Non-destructive Removal of the Bornanesultam Auxiliary in ?-SubstitutedN-Acylbornane-10,2-sultanis under Mild Conditions: An efficient synthesis of enantiomerically pure ketones and aldehydes
作者:Wolfgang Oppolzer、Christophe Darcel、Patrick Rochet、Stephane Rosset、Jef De Brabander
DOI:10.1002/hlca.19970800502
日期:1997.8.11
two-step procedure involving a known mercaptolysis reaction followed by an [Fe(acac)3]-mediated coupling of the resulting S-benzyl thioesters with Grignard reagents. Furthermore, enantiomerically pure aldehydes 23 can be obtained from α-substituted N-acylbornane-10,2-sultams 6via a one-step reduction with (i-Bu)2AIH. No epimerization at the α-chiral center is observed during the cleavage reaction whereby
α-替补Ñ -acylbornane-10,2 -sultams 6,9,和10可以被转换成纯对映异构体酮5. 13,和14,分别经由涉及已知mercaptolysis反应,随后通过的[Fe两步过程(acac)3 ]-介导的所得S-苄基硫酯与格氏试剂的偶联。此外,对映体纯的醛23可以通过(i-Bu)2的一步还原从α-取代的N-酰基冰片烷-10,2-杜鹃花6获得。AIH。在切割反应过程中未观察到在α-手性中心的差向异构体,由此回收了手性助剂,硼烷-10,2-sultam 1或ent - 1。通过使用这种方法,可以制备几种天然产物或其前体。