Greener Oxidation of Alcohols, Glycosides and Sulfides
Catalytic reactions significantly contribute towards the development of sustainable chemistry approaches that do not harm the environment. We have been actively developing novel catalytic reactions including enzyme catalyzed polymerization and green oxidation reactions. While chromium reagents have proven to be powerful and versatile oxidizing agents, their carcinogenicity makes them less attractive for any large scale or industrial applications. We have developed greener reactions for preparation of aldehydes, ketones, and carboxylic acids directly from alcohols. Our method is also useful for selective oxidative ring-opening of glycosides and for oxidation of sulfides to sulfones. In these reactions, we use pyridinium chlorochromate (PCC) as a catalyst together with a co-oxidant that is used to regenerate the catalyst. As a co-oxidant, we show that the electrolytically recyclable periodic acid works very well. Hence, using PCC as a catalyst, instead of a stoichiometric amount, we are able to reduce the amount of chromium waste generated by up to a 100 fold while still maintaining the power and versatility of chromium oxidation reactions.
Hunsen, Mo. “Greener oxidation of alcohols, glycosides and sulfides,” in "Green Technologies for the Environment," ACS Symposium Series, 6, 1117-128.
ACS Symposium Series