Photochemical and Electrochemical Applications of Proton-Coupled Electron Transfer in Organic Synthesis.

We present here a review of the photochemical and electrochemical applications of multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms in which both an electron and a proton are exchanged together, often in a concerted elementary step. As such, MS-PCET can function as a non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from a wide variety of common organic functional groups.

Intermolecular sp-C-H Amination for the Synthesis of Saturated Azacycles.

The preparation of substituted azetidines and larger ring, nitrogen-containing saturated heterocycles is enabled through efficient and selective intermolecular sp-C-H amination of alkyl bromide derivatives. A range of substrates are demonstrated to undergo C-H amination and subsequent sulfamate alkylation in good to excellent yield. -Phenoxysulfonyl-protected products can be unmasked under neutral or mild basic conditions to yield the corresponding cyclic secondary amines.

Intermolecular C(sp )-H Amination of Complex Molecules.

A general and operationally convenient method for intermolecular amination of C(sp )-H bonds is described. This technology allows for efficient functionalization of complex molecules, including numerous pharmaceutical targets. The combination of pivalonitrile as a solvent, Al O as an additive, and phenyl sulfamate as a nitrogen source affords differential reaction performance and substrate scope.

Cyanthiwigin Natural Product Core as a Complex Molecular Scaffold for Comparative Late-Stage C-H Functionalization Studies.

The desire for maximally efficient transformations in complex molecule synthesis has contributed to a surge of interest in C-H functionalization methods development in recent years. In contrast to the steady stream of methodological reports, however, there are noticeably fewer studies comparing the efficacies of different C-H functionalization protocols on a single structurally intricate substrate. Recognizing the importance of heteroatom incorporation in complex molecule synthesis, this report discloses a comparative examination of diverse strategies for C-O, C-N, and C-X bond formation through late-stage C-H oxidation of the tricyclic cyanthiwigin natural product core.