Spin-spin coupling constants 1J(15N,11B) in boron-nitrogen compounds. Experimental data and DFT calculations

Abstract

Boron-nitrogen compounds were studied with respect to indirect nuclear (15N-11B) spin-spin coupling (1J( 15N,11B)). Some new experimental data were determined for aminoboranes and tetra-N-pyrrolylborate, and a variety of compounds with B-N single, double and triple bonds were examined using DFT methods for the calculation of 1J(15N,11B) at the B3LYP/6-311+G(d,p) level of theory. The calculations predict magnitude and sign of 1J(15N,11B) reasonably well, and the Fermi contact term was found to be dominant. A positive sign of 1J( 15N,11B) was calculated in the case of 1-aza-closo-dodecaborane(12), in contrast to all other compounds studied. © 2007 Verlag der Zeitschrift für Naturforschung.