Park Jung-Woo, Chen Zhiwei, Dong Vy M
Department of Chemistry, University of California, Irvine , 4403 Natural Sciences 1, Irvine, California 92697, United States.
J Am Chem Soc. 2016 Mar 16;138(10):3310-3. doi: 10.1021/jacs.6b01445. Epub 2016 Mar 8.
We report a Rh-catalyzed enantioselective cycloisomerization of α,ω-heptadienes to afford cyclohexenes bearing quaternary carbon centers. Rhodium(I) and a new SDP ligand promote chemoselective formation of a cyclohex-3-enecarbaldehyde motif that is inaccessible by the Diels-Alder cycloaddition. Various α,α-bisallylaldehydes rearrange to generate six-membered rings by a mechanism triggered by aldehyde C-H bond activation. Mechanistic studies suggest a pathway involving regioselective carbometalation and endocyclic β-hydride elimination.
我们报道了一种铑催化的α,ω-庚二烯对映选择性环异构化反应,以得到带有季碳中心的环己烯。铑(I)和一种新型SDP配体促进了环己-3-烯甲醛基序的化学选择性形成,而这种基序是狄尔斯-阿尔德环加成反应无法实现的。各种α,α-双烯丙基醛通过醛C-H键活化引发的机制重排生成六元环。机理研究表明了一条涉及区域选择性碳金属化和环内β-氢消除的途径。