Carbon−Carbon Bond Formation with Electrogenerated Nickel and Palladium Complexes

Abstract

We report coupling reactions of organic derivatives through catalysis by nickel and palladium complexes combined with electrochemical methods. Arylation, carboxylation, carbonylation, cyclisation, alkylation, and other reductive C−C bond forming reactions of organic halide derivatives, unsaturated

New Insights into the Stoichiometric and Catalytic Reactivity of Unsaturated Pd3(dppm)3COn+ Clusters (n = 0, 1) Towards Halocarbons – First Evidence for Inorganic By‐Products

“…[43] Thus, the indirect reduction of RX using an electron transfer catalyst mediating the RX conversion to "R · " is appealing. [44] In an attempt to render the stoichiometric reactions for "Bz · " described above catalytic, two methodologies were examined. The first involves Pd 3 (Br) + as a precatalyst in a single compartment electrochemical cell equipped with a copper anode as the controlled-potential working electrode, a platinum cathode as the counter-electrode and CH 2 Cl 2 as the solvent.…”

Catalytic reduction of 1-iodooctane by nickel(I) salen electrogenerated at carbon cathodes in dimethylformamide: Effects of added proton donors and a mechanism involving both metal- and ligand-centered one-electron reduction of nickel(II) salen

“…Subsequent investigations of processes catalyzed by nickel(I) tetraazamacrocyclic complexes were carried out by Bakac, Espenson, and Ram [6][7][8][9][10]14,15], and Stolzenberg and co-workers probed nickel(I) hydroporphyrin-catalyzed reductions of alkyl halides [11][12][13]17,20]. A number of interesting reductive cyclizations of halogenated compounds promoted by electrogenerated nickel(I) species have been reported by Ozaki and co-workers [16,19,22,23,[25][26][27][28] and by Duñ ach et al [24,[29][30][31]33,35,[37][38][39][40]. Additional papers have appeared from the laboratories of Helvenston and Castro [18], Fry and Fry [21], Esteves and co-workers [32], and Gennaro and Isse [34,36].…”

Catalysis by electrons and holes: formal potential scales and preparative organic electrochemistry

“…Pd(II), Ni(II) or Co(II) coordination complexes have been reported as mediators of this process (Scheme 10). 66,73 The reduced form of these complexes can be produced as the first step in the reaction. These species were shown to react further with organic halides to form reactive organometallic species that lead to productive chemistry.…”

“…A review of reactivity of electro-generated reduced species of Ni and Pd is available. 73 The potential at which the mediator is reduced is generally more positive than the potential necessary to directly reduce the organic halide. The reduced mediator species is then able to transfer reducing equivalents to the organic fragment to afford a radical species, R • , which can, in turn, become further reduced to an anion or react as a radical.…”