Palladium‐Catalyzed β  − Carbonyl Alkylation of α ‐Imino Esters With Allylic/Propargyl Alcohols

ABSTRACT A palladium‐catalyzed β ‐carbonyl alkylation of α ‐imino esters with readily available allylic/propargyl alcohols has been developed, enabling efficient synthesis of structurally diverse δ ‐carbonyl‐ α ‐amino acid esters and carbonyl‐containing pyrrolidine derivatives. Mechanistic studies indicate that the reaction proceeds via a dehydrogenation‐Michael addition or [3 + 2] cyclization pathway. This method offers an atom‐economical and operationally straightforward strategy for the synthesis of highly functionalized Δ(1)‐pyrrolines and pyrrolidines.