A Three‐Dimensional Inorganic Analogue of 9,10‐Diazido‐9,10‐Diboraanthracene: A Lewis Superacidic Azido Borane with Reactivity and Stability

Abstract

Herein, we report the facile synthesis of a three-dimensional (3D) inorganic analogue of 9,10diazido-9,10-dihydrodiboraantracene, which turned out to be a monomer in both the solid and solution state, and thermally stable up to 230 °C, representing a rare example of azido borane with boosted Lewis acidity and stability in one. Apart from the classical acid-base and Staudinger reactions, EÀ H bond activation (E = B, Si, Ge) was investigated. While the reaction with BÀ H (9borabicyclo[3.3.1]nonane) led directly to the 1,1-addition on N α upon N 2 elimination, the SiÀ H (Et 3 SiH, PhMe 2 SiH) activation proceeded stepwise via 1,2-addition, with the key intermediates 5 int and 6 int being isolated and characterized. In contrast, the cooperative GeÀ H was reversible and stayed at the 1,2-addition step.