Heteroaromatic-anchored enynals with a pendent alkene group were successfully cyclized through a Huisgen-type [3+2] cycloaddition to give a tetracyclic Pt–carbene complex that underwent insertion into the C–H bond in the β-position to give fused cyclopropanes that are otherwise inaccessible. On heating, the cyclopropanes smoothly rearranged to form the corresponding heterospiranes with excellent levels of stereoselectivity and high yields.

中文翻译：

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铂-卡宾插入反应中的环丙烷中间体：合成异螺烷的途径

通过Huisgen型[3+2]环加成成功环化带有悬垂烯烃基团的杂芳族锚定烯醛，得到四环Pt-卡宾配合物，该配合物插入β位的C-H键，得到稠合的环丙烷否则无法访问。在加热时，环丙烷平稳地重排形成相应的杂螺烷，具有优异的立体选择性和高产率。