Recent Advances in Asymmetric Catalytic Annulation of γ‐ and δ‐Hydroxy‐α,β‐Unsaturated Carbonyl Compounds for the Synthesis of Chiral Oxygen Heterocycles

ABSTRACT Oxygen‐containing heterocycles are increasingly recognized for their biological significance, especially in the field of drug discovery. Therefore, the enantioselective synthesis of these frameworks has become a central focus in modern organic chemistry, inspiring the development of numerous elegant synthetic strategies over the past few decades. Among the various building blocks available, γ‐ and δ‐hydroxy‐α,β‐unsaturated carbonyl compounds–bearing both an oxygen‐centered nucleophile and a Michael acceptor–have emerged as highly versatile synthons for the efficient construction of oxygen‐containing heterocycles through cascade annulation reactions. This review summarizes recent advances in the chemistry of these compounds, with particular emphasis on γ‐hydroxy‐α,β‐unsaturated ketones, δ‐hydroxy‐α,β‐unsaturated ketones, o ‐hydroxyphenyl‐α,β‐unsaturated ketones, and o ‐hydroxy‐cinnamaldehydes, highlighting their applications in the enantioselective synthesis of diverse chiral oxygen‐containing heterocycles via organocatalytic cascade reactions.