GENERATION AND TRAPPING OF BIS(DIALKYLAMINO)SILYLENES - EXPERIMENTAL-EVIDENCE FOR BRIDGED STRUCTURE OF DIAMINOSILYLENE DIMERS

Reduction of dichlorobis(diisopropylamino)silane and dichlorobis(cis-2 ,6-dimethylpiperidino) silane by alkali metals gave the corresponding bis(diisopropylamino)silylene and bis(cis-2,6-dimethylpiperidino)silyl ene, respectively. These were successfully trapped by toluene and benz ene as well as by hydrosilane, olefin, and acetylene. As the first evi dence for the existence of the bridged-dimer of the diaminosilylenes, we have found scrambling of the amino-substituents on a silicon atom d uring the simultaneous generation of two different bis(dialkylamino)si lylenes in benzene. Diaminosilyenes generated thermally from the other new precursors designed here gave no evidence for the bridged dimer, due to the high temperature required for the generation.