Rhodium-catalyzed isomerization of 1,3-diene monoepoxides to α,β-unsaturated carbonyl compounds
作者:Susumo Sato、Isamu Matsuda、Yusuke Izumi
DOI:10.1016/0022-328x(89)85435-x
日期:1989.1
α,β-Unsaturated aldehydes and ketones are readily formed by the rhodium(I) catalyzed isomerization of 1,3-diene monoepoxides. When RhH(PPh3)4 is used as a catalyst, only (E)-α,β-unsaturated carbonyl compounds are obtained selectively. The initial 1,3-diene monoepoxides are prepared regiospecifically from α-trimethylsilyl ketones by a two step procedure, bromination and subsequent vinylative epoxidation
fragmentation of primaryalkoxylradicals is usually a minor process with respect to hydrogen abstraction and other competing reactions. However, when β-aminoalcohols were used as substrates, the scission proceeded in good to excellent yields and no side reactions were observed. The fragmentation can be coupled with an allylation or alkylation reaction, to give alkaloidanalogues and functionalized