Synthesis and characterization of new azido(o-phenylenedioxy)-boranes and azidobicyclononylboranes

The boron azides azido(o-phenylenedioxy)borane, (1,2-C6H4O2)B(N-3) 1, and a zidobicyclononylborane, C16H28NB2(N-3) 3, have been prepared by the reactio n of the corresponding chloroborane with trimethylsilyl azide. Both reactio ns were also carried out in the presence of pyridine. The resulting donor-a cceptor complexes 1 . C5H5N 2 and 3 . C5H5N 5 and the boron azides (1, 3) h ave been characterized by analytical and spectroscopic methods. The molecul ar structures of 1, 3 and 5 have been confirmed by a single crystal X-ray d iffraction study. The formation of 3 has been observed by a low temperature B-11 NMR study and a probable mechanism is discussed.