This Review describes the application of nitroxides to synthesis and polymer chemistry. The synthesis and physical properties of nitroxides are discussed first. The largest section focuses on their application as stoichiometric and catalytic oxidants in organic synthesis. The oxidation of alcohols and carbanions, as well as oxidative C-C bond-forming reactions are presented along with other typical oxidative transformations. A section is also dedicated to the extensive use of nitroxides as trapping reagents for C-centered radicals in radical chemistry. Alkoxyamines derived from nitroxides are shown to be highly useful precursors of C-centered radicals in synthesis and also in polymer chemistry. The last section discusses the basics of nitroxide-mediated radical polymerization (NMP) and also highlights new developments in the synthesis of complex polymer architectures.

Nitroxides: applications in synthesis and in polymer chemistry.

A radical outlook: Recently published "organocatalytic C-H activation reactions" have now been interpreted as base-promoted homolytic substitutions. The addition of an aryl radical to an arene followed by deprotonation (see above) and electron transfer form part of the chain reaction. Although these new results are not conceptual breakthroughs, they could be experimental breakthroughs because they presage new transformations in radical (anion) chemistry. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Organocatalysis and C-H activation meet radical- and electron-transfer reactions.

Double-hybrid density functionals (DHDFs) are reviewed in this study. In DHDFs parts of conventional density functional theory (DFT) exchange and correlation are replaced by contributions from nonlocal Fock-exchange and second-order perturbative correlation. The latter portion is based on the well-known MP2 wave-function approach in which, however, Kohn–Sham orbitals are used to calculate its contribution. First, related methods preceding this idea are reviewed, followed by a thorough discussion of the first modern double-hybrid B2-PLYP. Parallels and differences between B2-PLYP and its various successors are then outlined. This discussion is rounded off with representative thermochemical examples demonstrating that DHDFs belong to the most robust and accurate DFT approaches currently available. This analysis also presents hitherto unpublished results for recently developed DHDFs. Finally, how double-hybrids can be combined with linear-response time-dependent DFT is also outlined and the value of this approach for electronically excited states is shown. WIREs Comput Mol Sci 2014, 4:576–600. doi: 10.1002/wcms.1193

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Conflict of interest: The authors have declared no conflicts of interest for this article.

Double‐hybrid density functionals

Where HAS you been? A manganese-mediated annulation of 2-isocyanobiaryls with organoboronic acids is developed for the synthesis of a broad range of phenanthridine derivatives. Mechanistic studies indicate that the reaction proceeds by the intramolecular homolytic aromatic substitution (HAS) of an imidoyl radical intermediate.

Santiago E. Vaillard

Papers

Homolytic substitution at phosphorus for the synthesis of alkyl and aryl phosphanes.

Radical‐Based Arylation Methods

Radical Amination with Trimethylstannylated Benzophenone Imine

Homolytische Substitution am Phosphor zur Synthese von Alkyl‐ und Arylphosphanen

Homolytic Substitution at Phosphorus for the Synthesis of Alkyl and Aryl Phosphanes.