Patent ID: 6194595
Filing Date: 2001-02-27
Classification: C07F

Abstract:
A process for preparing a mixture of organosilicon oligosulfanes containing a high proportion of disulfanes of the general formula:Z-Alk-S.sub.x -Alk-Z (I)wherein each Z, which may be the same or different, represents the group: ##STR3##wherein each R.sup.1, which may be the same or different, is a member selected from the group consisting of a linear or branched alkyl group having 1-6 carbon atoms, a cycloalkyl radical having 5-8 carbon atoms, a benzyl radical, and a phenyl radical, wherein said phenyl radical may be optionally substituted by methyl, ethyl or chlorine; andwherein each R.sup.2, which may be the same or different, is a member selected from the group consisting of an alkoxy group with a linear or branched carbon chain having 1-6 carbon atoms, a cycloalkoxy group having 5-8 carbon atoms, a phenoxy group, and a benzyloxy group,wherein each Alk, which may be the same or different, is a divalent, saturated linear or branched hydrocarbon radical having 1-10 carbon atoms, or the group ##STR4##wherein each n, which may be the same or different, is from 1 to 4, and wherein x is from 1.5 to 3.0,the process comprising:reacting a suspension of finely divided sodium with sulfur, in amounts corresponding to a stoichiometry of an Na.sub.2 S.sub.x product to be prepared, in a first inert organic solvent, at temperatures above 98.degree. C., under an inert gas, to thereby form the Na.sub.2 S.sub.x product;filtering the Na.sub.2 S.sub.x product;dissolving or suspending the Na.sub.2 S.sub.x product, partially or completely, in a second inert organic solvent;reacting the Na.sub.2 S.sub.x in the second organic solvent with a compound of general formula (II):Z-Alk-Hal (II),wherein Z and Alk are as defined above, and wherein Hal is a chlorine or bromine atom, to thereby fonn an organosulfane mixture; andisolating the organosulfane mixture.