On the Reduction of <i>S</i>-Alkyl-thionocarbonates (Xanthates) with Phosphorus Compounds
作者:Jean Boivin、Rafik Jrad、Stéphanie Juge、Van Tai Nguyen
DOI:10.1021/ol0342610
日期:2003.5.1
[reaction: see text] Reductive cleavage of the carbon-sulfur bond present in S-alkyl-thionocarbonates (xanthates) was achieved by high-yielding, tin-free radical reactions based on phosphorus reagents. The combination hypophosphorousacid/triethylamine/AIBN led to fast, efficient, and smooth formation of the alkane. Reduction with diethyl phosphite was sufficiently slow to permit sequential intermolecular
An Expedient, Flexible and Convergent Access to Selectively Protected 1,5-Dicarbonyl Compounds. Applications to the Synthesis of 2,6-Disubstituted Pyridines and Thiopyridines
作者:Jean Boivin、Floriane Carpentier、Rafik Jrad
DOI:10.1055/s-2006-926464
日期:2006.5
Intermolecular addition of 2-oxoalkyl radicals generated from the corresponding S-alkyl-O-ethyl dithiocarbonates on vinyl ketals afforded selectively protected 1.5-dicarbonyl compounds in good yields. These key-intermediates can be converted into a plethora of useful substances. Transformations to pyridines and thiopyridines were given as examples.