Organic Letters, Journal Year: 2024, Volume and Issue: 27(1), P. 340 - 345
Published: Dec. 30, 2024
This work describes a chiral bifunctional squaramide/DBU sequential catalytic strategy for the enantioselective synthesis of nonfused eight-membered O-heterocycles through asymmetric addition ynones to β,γ-unsaturated α-ketoesters followed by regio- and diastereoselective cyclization adduct intermediates. Mechanistic experiments revealed that an isomerization process should be involved in ring formation step, origin high regioselectivity diastereoselectivity has also been elucidated DFT calculations.
Language: Английский