HFIP-Mediated, Regio-, and Stereoselective Hydrosulfenylation of Ynamides: A Versatile Strategy to Access Ketene N,S-Acetals

Organic & Biomolecular Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

Herein, we report an HFIP-mediated, versatile, sustainable, atom-economical, and regio- stereoselective hydro-functionalization of ynamides with various S-nucleophiles (1 equiv.) such as thiols, thiocarboxylic acids, carbamates, xanthates, O,O-diethyl S-hydrogen phosphorothioate to access a wide variety stereodefined trisubstituted ketene N,S-acetals under mild conditions. This protocol requires only HFIP, which plays multiple roles, acting Brønsted acid protonate the ynamide regioselectively at beta carbon generate reactive keteniminium intermediate, stabilizing intermediate solvent through H-bonding. After nucleophilic attack S-nucleophile on deprotonation, HFIP is regenerated in most cases can be easily recovered recycled, revealing high sustainability protocol. Remarkably, all reactions are highly efficient furnish excellent yields many pure products were obtained just by washing crude reaction mixture pentane. Significantly, green chemistry metrics found excellent.

Language: Английский

Transition Metal-free Direct C(sp2)-H Thiocyanation of 2-Iminothiazolines at Room Temperature

Tetrahedron, Journal Year: 2025, Volume and Issue: unknown, P. 134756 - 134756

Published: May 1, 2025

Language: Английский