Diastereoselective Coupling of Anodically Generated Radicals Bearing Chiral Amide Groups

摘要

Anodic decarboxyiation of carboxyhe acids provides radicals (Kolbe electrolysis) and carbocations (non-Kolbe electrolysis) sflectively and directly for synthesis. The radicals may be used for homo- or hererocoupling reactions and for inter- or intramolecular additions to double bonds. The configurations of stereogerr.c centers at C3 or more distant positions of the car-boxylic acids are retained, while those at C2 are completely lost. By contrast, the use of chiral auxiliaries could lead to the formation of a stereogenic center at C2. Such induction has not yet been described lor Kolbe electrolysis, whilst some cases are known for non-Kolbe electrolyses. Recently dia.Uereoselectn e cyelizations by the coupling of photochemically generated radicals have also been described.