3 research outputs found
Synthesis of Bicyclic Imidazoles via [2 + 3] Cycloaddition between Nitriles and Regioselectively Generated α‑Imino Gold Carbene Intermediates
The cyclic α-imino gold carbene intermediate <b>B</b> is most likely generated in situ via regioselective nitrene transfer from an azido group to a tethered terminal alkyne in the presence of a gold catalyst and at ambient temperature. This highly electrophilic intermediate can react with a weakly nucleophilic nitrile, which is used as the reaction solvent, to deliver a bicyclic imidazole rapidly in an overall bimolecular [2 + 2 + 1] cycloaddition and in mostly serviceable yield. The competing intramolecular Huisgen reaction, although likely also catalyzed by gold, is minimized by using AuCl<sub>3</sub> as the catalyst
A One-Pot Construction of Halogenated Trifluoromethylated Pyrroles through NXS (X = Br, I) Triggered Cascade
An easy two-step,
one-pot synthesis of halogenated trifluoromethylated
pyrroles is realized by sequential intermolecular hydroamination reaction
of 2-trifluoromethyl-1,3-enynes with aliphatic primary amines under
mild reaction conditions, and NXS mediated oxidative cyclization of
the hydroamination product. The salient features of this method include
mild conditions, readily available starting materials, general substrate
scope, high efficiency and synthetic utility of the products