Metal‐Free Michael‐Addition‐Initiated Three‐Component Reaction for the Regioselective Synthesis of Highly Functionalized Pyridines: Scope, Mechanistic Investigations and Applications

A metal‐free and completely regioselective three‐component synthesis of highly functionalized pyridines from 1,3‐dicarbonyl derivatives and Michael acceptors has been achieved. Activated Michael acceptors, that is, β,γ‐unsaturated α‐oxo carbonyl derivatives, were utilized, allowing substitution at the 4‐position and remarkable functional diversity at the 2‐position of the pyridine ring. The scope and limitations of this environmentally friendly domino reaction are disclosed, with full experimental data, and the results of mechanistic investigations are discussed.