SOLID-STATE STRUCTURE OF SULFUR BIS(TRIMETHYLSILYLIMIDE), S(NSIME3)2, AND MULTINUCLEAR MAGNETIC-RESONANCE STUDIES OF SOME SULFUR BIS(SILYLIMIDES) IN SOLUTION

In the solid state sulfur bis(trimethylsilylimide) 1 has been shown to adopt the E/Z configuration by single-crystal X-ray diffraction (space group P1BAR, triclinic). In solution sulfur bis(silylimides) R (NSN) R' [R = R' = SiMe3 1 or Si2Me5 2; R = SiMe3, R' = Si2Me5 3 or SiMe2SiMe2(NSN)SiMe3 4] are fluxional at room temperature. Comparison of the H-1, C-13, Si-29 and, in particular, N-15 NMR data indicates that 1 and 2 undergo rapid E/Z half arrow right over half arrow left Z/E isomerization even at 173 K, whereas in the case of 3 and 4 this process is slowed at low temperature and the E/Z configuration prevails with the SiMe3 group in the E position.