Direct C(sp)-H allylation of 2-alkylpyridines with Morita-Baylis-Hillman carbonates via a tandem nucleophilic substitution/aza-Cope rearrangement.

A base- and catalyst-free C(sp)-H allylic alkylation of 2-alkylpyridines with Morita-Baylis-Hillman (MBH) carbonates is described. A plausible mechanism of the reaction might involve a tandem S2' type nucleophilic substitution followed by an aza-Cope rearrangement. Various alkyl substituents on 2-alkylpyridines were tolerated in the reaction to give the allylation products in 26-91% yields. The developed method provides a straightforward and operational simple strategy for the allylic functionalization of 2-alkypyridine derivatives.