Replacement of HMPA in Samarium Diiodide Promoted Cyclizations and Reactions of Organolithium Compounds
作者:Mathias Berndt、Alexandra Hölemann、André Niermann、Christoph Bentz、Reinhold Zimmer、Hans-Ulrich Reissig
DOI:10.1002/ejoc.201101830
日期:2012.3
Tripyrrolidinophosphoric acid triamide (TPPA) can replace carcinogenic HMPA as a Lewis basic additive in many reactions involving samarium ketyls. In most cases, yields and selectivities of cyclizations of (het)aryl, alkenyl, and alkynyl ketones are similar. TPPA is also a good substitute of HMPA in the O-silylation of an ester enolate and in reactions oflithiated 1,3-dithiane. All these results clearly
Tripyrrolidinophosphoric acid triamide (TPPA) 可以在许多涉及钐羰基化合物的反应中替代致癌的 HMPA 作为路易斯碱性添加剂。在大多数情况下,(杂)芳基、烯基和炔基酮环化的产率和选择性是相似的。在酯烯醇化物的 O-甲硅烷基化和锂化 1,3-二噻烷的反应中,TPPA 也是 HMPA 的良好替代品。所有这些结果清楚地表明,在许多情况下可以避免使用 HMPA。