Potassium Aluminyl Promoted Carbonylation of Ethene.

The potassium aluminyl [K{Al(NON )}] ([NON ] =[O{SiMe NDipp} ] , Dipp=2,6-iPr C H ) activates ethene towards carbonylation with CO under mild conditions. An isolated bis-aluminacyclopropane compound reacted with CO via carbonylation of an Al-C bond, followed by an intramolecular hydrogen shift to form K [Al(NON )(μ-CH CH=CO-1κ C -2κO)Al(NON )Et]. Restricting the chemistry to a mono-aluminium system allowed isolation of [Al(NON )(CH CH CO-κ C )] , which undergoes thermal isomerisation to form the [Al(NON )(CH CH=CHO-κ C,O)] anion. DFT calculations highlight the stabilising influence of incorporated benzene at multiple steps in the reaction pathways.