Marshall JA, Chobanian HR
Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, USA.
J Org Chem. 2000 Dec 1;65(24):8357-60. doi: 10.1021/jo005658+.
Allenylzinc and indium reagents were generated in situ through Pd(0)-catalyzed metalation of (R)- and (S)-3-butyn-2-ol methanesulfonate with Et(2)Zn and InI. These reagents add to the benzyl and TBS ethers of (S)-lactic aldehyde to afford diastereomeric stereotriads in moderate to high yield. The (S)/(S) combination afforded the anti,anti adducts with 94:6-100:0 diastereoselectivity. The (R)/(S) combination was mismatched, affording a mixture of anti,syn and syn,anti adducts in diastereomeric ratios of ca. 80:20-85:15. Addition of the racemic allenylmetal reagents to the (S)-lactic aldehyde ethers afforded the products of matched and mismatched pairings in equal amount.
通过用Et(2)Zn和InI对(R)-和(S)-3-丁炔-2-醇甲磺酸酯进行Pd(0)催化的金属化反应，原位生成烯丙基锌和铟试剂。这些试剂加成到(S)-乳酸醛的苄基和TBS醚上，以中等至高收率得到非对映异构的立体三联体。(S)/(S)组合以94:6 - 100:0的非对映选择性得到反式、反式加合物。(R)/(S)组合不匹配，得到非对映体比例约为80:20 - 85:15的反式、顺式和顺式、反式加合物的混合物。将外消旋烯丙基金属试剂加成到(S)-乳酸醛醚上，得到等量的匹配和不匹配配对产物。
