GB1449716A - Oxidation of olefinic compounds to glycols - Google Patents

Abstract

1449716 Oxidation of olefinic compounds to glycols FMC CORP 9 Aug 1974 35286/74 Heading C2C Olefinic compounds are oxidized in aqueous medium at a pH of at least 7 in the presence of osmium tetroxide with an alkali metal (e.g. Na) or alkaline earth metal hypochlorite at - 10‹ to + 60‹ C. to form a hydroxylated product containing two or more hydroxy groups, of which two are on adjacent carbon atoms, or a compound hydrolysable thereto. A co-solvent, e.g. diethyl ether or t-butanol, and a blending agent, e.g. an alkali metal salt of toluenesulphonic or xylenesulphonic acid, may be present. The osmium tetroxide concentration is preferably 10<SP>-5</SP>-10<SP>-3</SP> molar. The olefinic compound may be a monoene, diene or polyene and may have substituents, e.g. aryl, hydroxyl, halogen, cyano, carbonyl, carboxyl, carboxylic ester or amide; it may be an unsaturated heterocyclic compound, e.g. 2,4-dimethyl-5,6-dihydropyran; in the examples it is propylene, octene-1, hexadecene-1, c.hexene, c.octene, allyl alcohol, allyl chloride, acrylamide, acrylic acid and methyl acrylate, and the corresponding compounds with two hydroxy] groups added across the double bond are obtained. With allyl alcohol in t-butanol, some of the chlorohydrin, t-C 4 H 9 -O-CH(CH 3 )-CH 2 -Cl is present in the product, and hydrolysis of this with NaOH increases the yield of glycerol. The polyhydric alcohol product may be recovered by adding a slight excess of olefin to reduce osmium tetroxide to osmium dioxide, and distilling off water, and solvent followed by polyhydroxy compound, leaving sodium chloride and osmium dioxide; the latter may be reoxidized, e.g. with sodium hypochlorite, and recycled.