The molecular iodine promoted cyclization of aldehydes and pyrazolin-5-ones was accomplished in water using tetrabutylammonium iodide as a phase transfer catalyst, affording a variety of substituted (R*,R*)-bis(spiropyrazolone)cyclopropanes in good to excellent yields (76–96%). This aqueous reaction exhibits very high chemoselectivity, and the products were obtained by simple Büchner filtration without chromatographic isolation procedure.

中文翻译：

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水相合成 (

使用四丁基碘化铵作为相转移催化剂，在水中完成分子碘促进醛和吡唑啉-5-酮的环化，得到多种取代的(R*)-双(螺吡唑酮)环丙烷，收率良好至优异 (76–96%)。该水相反应表现出非常高的化学选择性，产物通过简单的布氏过滤获得，无需色谱分离程序。R*,