Preparation, spectroscopic characterization, and deprotonation reactions of Si(NHR)4 (R=i-Pr, t-Bu, p-tolyl) — EPR identification of persistent radicals formed by oxidation of polyimidosilicates

Treatment of Cl 2 Si(NH-t-Bu) 2 (6a) with t-BuNH 2 in boiling toluene yields trisamino(chloro)silane ClSi(NH-t-Bu) 3 (7); formation of the tetraaminosilane Si(NH-t-Bu) 4 is not observed. The reaction of SiCl 4 with 4 equiv. of LiNHR produces the corresponding tetraaminosilanes Si(NHR) 4 (2a, R = i-Pr; 2b, R = t-Bu; 2c, R = p-tol) in good yields. When the sterically demanding adamantyl derivative LiHNAd is employed, only disubstitution occurs to …