作者:Pei-Hsun Wei、Ahmad A. Ibrahim、Mukulesh Mondal、Divya Nalla、Gero D. Harzmann、Frank A. Tedeschi、Kraig A. Wheeler、Nessan J. Kerrigan
DOI:10.1016/j.tetlet.2010.10.026
日期:2010.12
ketoketenes has been explored and compared with that of the previously reported trialkylphosphite-mediated reactions. NMR studies of the PBu3-catalyzed reaction implicated the involvement of tetravalent phosphonium intermediates. Phosphonium intermediates in the catalytic cycle were trapped through reaction with trimethylsilyl chloride and 4-chlorobenzaldehyde, and the resulting products were characterized
已经探索了PBu 3催化酮酮的均二聚的机理,并将其与先前报道的亚磷酸三烷基酯介导的反应进行了比较。PBu 3的NMR研究-催化的反应牵涉到四价involvement中间体的参与。通过与三甲基甲硅烷基氯和4-氯苯甲醛反应,捕集催化循环中的intermediate中间体,并对所得产物进行了表征。这些研究的结果是开发了一种化学计量生成烯醇化phospho的方法。与三烷基亚磷酸酯介导的二甲基乙烯酮均二聚机理相反,没有证据表明五价膦烷中间体参与三烷基膦催化的酮乙烯均二聚反应。甲基苯基烯酮二聚体的X射线晶体结构分析表明,其具有关于环外烯烃的Z-几何形状。