o-(シリルメチル)ベンジルエステルとアルケンの[4+2]環化付加反応：高

第 24 回福岡シンポジウム Poster 発表要旨
o-(シリルメチル)ベンジルエステルとアルケンの[4+2]環化付加反応：
高活性パラジウム触媒の開発
An Improvement of Palladium Catalyst for the [4+2] Cycloaddition of
o-(Silylmethyl)benzyl Carbonate with Alkenes
金玉樹、石塚賢太郎、桑野良一（九大院理）
Previously, we reported that o-(silylmethyl)benzyl carbonate 1 works as an equivalent of
o-xylylenes in the presence of a palladium(0) complex bearing a chelating bisphosphine.1
The palladium complex catalyzed the reaction of 1 with alkenes to give the [4+2] cycloadducts
in good yields. Meanwhile, the oxidative addition of the benzylic C–O bond to a
palladium(0) species is allowed by using a bulky electron-rich monophosphine in place of the
bidentate bisphosphine.2 Herein, we will report that the monophosphine is also useful as the
spectator ligand for the palladium-catalyzed [4+2] cycloaddition of 1 with alkenes.
First, a broad range of monophosphine ligands were evaluated for the
[4+2] cycloaddition of 1 with crotonate 2. As a result of the evaluation,
some electron-rich triarylphosphine-ligated palladium complexes were
found to catalyze the cycloaddition, affording the desired tetralin 3 in good
yield. In particular, ligand 4 allowed the palladium complex to produce
the cycloadduct 3 in 84% yield with 2 mol% catalyst loading under the
optimized condition (eq. 1).
With the optimized catalyst, various alkenes reacted with 1 to give the corresponding
cycloadducts in good yields as shown in the following figure.
＜参考文献＞
1）Kuwano, R.; Shige, T. J. Am. Chem. Soc. 2007, 129, 3082.
2）Ueno, S.; Komiya, S.; Tanaka, T.; Kuwano, R. Org. Lett. 2012, 14, 338.
発表者紹介
氏名
金
玉樹（キン
ギョクキ）
所属
九大院理
学年
M2
研究室
分子触媒化学（桑野研）

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