d-Penicillamine and l-cysteine derived thiazolidine catalysts: an efficient approach to both enantiomers of secondary alcohols
作者:M. Elisa Silva Serra、Dora Costa、Dina Murtinho、Nélia C.T. Tavares、Teresa M.V.D. Pinho e Melo
DOI:10.1016/j.tet.2016.08.036
日期:2016.9
d-Penicillamine derived thiazolidine ligands were prepared in a two-step synthetic sequence and used in the enantioselective alkylation of a variety of aromatic aldehydes with diethylzinc at room temperature. Excellent ee, up to >99%, and nearly complete conversions were observed. Structurally analogous l-cysteine derived thiazolidine ligands were also synthesized and tested for comparative purposes
d-青霉胺衍生的噻唑烷配体以两步合成顺序制备,并在室温下用于各种芳香醛与二乙基锌的对映选择性烷基化。优秀的ee,高达> 99%,并且观察到几乎完全的转换。还合成了结构相似的1-半胱氨酸衍生的噻唑烷配体,并进行了比较试验,结果显示出很好的选择性,尽管选择性略低,最高可达89%。两种噻唑烷的组合使用构成合成(S)和(R)手性仲醇的对映异构体,从而引出了无数有用的具有相反绝对构型的旋光产物。