Reaction of the cyclic guanidine TolN?SIMe with the aluminum(I) compound NacNacAl (1) results in the unprecedented cleavage of the C–N multiple bond to give, after rearrangement, the carbene-ligated Al(III) amide, NacNac?Al(NHTol)(SIMe) (6). DFT calculations revealed that these reactions proceed via a bimolecular mechanism in which either the basic Al(I) center or the transient Al?NTol species