Bruno Frei
DOI:10.1002/hlca.19860690612
日期:1986.9.10
the acylsilanes (E/Z)-7 undergo photoisomerization by δ-H abstraction furnishing the acylsilanes 29A + B. Flash vacuum thermolyses (FVT) of (E/Z)-7, (E/Z)-8, and (E)-9 give rise to intramolecular reactions of the siloxycarbene intermediates. Thus, FVT (520°) of (E)- and (Z)-7 selectively leads to the enol silyl ethers 32 and (E)-33, respectively, arising from carbene insertion into an allylic C–-H bond
描述了α,β-不饱和甲硅烷基酮(E / Z)-7,(E)-8和(E)-9的合成,光解和热解。在n,π*激发(λ> 347 mm)时,上述化合物经历(E / Z)异构化,然后进行γ-H提取。中间烯醇由siloxycarbenes导致二聚缩醛分子间被困27A + B,30A + B,以及31A + B。此外,酰基硅烷(E / Z)-7通过δ-H提取进行光异构化,从而提供了酰基硅烷29A + B。(E / Z)-7,(E / Z)-8和(E)-9的快速真空热解(FVT)引起甲硅烷氧基卡宾中间体的分子内反应。因此,(E)-和(Z)-7的FVT(520°)选择性地导致烯基甲硅烷基C-H键插入烯醇甲硅烷基醚32和(E)-33。(E / Z)-8(560°)和(E)-9的FVT(600°)得到三烯酚甲硅烷基醚34A + B和环状甲硅烷基醚37A + B,它们是通过CH插入甲硅烷氧基碳烯而形成的。作为(E