Carbon–Carbon Bond Forming Reactions Promoted by Aluminyl and Alumoxane Anions: Introducing the Ethenetetraolate Ligand

[K{Al(NONDipp)}]2 (NONDipp=[O(SiMe2NDipp)2]2−, Dipp=2,6‐iPr2C6H3) reacts with CS2 to afford the trithiocarbonate species [K(OEt2)][Al(NONDipp)(CS3)] 1 or the ethenetetrathiolate complex, [K{Al(NONDipp)(S2C)}]2 [3]2. The dimeric alumoxane [K{Al(NONDipp)(O)}]2 reacts with carbon monoxide to afford the oxygen analogue of 3, [K{Al(NONDipp)(O2C)}]2 [4]2 containing the hitherto unknown ethenetetraolate ligand, [C2O4]4−. K[Al(NONDipp)] has been used to construct new C=C double bonds. The reaction with CS2 generates the ethenetetrathiolate [C2S4]4− containing product through a reductive coupling strategy. To obtain similar carbon–oxygen products, the alumoxane [K{Al(NONDipp)(O)}]2 was reacted with CO, affording a hitherto unknown ethenetetraolate [C2O4]4− ligand. DFT analysis indicates retention of a bimetallic species throughout the reaction with CO.