Direct access to a neutral alumene via CO reduction by a dialane and further CO homologation
John A. Kelly, Arseni Kostenko, Shigeyoshi Inoue
Abstract
Abstract Multiple bonds between heavy elements have been shown to be not only stable but also offer divergent reactivity. Accordingly, there has been a drive in research to isolate such species. Here we report on the synthesis of a compound containing an aluminium–carbon double bond (alumene). The alumene was formed by exposing a dialane to a CO atmosphere. Experimental data and quantum chemical calculations confirm the existence of a π -bond between the aluminium and carbon centre. The mechanism for the formation of the alumene was calculated and indicated a heterocyclic intermediate, which we were able to observe spectroscopically. Treating the alumene with excess CO leads to CO homologation, forming a C 3 O 2 chain initiated by interaction of a CO molecule with the π -bond of Al=C.