Mueller, Matthias; Eversheim, Ellen; Englert, Ulli; Boese, Roland; Paetzold, Peter:

Protolysis of tri-tert-butylazadiboriridine: formation of a B-H-B bridge in unusual coordination.

In: Chemische Berichte (Chem.Ber.), Jg. 128 (1995) ; Nr. 2, S. 99-103
ISSN: 0009-2940
Zeitschriftenaufsatz / Fach: Chemie
The B-B bond of tri-tert-butylazadiboriridine (I) is oxidized by MeOH to give the (hydroboryl)(methoxyboryl)amine HBR:NRBR(OMe) (2a). m-2,3-Hydroazoniadiborata-1-cyclopropenes II (X = e.g., OSO2CF3, NHB10H12N3) are formed by the action of the acids HX upon I. A similar H bridge as in II is formed during the hydroboration of I by catecholborane. A B atom is identified in the hydroazoniadiborata-1-cyclopropene products to be planarly coordinated by four atoms, two of which are forming a BHB three-center bond with the B atom. This is a novel bonding situation in B chem. The structures of the products are deduced from 1H-, 11B-, and 13C-NMR spectra and are confirmed by x-ray structural analyses of 2a and II (same X as above).