New Carbon-Carbon Bond Forming Reactions Promoted by Aluminyl and Alumoxane Anions: Introducing the Ethenetetraolate Ligand.

[K{Al(NONDipp)}](2) (NONDipp=[O(SiMe(2)NDipp)(2)](2-), Dipp=2,6-iPr(2)C(6)H(3)) 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-).