C-C, C-O, C-N bond formation on sp2 carbon by Pd(II)-catalyzed reactions involving oxidant agents.

Alkylation reactions represent an important organic transformation to form C–C bonds. In addition to conventional approaches with alkyl halides or sulfonates as alkylating agents, the use of unactivated olefins for alkylations has become attractive from both cost and sustainability viewpoints. This Review summarizes transition-metal-catalyzed alkylations of various carbon–hydrogen bonds (addition of C–H bonds across olefins) using regular olefins or 1,3-dienes up to May 2016. According to the mode of activation, the Review is divided into two sections: alkylation via C–H activation and alkylation via olefin activation.

Transition-Metal-Catalyzed C–H Alkylation Using Alkenes

Over the past decade, copper-catalyzed atom transfer radical polymerization (ATRP) has had a tremendous impact on the synthesis of polymeric materials with well defined compositions, architectures and functionalities. Apart from synthetic aspects of ATRP, considerable effort has also been devoted to structural and mechanistic understanding of copper complexes involved in ATRP, as well as development of methodologies to decrease the amount of catalyst needed in these systems. This tutorial review reports on recent advances in the area of catalyst regeneration in ATRP and mechanistically similar atom transfer radical addition (ATRA) using environmentally benign reducing agents. The outlined processes termed ARGET (activators regenerated by electron transfer) and ICAR (initiators for continuous activator regeneration) ATRP enable the synthesis of well-defined (co)polymers and single addition adducts using very low concentrations of copper catalysts (1–100 ppm). Recent developments in this area could have profound industrial implications on the synthesis of well-defined polymeric materials and small organic molecules.

Atom transfer radical addition and polymerization reactions catalyzed by ppm amounts of copper complexes

The high utility of halogenated organic compounds has prompted the development of a vast number of transformations which install the carbon–halogen motif. Traditional routes to these building blocks have commonly involved multiple steps, harsh reaction conditions, and the use of stoichiometric and/or toxic reagents. In this regard, using transition metals to catalyze the synthesis of organohalides has become a mature field in itself, and applying these technologies has allowed for a decrease in the production of waste, higher levels of regio- and stereoselectivity, and the ability to produce enantioenriched target compounds. Furthermore, transition metals offer the distinct advantage of possessing a diverse spectrum of mechanistic possibilities which translate to the capability to apply new substrate classes and afford novel and difficult-to-access structures. This Review provides comprehensive coverage of modern transition metal-catalyzed syntheses of organohalides via a diverse array of mechanisms. Atte...

Modern Transition-Metal-Catalyzed Carbon–Halogen Bond Formation

N-Heterocyclic carbenes (NHC) are nowadays ubiquitous and indispensable in many research fields, and it is not possible to imagine modern transition metal and main group element chemistry without t...

Qiang Gao

Papers

Ni(II)-catalyzed Conia-ene reaction of 1,3-dicarbonyl compounds with alkynes.

Enantioselective PhSe-group-transfer tandem radical cyclization reactions catalyzed by a chiral Lewis acid.

Lanthanide Triflate-Promoted Palladium-Catalyzed Cyclization of Alkenyl β-Keto Esters and Amides

Copper(I)-catalyzed chlorine atom transfer radical cyclization reactions of unsaturated α-chloro β-keto esters

Novel Intramolecular Cyclopropanation Reaction of Unsaturated β-Keto Esters