compounds in an enantiomerically pure form. Esters of propiolic acid and chiral alcohols were evaluated as cheap and readily available Michael acceptors in a diastereoselective synthesis of N‐stereogenic compounds by means of a double aza‐Michael conjugate addition. Diastereomeric ratios of up to 74:26 and high yields were achieved with (−)‐menthyl propiolate as a substrate. Furthermore, a detailed
缺乏结构对映体纯形式的有效策略阻碍了具有构型稳定的立体氮原子的手性化合物的
化学和应用的进一步发展。在N-立体异构化合物的非对映选择性合成中,通过双氮杂-Michael共轭加成,将
丙酸和手性醇的酯评估为便宜且容易获得的Michael受体。以(-)-
丙酸丙酯为底物可实现高达74:26的非对映异构体比例和高收率。此外,进行了详细的机械研究以阐明这种多米诺骨牌转化的过程。动力学研究表明,质子溶剂添加剂起布朗斯台德酸的作用,并在四氢重氮化合物伴侣的初次攻击下活化了酯。相反,在提供产物的最后环化步骤中,酸性条件被证明是不利的。