Structure of O-methyl-N,N-bis(trifluoromethyl)hydroxylamine, (CF3)(2)NOCH3

The molecular structure of (CF3)(2)NOCH3 was determined by gas electron diffraction. The molecular intensities were reproduced by use of a single conformation with syn orientation of the O-CH3 group relative to the nitrogen lone pair. This was confirmed by ab initio calculations (HF/3-21G(*), polarization functions only on nitrogen, and MP2/6-31G*). The observed structure demonstrates that the generalized anomeric effect is of minor importance to this compound. The following skeletal geometric parameters (bond lengths [pm] and angles [degrees] with 3-sigma uncertainties) were derived: N-C 142.9(7), N-O 142(3), O-C 145(3), CNC 118.0(9), CNO 108.1(17), and NOC 109.4(17). The experimental structure is well reproduced by the ab initio calculations.