Enantioselective addition of diethylzinc to aldehydes catalyzed by 5-cis-substituted proline derivatives
作者:Felix Prause、Stefan Wagner、Matthias Breuning
DOI:10.1016/j.tet.2018.11.030
日期:2019.1
5-Cis-substituted prolinols, prolinamines, and prolinamine sulfonamides proved to be efficient ligands for the enantioselective addition of diethylzinc to aldehydes, providing up to 99% ee. The sense of asymmetric induction can be controlled by the nature of the exocyclic functional group (CPh2OH vs. CH2NHR vs. CH2NHSO3R). The additional 5-cis substituent exerts a strong beneficial effect on the chirality
5-顺式取代的脯氨醇,脯氨酰胺和脯氨酰胺磺酰胺被证明是二乙基锌对醛对映选择性加成的有效配体,可提供高达99%的ee。不对称诱导的感觉可以通过环外官能团的性质来控制(CPh 2 OH对CH 2 NHR对CH 2 NHSO 3 R)。附加的5-顺式取代基对手性转移具有强大的有益作用,因为它使催化剂结构刚性化。反应的立体化学结果在各自的过渡态上进行了详细讨论。