Visible light bromide catalysis for oxazoline, pyrrolidine, and dihydrooxazine syntheses via Csp3-H functionalizations.

A catalytic benzylic Csp3-H functionalization protocol is described here. This visible light-mediated process is centered on the utilization of a bromide catalyst and oxidant to generate a nitrogen (N)-centered radical for a site-selective hydrogen atom transfer (HAT) process. This strategy enabled the unconventional syntheses of a number of N-heterocycles dependent on the amide identity. We also discovered a nucleophilicity-dependent kinetic resolution for stereochemical differentiation of Csp3-H bonds that enabled the stereoselective synthesis of cis- and trans-oxazolines.

Halonium Catalysis: An Underutilized and Underexplored Catalytic Concept in Olefin Functionalizations.

Iodonium catalysis is described here to accomplish an intermolecular olefin oxyamination reaction. Urea is used as the O- and N-source to add across both activated and unactivated alkenes in a regioselective manner. Mechanistic studies confirm the presence of an iodonium intermediate.