Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
J Org Chem. 2010 Mar 5;75(5):1701-5. doi: 10.1021/jo902678p.
A complex of commercial Ir(OMe)(cod) and 4,4-di-tert-butyl-2,2-bipyridine (dtbpy) catalyzes the Z-selective, dehydrative silylation of terminal alkenes, but not 1,2-disubstituted alkenes, with triethylsilane or benzyldimethylsilane in THF at 40 degrees C. Yields and Z-stereoselectivity were significantly improved by 2-norbornene, in contrast with other sacrificial alkenes. The reaction is compatible with many functional groups including epoxides, ketones, amides, alcohols, esters, halides, ketals, and silanes. alpha,beta-Unsaturated esters were unreactive. The reaction probably proceeds through a Heck-type mechanism.
一种由商业[Ir(OMe)(cod)](2)和 4,4-二-叔丁基-2,2-联吡啶(dtbpy)组成的复合物在四氢呋喃中、40 摄氏度下,催化末端烯烃的 Z-选择性、脱水甲硅烷基化,但是不能催化 1,2-二取代烯烃的反应,三乙硅烷或苄基二甲基硅烷可以作为甲硅烷基供体。相比其他牺牲性烯烃,2-降冰片烯能显著提高产率和 Z-立体选择性。该反应能与许多官能团兼容,包括环氧化物、酮、酰胺、醇、酯、卤化物、缩醛和硅烷。α,β-不饱和酯则没有反应活性。该反应可能通过 Heck 型机理进行。