Stereoselective Synthesis
of Dihydrocoumarins via
[1,2]-Phospha-Brook Rearrangement in Three-Component Coupling Reaction
of α‑Ketoesters, o‑Quinone Methides,
and Dialkyl Phosphites
posted on 2021-10-12, 17:05authored byRavneet Kaur, Dipak Singh, Ravi P. Singh
A highly
regio- and diastereoselective approach for the synthesis
of phosphate substituted dihydrocoumarins via Brønsted base catalyzed
[1,2]-phospha-Brook rearrangement is reported. The two-step, one-pot
Michael addition of α-phosphonyloxy enolates proceeds by coupling
of dialkyl phosphite and α-ketoesters to o-quinone
methides, followed by an intramolecular cyclization, providing 3,4-dihydrocoumarin
frameworks.