GB534490A - An improved process of forming ketones - Google Patents

Abstract

534,490. Ketones, alcohols. TRIGGS, W. W. (Du Pont de Nemours & Co., E. I.). Sept. 7, 1939, No. 25369. [Class 2 (iii)] Ketones are made by heating primarysecondary glycols, containing a chain of at least 8 carbon atoms and having at least two carbon atoms between the primary and secondary carbinol groups, to temperatures of above 150‹C. in contact with dehydrogenation catalysts, particularly metals of Group 8 of the Periodic system or their compounds, either in massive state or supported on a porous carrier such as kieselguhr or pumice. The parent materials may be obtained by catalytic hydrogenation of compounds such as castor oil or oiticica oil containing a hydroxy or ketonic group separated by at least two carbon atoms from a group capable of hydrogenation to a primary carbinol group. The resulting ketones contain one less carbon atom than the parent glycols, and may be hydrogenated to the corresponding alcohol. In examples : (1) technical octadecanediol-1:12 is heated with an active nickel catalyst ; the chief product is heptadecanone-7 ; (2) ricinoleyl alcohol, prepared by the sodium reduction of castor oil, is hydrogenated in the presence of a nickel catalyst in an autoclave, and the reaction vessel is then heated to 250‹C. ; heptodecanone-7 is obtained; (3) castor oil is hydrogenated in an autoclave in the presence of a copper chromate catalyst, a small sample of the product is removed, mixed with a nickel-on-kieselguhr catalyst and restored to the autoclave, and the reaction vessel is heated to 250‹C. ; heptadecanone-7 is obtained ; (4) octadecanediol-1:12 is heated in the presence of a palladium-on-charcoal catalyst ; heptadecanone-7 is obtained ; (5) octadecanediol-1:12 is heated with a nickel-onkieselguhr catalyst and is then hydrogenated to yield heptadecanol-7, and (6) castor oil is hydrogenated in the presence of a mixed copper chromate and nickel catalyst; heptadecanone-7 is first produced, and is then further hydrogenated to heptadecanol-7. Specification 318,124, [Class 2 (iii)], is referred to.