s-Block Multiple Bonds: Isolation of a Beryllium Imido Complex

A common feature of d- and p-block elements is that they participate in multiple bonding. In contrast, the synthesis of compounds containing homo- or hetero-nuclear multiple bonds involving s-block elements is extremely rare. Herein, we report the synthesis, molecular structure, and computational analysis of a beryllium imido (Be=N) complex (2), which was prepared via oxidation of a molecular Be-0 precursor (1) with trimethylsilyl azide Me3SiN3 (TMS-N-3). Notably, compound 2 features the shortest known Be=N bond (1.464 angstrom) to date. This represents the first compound with an s-block metal-nitrogen multiple bond. All compounds were characterized experimentally with multi-nuclear NMR spectroscopy (H-1, C-13, Be-9) and single-crystal X-ray diffraction studies. The bonding situation was analyzed with density functional theory (DFT) calculations, which supports the existence of pi-bonding between beryllium and nitrogen.

Automated summary

A novel beryllium imido complex with the shortest Be=N bond reported to date was synthesized and characterized experimentally and computationally. The existence of pi-bonding between beryllium and nitrogen was supported by density functional theory calculations.