Process for the preparation of 3-chloropropyl-silanes

Process for the preparation of a 3-chloropropylsilane from a hydrogensilane and allyl chloride at a temperature which is at least equal to the boiling point of the higher boiling point reactant, by subjecting the reactants to an addition reaction in the presence of a platinum-containing carrier material located above the reactant mixture, conducting the vapors of the reactant mixture to a condenser while bypassing the carrier material, and passing the condensate formed in the condenser through the carrier material by way of a sluice into the boiling reactant mixture, where the condensate formed in the condenser which flows over the carrier material contains a stoichiometric excess of allyl chloride, based on the hydrogen-silane reaction compound.