13C chemical shift non-equivalence in methylene carbons of monosubstituted cyclohexanes
作者:Hiroshi Ito、Alfred F. Renaldo、Robert D. Johnson、Mitsuru Ueda
DOI:10.1002/mrc.1260270315
日期:1989.3
Monosubstitutedcyclohexanes were synthesized by addition of a cyclohexyl radical to olefins bearing different substituents at the α‐position. Six distinct methylene 13C resonances were observed, indicating that the methylene carbons located at the 2 and 6 positions and at the 3 and 5 positions are not magnetically equivalent. This magnetic non‐equivalence (anisochronism) observed in the monosubstituted
A New Coupling Reaction of Alkyl Iodides with Electron Deficient Alkenes Using Nickel Boride (cat.)−Borohydride Exchange Resin in Methanol
作者:Tae Bo Sim、Jaesung Choi、Meyoung Ju Joung、Nung Min Yoon
DOI:10.1021/jo961751f
日期:1997.4.1
addition reaction of alkyliodides with alpha,beta-unsaturated esters, nitriles, and ketones proceeds in moderate to excellent yields (50-95%) using Ni(OAc)(2) (0.05-0.2 equiv)-BER (3-5 equiv) in methanol in 1-9 h at room temperature or at 65 degrees C. Nickel boride on borohydride exchange resin (BER) is a good alternative reagent to tributyltin hydride for the coupling of alkyliodides with the electron