Steric Control between Neutral Metal-Only Lewis Pairs and Metal-Stabilized Gallenium and Gallinium Cations

Reaction of a series of zerovalent Fe Lewis bases with Lewis acid GaCl3 leads to both conventional, neutral metal-only Lewis pairs in the case of small metal complexes and cationic gallenium species in the case of larger metal bases. The results suggest the predominance of steric bulk in controlling the outcome of group 13 trihalide Lewis acid additions to metal bases.