GENERATION OF BETA-CARBONYL RADICALS FROM CYCLOPROPANOL DERIVATIVES BY THE OXIDATION WITH MANGANESE(III) 2-PYRIDINECARBOXYLATE AND THEIR REACTIONS WITH ELECTRON-RICH AND ELECTRON-DEFICIENT OLEFINS

Various beta-carbonyl radicals are generated oxidatively from cyclopropanol derivatives by the use of manganese(III) 2-pyridinecarboxylate (Mn(pic)3). These beta-carbonyl radicals react with electron-rich olefins such as conjugated silyl enol ethers, a ketene thioacetal, a ketene dithioacetal, and a vinyl ether intermolecularly to give crossed-addition products in good yield. Furthermore, the combined use of Mn(PiC)3 and tributyl-hydridotin makes it possible to carry out the 1: 1 addition reaction of these beta-carbonyl radicals with electron-deficient olefins such as acrylonitrile, acrylaldehyde, methyl acrylate, methyl vinyl ketone, and N,N-dimethylacrylamide, and the corresponding products are obtained in moderate to good yield.