Asymmetric Michael Additions of a Chiral Phosphite to Nitroalkenes and Knoevenagel Acceptors
作者:Dieter Enders、Livio Tedeschi、Dominik Förster
DOI:10.1055/s-2006-926437
日期:2006.5
The diastereoselective Michael addition of an enantiopure phosphite to nitroalkenes and α,β-unsaturated malonates is described. High asymmetric inductions were obtained using a readily available TADDOL auxiliary. Racemization-free cleavage of the auxiliary led to α-substituted β-nitro phosphonates and β-substituted β-phosphono malonates in good yields and high enantiomeric excesses, respectively. An
描述了对映体纯亚磷酸酯与硝基烯烃和 α,β-不饱和丙二酸酯的非对映选择性迈克尔加成。使用现成的 TADDOL 辅助剂获得了高度不对称的感应。助剂的无外消旋裂解分别导致 α-取代的 β-硝基膦酸盐和 β-取代的 β-膦酰基丙二酸盐分别以良好的收率和高对映体过量。还报道了将该方法扩展到合成具有两个新的相邻立体中心的 α,β-二取代 β-硝基膦酸盐。