Potassium Aluminyl Promoted Carbonylation of Ethene
Matthew J. Evans, Samuel E. Neale, Mathew D. Anker, Claire L. McMullin, Martyn P. Coles
Abstract
Abstract The potassium aluminyl [K{Al(NON Dipp )}] 2 ([NON Dipp ] 2− =[O{SiMe 2 NDipp} 2 ] 2− , Dipp=2,6‐ i Pr 2 C 6 H 3 ) 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 2 [Al(NON Dipp )( μ ‐CH 2 CH=CO‐1κ 2 C 1,3 ‐2κ O )Al(NON Dipp )Et]. Restricting the chemistry to a mono‐aluminium system allowed isolation of [Al(NON Dipp )(CH 2 CH 2 CO‐κ 2 C 1,3 )] − , which undergoes thermal isomerisation to form the [Al(NON Dipp )(CH 2 CH=CHO‐κ 2 C , O )] − anion. DFT calculations highlight the stabilising influence of incorporated benzene at multiple steps in the reaction pathways.