Acyclic asymmetric quaternary stereocenters, which are composed of four carbon-carbon bonds, were finely constructed by utilizing a face-selective alkylation of enolate intermediates derived from an asymmetric Michael addition reaction of a chiral lithium amide with trisubstituted (E)-α,β-unsaturated esters. The present face-selective alkylation was able to employ diverse alkyl halides as an electrophile to afford various Michael adducts having an all-carbon quaternary stereocenter. With regard to the deprotection of the chiral auxiliary, N-iodosuccinimide used in our previous study did not work in the present cases; however, we found that pyridine iodine monochloride in the presence of H₂O was effective to remove the bornyl group and the benzyl group on the amino group to provide the β-amino ester derivative.

无环的不对称季立体，其由四个碳-碳键，微细地通过利用从手性氨基化锂与三取代（的不对称迈克尔加成反应得到的烯醇化物中间体的面朝选择性烷基化构建ë）-α，β-不饱和酯。目前的面选择性烷基化能够使用不同的卤代烷作为亲电子试剂，以提供具有全碳四元立体中心的各种迈克尔加合物。关于手性助剂的脱保护，我们之前研究中使用的N-碘代琥珀酰亚胺在目前的情况下不起作用；然而，我们发现在 H ₂存在下，一氯化吡啶碘O可有效去除氨基上的冰片基和苄基以提供β-氨基酯衍生物。