STRUCTURE OF B-MONOAMINOBORAZINE

The molecular structure of B-monoaminoborazine in the gas phase has been investigated by electron diffraction. Molecular parameters were deduced from scattered intensity data obtained over the region 4 < q < 120 by a least-squares fitting procedure. Three models were considered: a planar ring, the borazine ring in a chair conformation, and the borazine ring in a boat conformation. For all models the amine N was assumed to be coplanar with the NBN group to which it is attached. The least-squares analysis converged in all cases when the mean-square amplitudes for N-H and B-H were constrained to reasonable values. The three models fitted the data equally well. The bonded distances were determined to be: B-N (ring) = 1.418 ± 0.004 Å B-N (amine) = 1.498 ± 0.008 Å B-H = 1.25 ± 0.03 Å N-H (ring) = 1.033 ± 0.02 Å N-H (amine) = 1.062 ± 0.03 Å. The departure from coplanarity of the heavy atoms in the average structure is small, but its magnitude cannot be determined from this experiment. It appears best to describe the molecule as being essentially planar, with the exception of the amine hydrogens. © 1969, American Chemical Society. All rights reserved.