Preparation, physical and spectroscopic properties of B-halogen and B-pseudohalogen Δ2-tetrazaborolines, and preparation of the diboron compound Me2N4BBN4Me2

Abstract

B-Halogen substituted Δ²-tetrazaborolines have been prepared by treating methylamine–boron trichloride with methyl azide in the presence of a tertiary amine and by bromination of 1,4-dimethyl-Δ²-tetrazaboroline with N-bromosuccinimide. Treatment of 5-chloro-1,4-dimethyl-Δ²-tetrazaboroline with silver pseudohalides yielded cyano-, thiocyano-, and selenocyano-derivatives, and with sodium amalgam gave the diboron compound Me₂N₄BBN₄Me₂. A detailed study of the i.r. and Raman spectra of the halogen and pseudohalogen derivatives was undertaken to determine the mode of bonding of the pseudohalogen substituents.