Studies of aminoboranes. Part II. Pyrolysis of monoalkylamine-boranes: some aminoborane trimers (1,3,5-trialkylcyclotriborazanes) and dimers

Abstract

Trimeric aminoboranes (RNH·BH₂)₃, where R = Me, Et, Pr, Bu, and Bu^t, each of which occurs in two forms, have been prepared by pyrolyses of the corresponding amine-boranes RNH₂,BH₃. The dimeric aminoborane (Bu^tNH·BH₂)₂ was also obtained from pyrolysis of Bu^tNH₂,BH₃ and a similar dimer (PrⁱNH·BH₂)₂ was the only aminoborane which could be isolated from the pyrolysis of PrⁱNH₂,BH₃. Proton magnetic resonance spectra of the aminoborane trimers have been studied and the isomers have been assigned cis- and trans-configurations.