Anionic ruthenium iodocarbonyl complexes as selective dehydroxylation catalysts in aqueous solution

Article abstract of DOI:10.1016/0022-328X(91)80159-H

The selective dehydroxylation in aqueous solution of C3-C5 polyols and C6 sugars in the presence of homogeneous ruthenium iodocarbonyl catalysts, ^- species, has been studied.Glycerol, pure or in dilute aqueous solution, is dehydroxylated to give n-propanol and its ethers with selectivities of up to 90percent.Xylitol and C6 sugars, glucose and fructose, are dehydrated and hydrogenated through initial formation of levulinic acid to give γ-valerolactone with high yields.The dehydroxylation of these polyhydroxylic substrates is made possible in water solution bythe bifunctional nature (acidity and hydrogenating ability) of the ruthenium catalystic system.The requirements necessary for the catalytic system to be active and stable in water have been studied, and the mechanism of the reaction discussed.