Aziridino alcohols as catalysts for the enantioselective addition of diethylzinc to aldehydes
作者:David Tanner、Hanne T. Kornø、David Guijarro、Pher G. Andersson
DOI:10.1016/s0040-4020(98)00875-8
日期:1998.11
The chiral aziridino alcohols 1 – 3 have been prepared either from amino acids (1a from serine; 1b – 1i and 3 from threonine; 2a – 2e from allo-threonine) or via asymmetric synthesis (1j, 1k, 1l and 2f from methyl cinnamate). These easily available ligands act as catalysts for the enantioselective addition of diethylzinc to benzaldehyde, with up to 90% stereoselectivity. The absolute configuration
手性氮丙啶基醇1 - 3已经从氨基酸制备或者(1A从丝氨酸; 1B - 1I和3从苏氨酸;图2a -图2e从同种异体-苏氨酸),或通过不对称合成(1J,1K,1L和2F从肉桂酸甲酯)。这些容易获得的配体充当二乙基锌向苯甲醛对映选择性加成的催化剂,立体选择性高达90%。醇产物的绝对构型取决于氮丙啶环的取代模式,并提出了不同的过渡态模型来解释所观察到的对映选择性的转换。C 2酒石酸制备了对称的叠氮基叠氮二醇4a – 4h,并且还以较高的化学产率催化有机锌加成反应,并且高达94%的具有醚侧链的ee C 2对称配体5a – 5c效率较低(最高为46%ee)。除醛9-11外,还测试了最有效的配体(4c),ee最高为97%。