The diborane–methyl cyanide reaction. Further studies on volatile products

Abstract

Diborane and methyl cyanide at 80–90° give as volatile products NN′N″-triethylborazine Et₃N₃B₃H₃(35–40% yield), µ-diethylaminodiborane Et₂NB₂H₅(ca. 1% yield), and materials of higher molecular weight (15–20% yield) which may include compounds of formulae Et₅N₅B₄H₂, Et₄N₅B₅H₄, and Et₅N₆B₆H₅. Aspects of the i.r. and ¹H and ¹¹B n.m.r. and mass spectra of the products are discussed, and possible structures for the materials of higher molecular weight are indicated. Spectroscopic details are also given for µ-ethylaminodiborane EtNHB₂H₅, prepared from EtNH₂ and B₂H₆.