Fe(III)-Based Tandem Catalysis for Amidomethylative Multiple Substitution Reactions of α-Substituted Styrene Derivatives

Abstract

Developing tandem multiple C–H substitution reactions of simple alkenes provides rapid access to structurally complex unsaturated building blocks. Amidomethylative reactions that reserve C═C double bonds have been composed sequentially for tandem catalytic substitutions around the C═C bonds of alkenes. As a proof-of-concept demonstration, tandem catalytic amidomethylative processes, which effectively form multiple C–C bonds, have been developed to directly and selectively transform α-substituted styrenes into unsaturated N-heterocycles. Using Fe(OTf)3 as the sole catalyst, the operationally simple protocols employ bench-stable bisamidomethane as the sole reagent to produce hexahydropyrimidines and 1,2,3,6-tetrahydropyridine derivatives. Moreover, the practical catalytic processes constituted facile two-step pathways, from simple α-substituted styrenes, to access unsaturated 1,3-diamine and bispidine derivatives.