Ho Chun-Yu, Ng Sze-Sze, Jamison Timothy F
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
J Am Chem Soc. 2006 Apr 26;128(16):5362-3. doi: 10.1021/ja061471+.
Described are several classes of unusual or unprecedented carbonyl-ene-type reactions, including those between alpha olefins and aromatic aldehydes. Catalyzed by nickel, these processes complement existing Lewis acid-catalyzed methods in several respects. Not only are monosubstituted alkenes, aromatic aldehydes, and tert-alkyl aldehydes effective substrates, but monosubstituted olefins also react faster than those that are more substituted, and large or electron-rich aldehydes are more effective than small or electron-poor ones. Conceptually, in the presence of a nickel-phosphine catalyst, the combination of off-the-shelf alkenes, silyl triflates, and triethylamine functions as a replacement for an allylmetal reagent.
本文描述了几类不同寻常或前所未有的羰基-烯反应，包括α-烯烃与芳醛之间的反应。这些反应由镍催化，在几个方面补充了现有的路易斯酸催化方法。不仅单取代烯烃、芳醛和叔烷基醛是有效的底物，而且单取代烯烃的反应速度比多取代烯烃更快，大的或富电子的醛比小的或贫电子的醛更有效。从概念上讲，在镍-膦催化剂存在下，现成的烯烃、三氟甲磺酸硅酯和三乙胺的组合可作为烯丙基金属试剂的替代品。
