VERFAHREN ZUR HERSTELLUNG VON ORGANOSILANEN

Preparation of organosilanes (I), comprises reacting (halogenoorganyl)alkoxysilane (II) with aqueous alkaline hydrogen sulfide, sulfur and alkali-carbonate in alcohol, where the molar ratio of (halogenoorganyl)alkoxysilane to alkaline hydrogen sulfide is 1:0.4 to 1:0.75 and the molar ratio of alkali-carbonate to alkaline hydrogen sulfide is 1:0.5 to 1:1.5. Preparation of organosilanes of formula ([((R) 2)(R 1>-O)Si-R 2>)] 2-S m) (I), comprises reacting (halogenoorganyl)alkoxysilane of formula ([((R) 2)(R 1>-O)Si-R 2>)]-X) (II) with aqueous alkaline hydrogen sulfide, sulfur and alkali-carbonate in alcohol, where the molar ratio of (halogenoorganyl)alkoxysilane to alkaline hydrogen sulfide is 1:0.4 to 1:0.75 and the molar ratio of alkali-carbonate to alkaline hydrogen sulfide is 1:0.5 to 1:1.5. R : 1-8C alkyl, 1-8C alkenyl, 1-8C aryl, 1-8C aralkyl or OR 1>; R 1>H, 1-24C monovalent alkyl or alkenyl, aryl, aralkyl, alkyl ether (-(C(R 3>) 2) y 1>-O-R 4>) or alkyl polyether (-C(R 3>) 2O) y 2>-R 4> or -(C(R 3>) 2-C(R 3>) 2-O) y 2>-R 4>); y 1>1-20; y 2>2-20; R 3>H or alkyl; R 4>optionally saturated, aromatic or mixed aliphatic/aromatic monovalent 1-30C hydrocarbon; R 2>optionally saturated aliphatic, aromatic or mixed aliphatic/aromatic divalent 1-30C hydrocarbon, which is optionally substituted with F, Cl, Br, I, SH, NH 2 or NHR 1>; m : average sulfur chain length of 1.5-4.5; and X : Cl, Br, F or I.