Direct Catalytic Enantioselective Mannich Reactions: Synthesis of Protected <i>anti</i>-α,β-Diamino Acids
作者:Gary A. Cutting、Nikki E. Stainforth、Matthew P. John、Gabriele Kociok-Köhn、Michael C. Willis
DOI:10.1021/ja073473f
日期:2007.9.1
Anti-configured protected α,β-diamino acids are prepared with up to 99% ee using a direct catalytic enantioselective Mannich reaction. A catalyst system incorporating a chiral bis(oxazoline) ligand, Mg(ClO4)2 and Hunigs base, promotes the addition of an isothiocyanate-substituted imide to a variety of aryl-, heteroaryl-, alkenyl-, and alkyl-derived imines. Conversion of the products to their iPr-ester
使用直接催化对映选择性曼尼希反应制备了具有高达 99% ee 的反构型保护的 α,β-二氨基酸。包含手性双(恶唑啉)配体、Mg(ClO4)2 和 Hunigs 碱的催化剂体系促进了异硫氰酸酯取代的酰亚胺与各种芳基、杂芳基、烯基和烷基衍生的亚胺的加成。将产品转化为它们的 iPr 酯衍生物允许差向异构化为顺式非对映异构体。