GB540907A - Process for the manufacture of ethers and esters of dl-tocols - Google Patents

Abstract

540,907. Tocol ethers and esters. HOFFMANN-LA ROCHE & CO., AKT.-GES., F. Feb. 1, 1940, No. 1984. Convention date. Feb. 14, 1939. [Class 2 (iii)] Ethers and esters of dl-tocols are prepared by condensing phytol or phytol halides with monoethers or mono-esters of dimethylhydroquinones having in free position ortho to the free hydroxyl group in the presence of an acidic condensing agent. The products are intermediates for the manufacture of therapeutic compounds exerting the activity of Vitamin E. Examples describe the condensation in the presence of zinc chloride of (1) 2:5-dimethylhydroquinone monobenzyl ether with phytyl bromide ; the resulting 5:8-dimethyltocol benzyl ether yields the therapeutically active 5:8-dimethyltocol on hydrogenation in the presence of palladiumcharcoal ; (2) 2:3-dimethylhydroquinone monobenzoate with phytyl bromide to give 7:8- dimethyltocol benzoate, which can be saponified to the active dl-7:8-dimethyltocol by means of methyl-alcoholic caustic potash ; (3) 2:5- dimethylhydroquinone monoacetate with phytyl bromide to produce 5-8-dimethyltocol acetate, which is active and can be saponified to 5:8-dimethyltocol; similarly, 5:8-dimethyltocol benzoate can be obtained by condensation of 2:5-dimethylhydroquinone monobenzoate with phytol. Specifications 532,364, 536,602, 544,027 and 573,719 are referred to. The Specification as open to inspection under Sect. 91 also describes the use of the mono-ethers and mono-esters of trimethylhydroquinone as starting materials. This subject-matter does not appear in the Specification as accepted.