Organonickel σ-Complexes—Key Intermediates of Electrocatalytic Cycles

Electrochemical reduction of nickel complexes with 2,2-bipyridyl in the presence of ortho-substituted aromatic bromides or white phosphorus leads to the formation of highly reactive organonickel -complexes that are capable of selectively reacting with diverse substrates with the formation of cross-association products. Mechanisms of electrocatalytic processes involving organic halides, chlorophosphines, white phosphorus, and nickel complexes with 2,2-bipyridyl are studied by the cyclic voltammetry and preparative electrolysis methods. Key intermediates of processes that occur in metallocomplex catalysis are determined.     

The influence of the sacrificial anode nature on the mechanism of electrochemical arylation and alkylation of white phosphorus

The material of the sacrificial anode has a substantial effect on the nature and yield of the target products of electrochemical phosphorylation of organic halides by white phosphorus in the presence of the nickel complexes with 2,2"-bipyridine. The use of the zinc anode results in the products with tricoordinated phosphorus, viz., triorganylphosphines, the reaction on the aluminum anode affords triorganylphosphine oxides, and the presence of Mg²⁺ ions in the reaction mixture provides the transformation of white phosphorus into cyclic phosphines (PhP)₅.     

Phosphorylated azahomo[60]fullerene: synthesis and electrochemical properties

A reaction of [60]fullerene with O,O-dibutyl azidophosphate affords a first representative of phosphorylated azahomo[60]fullerenes, which is easier to reduce electrochemically than the starting C₆₀.     

Electrochemical Generation of Pyrazolyl-Pyridyl N-Heterocyclic Carbene Complexes of Nickel

Russian Journal of Electrochemistry - By methods of cyclic voltammetry and preparative electrolysis, the electrochemical properties of sterically hindered imidazolium salt...     

α-Diphenylphosphino-N-(pyrazin-2-yl)glycine as a ligand in Ni-catalyzed ethylene oligomerization

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Electrocatalytic reactions involving the NiII—ZnII—2,2"-bipyridine system

Factors determining the effect of Zn^II ions on the catalytic activity of the Ni^II complexes with 2,2"-bipyridine (bpy) in the reduction of organohalides were elucidated by cyclic voltammetry and electrolysis. The mechanism proposed involves the reduction of the Ni^IIbpy complex to Ni⁰bpy, the oxidative addition of organohalides to the Ni⁰bpy complex, and nickel transmetallation with the cathode-generated Zn⁰ to form an organozinc compound.     

Electrochemical Reduction of Nickel Complexes with 2,2'-Bipyridine

Electrochemical reduction of a nickel complex with 2,2'-bipyridine is accompanied by competing coproportionation yielding paramagnetic Ni^I complexes. A decrease in the ligand concentration shifts the equilibrium to the side of the active form of the Ni⁰bipy catalyst.     

Reactivity of phosphine oxide H<Subscript>3</Subscript>PO in the reactions with ketones

The reactivity of the electrochemically generated phosphine oxide H₃PO towards ketones (acetone, ethyl methyl ketone, methyl n-propyl ketone, and tert-butyl methyl ketone) has been studied. It was found that this reaction led to the formation of mono- and bis(hydroxyalkyl)phosphine oxides of the formulas RR?(OH)P(O)H₂ and [RR?(OH)]₂P(O)H (R = Me; R´ = Me, Et, Pr) and represents the first example of the P—C bond formation involving the intermediate H₃PO.     

Nickel Complexes in C‒P Bond Formation

This review is a comprehensive account of reactions with the participation of nickel complexes that result in the formation of carbon–phosphorus (C‒P) bonds. The catalytic and non-catalytic reactions with the participation of nickel complexes as the catalysts and the reagents are described. The various classes of starting compounds and the products formed are discussed individually. The several putative mechanisms of the nickel catalysed reactions are also included, thereby providing insights into both the synthetic and the mechanistic aspects of this phosphorus chemistry.     

Electrochemical reactions of white phosphorus

The main electrochemical transformations of elemental (white) phosphorus were considered. Special attention was given to the recently developed processes of preparation of organophosphorus compounds (OPCs) with phosphorus-carbon bonds. The electrochemical approaches to the synthesis of OPCs from white phosphorus using organonickel and organozinc reagents are described. The importance of using the electrochemical methods for the generation of highly reactive phosphorus intermediates was shown for phosphine oxide H3PO obtained for the first time. This provides significant prospects for the electrochemical approaches that could be applied for the development of technologies of the chlorine-free synthesis of OPCs from white phosphorus.