Diastereoselective electrophilic α-amination of camphor N1-acyl N2-phenylpyrazolidinones: the metal enolate-dependent synthesis of two possible hydrazide diastereomers
作者:Chin-Sheng Chao、Chung-Kai Cheng、Ssu-Hsien Li、Kwunmin Chen
DOI:10.1016/j.tetlet.2008.11.003
日期:2009.1
Complementary approaches under enolate amination reactions for the synthesis of both α-hydrazidoacyl diastereomers have been achieved. Both isomers are obtained with high to excellent chemical yields and high stereoselectivities (up to >95:5 dr) when aryl-substituted camphor N1-acyl N2-phenylpyrazolidinone was treated with potassium hexamethyldisilylamide (KHMDS) and lithium hexamethyldisilylamide
已经实现了在烯醇化胺反应下用于合成两种α-肼基酰基非对映异构体的补充方法。使用六甲基二甲硅烷基氨基钾(KHMDS)和六甲基二甲硅烷基锂(LHMDS)处理芳基取代的樟脑N 1-酰基N 2-苯基吡唑烷二酮时,两种异构体均具有很高的化学产率和很高的立体选择性(高达> 95:5 dr ),分别加入偶氮二羧酸二叔丁酯。可以在温和条件下进行的无损手性助剂的除去,提供了具有高对映体比率的酰肼醇。讨论了反应的面部立体选择性和立体化学过程。