Highly Regio‐ and Stereoselective Intermolecular Seleno‐ and Thioamination of Alkynes

Abstract

By using N-fluorobenzenesulfonimide as both the oxidant and the amination reagent, we have realized the first example of the intermolecular chalcogenative amination of alkynes, which grants facile, highly regio- and stereoselective access to chalcogenated enamides. The reaction features mild conditions, high yields and selectivities, remarkably broad substrate scope, and excellent functional group tolerance. Mechanistic studies indicate the in situ generated chalcogen imidates to be the actual reactive species, which in turn, has clarified the mechanism of related transformations. These reactions represent significant additions to the development of the highly selective amino bisfunctionalization of alkynes.

Synthesis of Aminoallenes via Selenium‐π‐Acid‐Catalyzed Cross‐Coupling of N‐Fluorinated Sulfonimides with Simple Alkynes

“…Based on these observations, we propose the following catalytic cycle for the title reaction (Scheme 2). First, oxidation of the diselenide by NFSI, followed by the addition onto alkyne 1 may lead to the formation of selenirenium ion 6 , [21] which is subsequently attacked by the sulfonimide anion, forming selenoamination adduct 4 [22] . After oxidation of the selenium moiety and coordination onto another alkyne molecule, potentially leading to Lewis‐adduct 8 , allene 2 and selenirenium ion 6 are formed.…”

Three‐Component Coupling Reactions of Maleimides, Thiols, and Amines: One‐Step Construction of 3,4‐Heteroatom‐functionalized Maleimides by Copper‐Catalyzed C(sp2)−H Thioamination

“…recently developed efficient thioamination of alkenes mediated by iodine(III) reagents . Subsequently, highly regio‐ and stereo‐selective intermolecular seleno‐ and thioamination of alkynes was reported by Zheng . Yoshida also described a direct thioamination of arynes via reaction with sulfilimines and migratory N‐arylation to give o‐sulfanylanilines in high yield .…”

Synthesis of Seleno‐Heterocycles via Electrophilic/Radical Cyclization of Alkyne Containing Heteroatoms

“…NFSI plays a dual role as the oxidant and the amination reagent, the regio-and stereoselective chalcogenated enamides 334 were successfully synthesized (Scheme 106). [201][202] have focused on the use of Cu, [205][206][207] Fe, [208][209][210] Ag [211] and In-based [212] catalytic systems (Scheme 107). [203][204][205][206][207][208][209][210][211][212]…”