Isoelectronic Aluminium Analogues of Carbonyl and Dioxirane Moieties

We report the anion Al(NON^Ar)(Se)]^? (NON^Ar=O(SiMe₂NAr)₂]^2?, Ar=2,6‐iPr₂C₆H₃), which is an isoelectronic Group 13 metal analogue of the carbonyl group containing an aluminium–selenium multiple bond. It was synthesized in a single step from the reaction of the aluminyl anion Al(NON^Ar)]^? with elemental selenium. Spectroscopic, crystallographic, and computational analysis confirmed multiple bonding between aluminium and selenium. Addition of a second equivalent of selenium afforded the diselenirane, Al(NON^Ar)(κ²‐Se₂)]^?, which is an isoelectronic analogue of the dioxirane group.