Abstract: Silicon-nitrogen compounds are prepared by the reaction of an olefinic amine such as allylamine with a polydiorganosiloxane such as 1,1,3,3-tetramethyldisiloxane, in the presence of a platinum-containing hydrosilation catalyst, preferably a specifically defined platinum complex of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane. Depending on the reaction conditions, the product may be any of several compounds including bis(aminoalkyl)polydiorganosiloxanes and alkenylaminodisiloxanes which are spontaneously converted to cyclic disiloxazanes. The cyclic disiloxazanes may in turn be converted by hydrolysis to bis(aminoalkyl)octaorganotetrasiloxanes.