用3当量的t -BuLi处理苄基2-卤代苯基醚会同时导致锂卤交换和在苄基亚甲基上的锂化。这些二价阴离子不进行维蒂希重排,并且可以被亲电试剂捕获。它们与羧酸酯的反应提供相应的2-芳基-3-羟基-2,3-二氢苯并[ b ]呋喃,为非对映异构体的混合物。随后的酸催化或介导的脱水使各种2-芳基-3-取代的苯并[ b ]呋喃具有中等至良好的总收率。
Di-<i>tert</i>-butylneopentylphosphine (DTBNpP): An Efficient Ligand in the Palladium-Catalyzed α-Arylation of Ketones
作者:Steven M. Raders、Jessica M. Jones、Jeffrey G. Semmes、Steven P. Kelley、Robin D. Rogers、Kevin H. Shaughnessy
DOI:10.1002/ejoc.201402474
日期:2014.11
palladium(II) acetate provide an efficient catalytic system for the α-arylation of ketones. Aryl bromides were coupled with ketones using 0.25–0.5 mol-% Pd(OAc)2/DTBNpP in toluene at 50 °C, whereas aryl chlorides required a higher catalyst loading (0.5–2.0 mol-%) and a higher temperature (80 °C). Coupling of 2-bromophenol with ketones using the Pd/DTBNpP system provides an efficient route for the synthesis
One-Pot Synthesis of Benzofurans via Palladium-Catalyzed Enolate Arylation with <i>o</i>-Bromophenols
作者:Christian Eidamshaus、Jason D. Burch
DOI:10.1021/ol801510n
日期:2008.10.2
A one-pot synthesis of benzofurans which utilizes a palladium-catalyzed enolate arylation is described. The process demonstrates broad substrate scope and provides differentially substituted benzofurans in moderate to excellent yields. The utility of the method is further demonstrated by the synthesis of the natural product eupomatenoid 6 in three steps.