Patent ID: 6423859
Filing Date: 2002-07-23
Classification: C07F

Abstract:
Process for the preparation of organosilylalkylpolysulfanes of the general formula(R1R2 R3SiR4)2Sxâ€ƒâ€ƒ(I) in which the symbols denoteR1, R2, R3: which are identical or different from one another, branched and unbranched alkyl and/or alkoxy groups having a chain length of 1-8 C atoms, aryl radicals, at least one alkoxy group being present, R4 divalent alkylene radical having a chain length of 1-8 C atoms, or â€”(CH2)nâ€”C6H4â€”(CH2)nâ€” where n=1-4, x: number &gE;1, characterized in that organosilylalkylpolysulfanes of the general formula II (R1R2R3SiR4)2Syâ€ƒâ€ƒ(II) â€ƒin which R1, R2, R3 and R4 have the abovementioned meaning and y number >x, are reacted with an ionic sulfide of the general formula (III) M+2S2âˆ’â€ƒâ€ƒ(III) â€ƒin which M+ represents an alkali metal cation, an ammonium ion, half an alkaline earth metal cation or half a zinc cation, and an organosilylalkyl halide of the general formula R1R2R3SiR4Xâ€ƒâ€ƒ(IV) â€ƒin which R1, R2, R3 and R4 have the abovementioned meaning and X: is chlorine, bromine or iodine, the long-chain organosilylalkylpolysulfane of the general formula (II) and the organosilylalkyl halide of the general formula (IV) being initially introduced into the reaction vessel and the ionic sulfide of the general formula (III) being added to this solution in several portions.