| Abstract: | 1H NMR spectra of substituted cyclotrisilazanes are discussed in terms of conformational analysis. Experimental spectra are consistent with an equilibrium involving chair conformers, following from simulating the effect of phenyl substituents and the temperature dependence of methyl proton chemical shifts. The barrier to chair-chair interconversion in hexamethyl-cyclotrisilazane is estimated. An analysis is carried out of the shielding of non-equivalent methyl groups in substituted cyclotrisilazanes. |
