coupling partners can be employed for the synthesis of conjugated dienes by palladium-catalyzed cross-coupling with tosylhydrazones: α,β-unsaturated ketone and aryl halide or alkenyl halide and non-conjugated tosylhydrazone. Depending on the substrate, a vinylogous hydride elimination is responsible for the formation of the final dienes.
Achieving Vinylic Selectivity in Mizoroki-Heck Reaction of Cyclic Olefins
作者:Xiaojin Wu、Yunpeng Lu、Hajime Hirao、Jianrong Steve Zhou
DOI:10.1002/chem.201204427
日期:2013.5.3
In Heck reactions of cyclicolefins, the products usually have aryl groups that end up at the allylic and/or homoallylic position. We herein report new selectivity that adds aryl groups to the vinylic position. Cyclicolefins of various ring size worked well. The desired isomers were produced by palladium–hydride‐catalyzed isomerization of the initial products. Thus, a specific catalyst must be used