A stereoselective tandem conjugate addition reaction with a chiral amine-derived nucleophile is reported in which the enolate intermediate is quenched with 1,2-dibromotetrachloroethane as a mild brominating reagent. X-ray analysis of a subsequent derivative was used to prove the configuration at each of the four newly formed stereocenters. The resulting α-bromoester underwent selective transesterification catalyzed by mild base to allow selective manipulation of the two ester groups of the product.

中文翻译：

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非对映选择性共轭加成/环化/溴化：一步即可进入四个立体中心

报道了与手性胺衍生的亲核试剂的立体选择性串联共轭加成反应，其中烯醇酸酯中间体用1，2-二溴四氯乙烷作为温和的溴化试剂淬灭。随后的导数的X射线分析被用来证明在四个新形成的立体中心的每一个处的构型。所得的α-溴酸酯经过弱碱催化选择性酯交换，以允许产物的两个酯基的选择性操作。