Diastereo- and enantioselective oxa-Nazarov cyclization-Michael addition of conjugated 1,2-diketones was achieved by using asymmetric binary-acid catalysis with chiral phosphoric acid and FeBr3.
Divergent approaches were developed to synthesize δ-valerolactones or furanones via a palladium or copper-catalyzed α-hydroxycyclopropanol ring opening cyclizations, respectively.
A halotrimethylsilane facilitated cycloketonization of γ-hydroxyl ynones is detailed for one-step synthesis of polysubstituted 3(2H)-furanone products.
Catalyst-free synthesis of 3(2H)-furanone derivatives has been achieved from metal-free cross-coupling of α-diazo ester and α-aryldiazo ketones.
Organocatalytic asymmetric Michael additions of aldehydes to 2-furanones are successfully conducted and have been applied to the synthesis of vorapaxar's analogues.