Mechanistic proposals for nickel-catalyzed coupling reactions often invoke five-coordinate alkyl- or aryl-bound Ni(II) and/or high-valent nickel(III) species, but because of their reactive nature, they have been difficult to study and fingerprint. In this work, we invoked the stabilizing properties of fluoroalkyl ligands to access such nickel species bearing ligands that are commonplace in organic coupling reactions. We show that five-coordinate Ni(II) complexes containing nickel-carbon bonds can readily be prepared given the appropriate precursor, and we also present evidence for the formation of Ni(III) species upon chemical and electrochemical oxidation of the five-coordinate complexes.

Inexpensive nickel-bipyridine complexes were found to be active for the trifluoromethylthiolation of aryl iodides and aryl bromides at room temperature using the convenient [NMe(4)][SCF(3)] reagent.

Well-defined copper and gold complexes have been prepared which contain the shortest structurally characterized metal−oxygen bonds between transition metals and a trifluoromethoxide moiety. The trifluoromethoxide ligand is O-bound to both the copper and gold centers, with a copper−oxygen distance of 1.849(4) Å and a gold−oxygen distance of 2.058(4) Å. Density functional theory (DFT) calculations on all new trifluoromethoxy complexes were performed in order to obtain bond lengths and angles that are not influenced from any intermolecular contacts in the solid state and also to provide a first glimpse of the electronic features of this previously unknown ligand.The trifluoromethoxide group has recently been described as "the least well-understood" fluorine-containing substituent. 1

All you need is air: A new protocol has been developed which can mediate the coupling of aryl and vinyl boronic acids at room temperature in high yields (see scheme, dtbpy=4,4′‐di‐tert‐butyl‐2,2′‐bipyridine). The reactions take place using simple copper(II) salts under aerobic conditions and do not require the use of expensive silver oxidants.

Recent advances in aqueous fluoroalkylation using various fluoroalkylation reagents are summarized in this review.