Cateholates as σ‐ and π‐Donationg Ligands: The Synthesis and Structure of (Et₄N)₂[W(CO)₄(O₂C₆H₄)] and the “Sixteen Electron” Analogue Resulting from CO Dissociation

Alkoxo ligands with strong π-donor character stabilize coordinatively unsaturated organometallic compounds. This is confirmed by the two complexes 2 (each formally 16-electron species), which are in equilibrium with the starting materials 1. When R = tBu, 1 exists in the pure state only under a CO atmosphere, and 2 can even be characterized by X-ray crystallography. R = H, tBu.