Jd. Carpenter et Bs. Ault, MATRIX-ISOLATION STUDY OF THE REACTIONS OF B2H6 WITH PYRIDINE, PYRROLE, AND PYRROLIDINE - SPECTROSCOPIC CHARACTERIZATION OF C4H9N.BH3 AND C4H8N=BH2, Journal of physical chemistry, 97(44), 1993, pp. 11397-11401
The products of the pyrolytic reaction of B2H6 With pyrrole, pyrrolidi
ne, and pyridine have been isolated in argon matrices at 14 K and char
acterized by infrared spectroscopy. For the B2H6/C4H9N system, complex
formation was observed at temperatures between ambient and 200-degree
s-C and the subsequent H-2 elimination product H2B=NC4H8 at pyrolysis
temperatures above 50-degrees-C. The B=N stretching frequency (1486 cm
-1) and local density functional calculations done in support of the e
xperiments both support substantial double-bond character for the boro
n-nitrogen bond. The reaction of B2H6 with pyridine led to formation o
f the H3B.NC5H5 complex only, while copyrolysis of B2H6 with pyrrole l
ed to no reaction even when a pyrolysis temperature of 380-degrees-C w
as employed. This result is best understood in terms of the role of th
e nitrogen lone pair in the aromaticity of the pyrrole ring.