to >99 % enantiomeric excess (ee) have been obtained by proline catalysis in excellent yields under experimentally simple solvent-free conditions. Efficient mixing of all the components is accomplished by applying a mechanochemical technique (ball milling). The catalysis is air and moisture tolerant and can be performed with non-purified starting materials. Even mixtures of solely solid compounds react
在实验简单的无溶剂条件下,通过脯
氨酸催化以优异的收率获得了对映体过量(ee)高达99%以上的抗醛醇产品。通过使用机械
化学技术(球磨)可以实现所有组分的有效混合。催化是耐空气和湿气的,并且可以用未纯化的起始原料进行。即使是纯固体化合物的混合物也会发生反应,通过部分均匀的(蜂蜜状)中间熔体产生(大部分为固体)产物。由于反应物比率几乎为1:1(避免普遍过量的酮),因此产物分离很容易导致高羟醛产物收率。