Carbocyclic construction by the [2,3]sigmatropic rearrangement of cyclic sulfonium ylides. a new entry for the stereoselective synthesis of substituted cyclohexanones
作者:Fusao Kido、Kazuo Yamaji、Subhash C. Sinha、Toshiya Abiko、Michiharu Kato
DOI:10.1016/0040-4020(95)00409-2
日期:1995.7
The rhodium(II)-catalyzed cyclization of acyclic α-diazo-β-keto esters 1c,d provided stereoselectively the highlysubstituted cyclohexanones 3c,d respectively, by the [2,3]sigmatropic rearrangement via stereocontrolled nine-membered allylsulfonium ylides 2c,d. Further elaboration of 3d toward the cyclohexanone 36 accomplished asymmetric formal syntheses of the representative elemanoids, 37 and 38.