example for the stabilization of memo 3 methacryloxypropyltrimethoxysilane compare german patent specification 3 832 621 the product thus obtained is distinguished by a particularly outstanding color number another aspect of the invention is the use of dppd purified by the process of the invention for the stabilization of organosilanes containing methacryloxy or acryloxy groups of the formula i str1 wherein r is a hydrogen atom or a methyl group r 1 and r 2 are identical or different alkyl groups having 1 to 4 c atoms or phenyl groups and m is equal to 0 1 or 2 the purified dppd of the invention can also be used in tire manufacture a further advantage of the process of the invention is that because of the use of largely non polluting hydrocarbons methods using chlorinated hydrocarbons as extractants do not have to be employed having generally described this invention a further understanding can be obtained by reference to certain specific examples which are provided herein for purposes of illustration only and are not intended to be limiting unless otherwise specified an extraction vessel fitted with a liquid permeable bottom is filled with 5 5 kg of silica gel 60 grain size 0 2 to 0 5 mm made by merck which is mixed with 4 kg of ceramic saddle type packing having a diameter of 15 mm above this adsorption layer a liquid permeable extraction vessel containing 10 kg of crude dppd made by gobel and pfrengle.