A Convenient Triisobutylaluminium (TIBAL)-Promoted Johnson-Claisen Approach to γ,δ-Unsaturated Alcohols
作者:Ross McGeary、Kelly Cosgrove
DOI:10.1055/s-0029-1217382
日期:2009.7
Mixed ortho esters derived from allylic alcohols undergo methanol elimination in the presence of triisobutylaluminium (TIBAL) at room temperature to form mixed ketene acetals. TIBAL then promotes immediate Claisen rearrangement of these intermediates, and subsequent reduction of the ester products, to give unsaturated γ,δ-primary alcohols in a convenient, one-pot procedure.
来自烯丙醇的混合正酯在室温下与三异丁基铝(TIBAL)反应时发生甲醇消除,形成混合酮烯醇。TIBAL随后促进这些中间体的克莱森重排,以及酯产物的后续还原,便捷地在一个反应瓶中生成不饱和γ,δ-初级醇。