Organoceriumreagents, prepared from organolithiums and anhydrous cerium (III) chloride, react cleanly with easily enolizable ketones to afford the addition products in good to excellent yields.
Synthesis and reactivity of benzylic and allylic samarium compounds
作者:C. Bied、J. Collin、H.B. Kagan
DOI:10.1016/s0040-4020(01)88468-4
日期:1992.1
Benzyl and allyl samarium species are prepared by reaction of benzylic or allylicchlorides with SmCp2. They present a wide scope of reactivity towards aldehydes, ketones and acid chlorides.
The addition of Grignardreagents to ketones is significantly enhanced by cerium chloride with remarkable suppression of side reactions, particularly enolization. Some esters, which are prone to side reactions, also react readily with Grignardreagents in the presence of cerium chloride to give normal reaction products in reasonable to high yields.