Beryllium(0) Complex Found

Beryllium(0) Complex Found

Author: ChemistryViews.org

Zero-valent main group compounds are difficult to stabilize and thus an interesting challenge for inorganic chemists. There are a number of stable low-valent p-block complexes with unusual reactivities, often similar to transition metal complexes. Neutral zero-valent s-block compounds, however, have been predicted by computational chemists, but have never been synthesized until now.

Holger Braunschweig, University of Würzburg, Germany, and colleagues have isolated the first zero-valent neutral beryllium complexes (example pictured), stabilized by cyclic (alkyl)(amino)carbene (CAAC) ligands. The team added a single ligand to BeCl2 in benzene solution to give (CAAC)BeCl2, and obtained the final product, [Be(CAAC)2], by reducing the beryllium with KC8 in the presence of a second equivalent of CAAC ligand.

The researchers characterized the compound using X-ray crystallography, 9Be NMR, 1H NMR, and UV-Vis spectroscopy. The complexes have very short beryllium-carbon bond lengths and linear beryllium coordination, which indicates strong multiple Be–C bonding. Density functional theory (DFT) calculations confirm this and indicate a strong three-centre two-electron π-bond across the C–Be–C unit, further stabilized through π-backdonation from beryllium to the ligands.


 

Leave a Reply

Your email address will not be published.