Shedding Light on the Diverse Reactivity of NacNacAl with N-Heterocycles.

The aluminum(I) compound NacNacAl (NacNac=[ArNC(Me)CHC(Me)NAr]- , Ar=2,6-iPr2 C6 H3 , 1) shows diverse and substrate-controlled reactivity in reactions with N-heterocycles. 4-Dimethylaminopyridine (DMAP), a basic substrate in which the 4-position is blocked, induces rearrangement of NacNacAl by shifting a hydrogen atom from the methyl group of the NacNac backbone to the aluminum center. In contrast, C-H activation of the methyl group of 4-picoline takes place to produce a species with a reactive terminal methylene. Reaction of 1 with 3,5-lutidine results in the first example of an uncatalyzed, room-temperature cleavage of an sp2 C-H bond (in the 4-position) by an AlI species. Another reactivity mode was observed for quinoline, which undergoes 2,2'-coupling. Finally, the reaction of 1 with phthalazine produces the product of N-N bond cleavage.