Department of Chemistry, Stanford University, Stanford, California 94305-5080, United States.
J Am Chem Soc. 2011 Feb 16;133(6):1706-9. doi: 10.1021/ja110501v. Epub 2011 Jan 18.
We report herein a new process, which we call contemporaneous dual catalysis, that selectively couples two highly reactive catalytic intermediates while overcoming competing trapping by stoichiometric reactive species also present in the reaction. The reaction proceeds via the convergence of a vanadium-catalyzed propargylic rearrangement and a palladium-catalyzed allylic alkylation. It generates a variety of α-allylated α,β-unsaturated ketones, which are not readily accessible by other means. Notably, this dual catalysis is achieved using low catalyst loadings (1.0 mol % [Pd], 1.5 mol % [V]) and gives good to excellent yields (up to 98%) of the desired products.
我们在此报告一种新的反应过程,我们称之为同时双催化,它可以选择性地偶联两个高反应性的催化中间体,同时克服反应中存在的化学计量的反应性物种的竞争捕获。该反应通过钒催化的丙炔基重排和钯催化的烯丙基烷基化的收敛进行。它生成了各种不易通过其他方法获得的α-烯丙基-α,β-不饱和酮。值得注意的是,这种双催化仅使用低催化剂负载量(1.0 mol % [Pd],1.5 mol % [V])即可实现,并且目标产物的收率良好至优异(高达 98%)。