TERT-BUTYL ISOCYANATE, A NONRIGID MOLECULE

The geometric structure of tert-butyl isocyanate, (CH3)(3)CNCO, was de termined by gas electron diffraction. The scattering intensities are f itted best with a non-rigid model which possesses a large-amplitude to rsional motion of the tert-butyl group around the N-C bond and an equi librium structure with staggered orientation of the tert-butyl group w ith respect to the N=C=O group. The nitrogen bond angle [C-N=C=137(2)d egrees] is equal to that estimated from rotational constants. It is ve ry similar to C-N=C angles in methyl and ethyl isocyanate and is not a ffected by steric interactions, (C) 1997 Elsevier Science B.V.