Departamento de Química Orgánica, Facultad de Química, Universidade de Vigo, Lagoas-Marcosende s/n, 36310 Vigo, Spain.
Org Lett. 2009 Mar 5;11(5):1083-6. doi: 10.1021/ol8028687.
A new Pd-catalyzed tandem intramolecular oxypalladation/Heck-type coupling between 2-alkynylphenols and alkenes is reported, leading to 3-(1-alkenyl)benzofurans. Participating alkenes include those substituted with an electron-withdrawing group (ester, ketone, amide, nitrile, sulfone), as well as styrene. Remarkably, beta-substituted-alpha,beta-unsaturated carbonyl-type derivatives also participate effectively. The ready availability of substituted alkynylphenols, together with flexibility in the alkene choice, makes this simple strategy a versatile one for the synthesis of structurally diverse benzofuran derivatives.
报道了一种新的 Pd 催化的 2-炔基苯酚和烯烃之间的分子内氧钯化/Heck 型串联反应，生成 3-(1-烯基)苯并呋喃。参与的烯烃包括取代有吸电子基团（酯、酮、酰胺、腈、砜）的烯烃以及苯乙烯。值得注意的是，β取代的α,β-不饱和羰基型衍生物也能有效地参与反应。取代的炔基苯酚的易得性以及烯烃选择的灵活性，使得这种简单的策略成为合成结构多样的苯并呋喃衍生物的一种通用方法。
