作者:James A. Marshall、Patrick Eidam
DOI:10.1021/ol0363568
日期:2004.2.1
[reaction: see text] Additions of vinylic zinc bromide reagents to alpha-chiral aldehydes (R(1) = CH(2)OTBS, R(2) = Me; R(1) = Me, R(2) = OTBS) in the presence of lithiated (+)- or (-)-N-methylephedrine proceed with predominant reagent control to afford anti or syn adducts stereoselectively, except when the aldehydes possess an alkoxy substituent at the alpha- or beta-positions (R(1) = Me, R(2) = OBn;
[反应:请参见文本]将乙烯基溴化锌试剂添加到α-手性醛中(R(1)= CH(2)OTBS,R(2)= Me; R(1)= Me,R(2)= OTBS)在锂化(+)-或(-)-N-甲基麻黄碱的存在下,进行主要试剂控制以立体选择性地提供抗加成或顺加成,除非醛在α-或β-位置具有烷氧基取代基(R(1 )= Me,R(2)= OBn; R(1)= CH(2)OBn,R(2)= Me),在这种情况下,螯合控制的加合物占主导地位。