The tetrahedral character of the boron atom newly defined - a useful tool to evaluate the N -> B bond

The tetrahedral character at the boron atom in boron complexes with a coord inative N --> B bond has been evaluated on the basis of 144 solid state and gas phase molecular structures in order to obtain additional information o n the van der Waals versus covalent relationship of the boron-nitrogen bond . The tetrahedral character has been calculated by a new formula that inclu des all six bond angles at the boron atom. Thereby, the N --> B bond length and the tetrahedral character are correlated and permit the description of the reaction path for the formation of the N --> B bond. (C) 1999 Elsevier Science S.A. All rights reserved.