Asymmetric Synthesis of α-Allyl-α-Aryl α-Amino Acids by Tandem Alkylation/π-Allylation of α-Iminoesters
作者:John M. Curto、Joshua S. Dickstein、Simon Berritt、Marisa C. Kozlowski
DOI:10.1021/ol500506t
日期:2014.4.4
The first asymmetric synthesis of α-allyl-α-aryl α-amino acids by means of a three-component coupling of α-iminoesters, Grignard reagents, and cinnamyl acetate is reported. Notably, the enolate from the tandem process provides a much higher level of reactivity and selectivity than the same enolate generated via direct deprotonation, presumably due to differences in the solvation/aggregation state.
报道了通过α-亚氨基酯、格氏试剂和乙酸肉桂酯的三组分偶联首次不对称合成α-烯丙基-α-芳基α-氨基酸。值得注意的是,与通过直接去质子化产生的相同烯醇化物相比,串联过程中的烯醇化物提供了更高水平的反应性和选择性,这可能是由于溶剂化/聚集状态的差异。一种去除高烯丙基胺保护基团的新方法可提供游离胺同系物。α-烯丙基提供了一种产生更多有价值的 α-氨基酸结构的方法,例如通过闭环复分解产生更高的 α-芳基-脯氨酸环同系物。