Me2BN(SiMe3)(OSiMe3) thermolyzed, reaction mixt. dropped to PhCH2N3; byproducts removed in vac.; elem. anal.;

byproducts: (Me3Si)2O; under N2 heating at 70°C for 20 h; distn., products not sepd., identified by NMR, MS;

mixt. of Me2BN(SiMe3)(OSiMe3) and pentane thermolyzed at 400 K, products added to Bu3B; pentane, disiloxane, hexamethyldisiloxane and excess of Bu3B distd. off in vac.; elem. anal.;