On the mechanism of the disproportionation of chlorinated silanes under the influence of Lewis bases

In the present work the influence of Lewis bases on the reaction mechanism of the disproportionation of halodisilanes into silylenes and monosilanes i s studied. The reaction profile of the disproportionation reaction is compu ted in the absence as well as in the presence of Lewis bases such as NH3, P H3, and OPH3. Differences between the reaction mechanisms are discussed in terms of the barrier heights and the geometrical and electronic structures of the transition states and products. The relevance of possible pre-comple xes between the Lewis base and the disilane is discussed and competitive re actions are addressed.