Michael Addition−Elimination Mechanism for Nucleophilic Substitution Reaction of Cycloalkenyl Iodonium Salts and Selectivity of 1,2-Hydrogen Shift in Cycloalkylidene Intermediate
of allylic and vinylic forms. Deuterium-labeling experiments show that the allylic product is formed via the Michael addition of cyanide to the vinylic iodonium salt, followed by elimination of the iodonio group and 1,2-hydrogen shift in the 2-cyanocycloalkylidene intermediate. The hydrogen shift preferentially occurs from the methylene rather than the methine β-position of the carbene, and the selectivity
Michael Addition of Cyanide to Cyclohex-1-enyliodonium Salts
作者:Morifumi Fujita、Wan Hyeok Kim、Tadashi Okuyama
DOI:10.1246/cl.2003.382
日期:2003.4
Reaction of 4-substituted cyclohex-1-enyliodonium salt with cyanide in chloroform produces three isomeric cyanocyclohexenes, ipso and two cine products. Deuterium labeling experiments showed that the allylic cine product is formed via the Michael addition of cyanide, followed by elimination of the iodonio group and a 1,2-H shift.