GB938627A - Production of dithio fatty acid derivatives and intermediates thereof - Google Patents

Abstract

Compounds of the general formula <FORM:0938627/IV(a)/1> (wherein R is a carboxyl, carbalkoxy or carboxyamide radical and n is an integer of at most 7) are prepared by reacting compounds of the formula <FORM:0938627/IV(a)/2> with an organic sulphonyl halide in an alkaline medium, and if desired, hydrolysing the group R when carbalkoxy or carboxyamide to produce the free acids. Compounds (V) may be in turn prepared by treating compounds of the formulae <FORM:0938627/IV(a)/3> (wherein Y is an alkyloxy, alkylthio, arylthio, aralkylthio, acyloxy or acylthio radical and Y is a similar radical or a rhoden radical or, when n is 4 and R is carbomethoxy, it may be the radical -S-CH=CH-CO-(CH2)4-COOCH3) with hydrogen and hydrogen sulphide in the presence of a metal sulphide catalyst at an elevated pressure. Compounds (III) may be prepared by reacting compounds (II) with an appropriate alkanol, thioalkanol, fatty acid, thiofatty acid or a functional derivative thereof or an aryl or aralkyl thioalcohol in an alkaline medium. Compounds (IV) wherein Y1 is a rhoden radical or the radical -S-CH=CH-CO-(CH2)4-COOCH3 may be prepared from compounds (II) and an alkali thiocyanate, an alkali mono- or poly-sulphide or an alkali thiosulphate, or if Y1 is an alkoxy, alkylthio, arylthio, aralkylthio, acyloxy or acylthio radical they may be prepared from compounds (III), by treatment with a small amount of an acid, a base, a metal or a silicon compound. Free acids (V) may be esterified. Intermediate in the preparation of compounds (VIII) are compounds of the formulae <FORM:0938627/IV(a)/4> (wherein R1 is an alkyl, aryl or aralkyl radical). Detailed examples are provided. Specification 938,628 is referred to.