Selective and efficient generation of alkyl radicals from alkenes as well as their addition to unsaturated ketones and aldehydes is reported. The method is based on a simple one-pot procedure involving the hydroboration of the alkene with catecholborane, followed by treatment with a catalytic amount of oxygen in the presence of DMPU and a radical trap. Examples of cyclization and cascade reactions are reported.
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