Tetrapropylammonium Perruthenate Catalyzed Glycol Cleavage to Carboxylic (Di)Acids
摘要:
A new method to accomplish glycol cleavage to carboxylic (di)acids in one step using catalytic amounts of tetrapropylammonium perruthenate (TPAP) together with N-methylmorpholine N-Oxide (NMO) as the stoichiometric oxidant is presented. In addition to regenerating the active catalyst, the N-oxide stabilizes intermediary carbonyl hydrates and thereby shifts a crucial equilibrium. The mild oxidation protocol is applicable to a broad range of substrates providing the respective acids, diacids, or keto acids in high yields.
Surfactants based on a newly discovered class of compounds include a hydrophobic lipid oligomer covalently linked to a peptide or peptide-like chain and a carbohydrate moiety, and a serine- leucinol dipeptide linked to the lipid oligomer. Such surfactants can be used to create an oil-in- water or water-in-oil emulsion by mixing together a polar component; a non-polar component; and the surfactant. Biosurfactants of the newly discovered class can be made by isolating and culturing a microorganism which produces the biosurfactant, and then isolating the biosurfactant from the culture. A microorganism can be engineered to produce biosurfactant of this newly discovered class by expressing a set of heterologous genes involved in the biosynthesis of the biosurfactant in the microorganism.