Nickel-Catalyzed Addition Research Articles

Dynamic kinetic asymmetric arylation and alkenylation of ketones.

Despite the importance of enantioenriched alcohols in medicinal chemistry, total synthesis, and materials science, the efficient and selective construction of enantioenriched tertiary alcohols bearing two contiguous stereocenters has remained a substantial challenge. We report a platform for their preparation through the enantioconvergent, nickel-catalyzed addition of organoboronates to racemic, nonactivated ketones. We prepared several important classes of α,β-chiral tertiary alcohols in a single step with high levels of diastereo- and enantioselectivity through a dynamic kinetic asymmetric addition of aryl and alkenyl nucleophiles. We applied this protocol to modify several profen drugs and to rapidly synthesize biologically relevant molecules. We expect this nickel-catalyzed, base-free ketone racemization process to be a widely applicable strategy for the development of dynamic kinetic processes.

Nickel-Catalyzed Addition of C-C Bonds of Amides to Strained Alkenes: The 1,2-Carboaminocarbonylation Reaction.

C(aryl)-C(═O) bonds of aryl amides can be activated and added across alkenes with the aid of a nickel catalyst. This 1,2-carboaminocarbonylation reaction enables the dicarbofunctionalization of alkenes with an atom economy of 100%.

Mechanistic Investigation on Hydrocyanation of Butadiene: A DFT Study

The nickel-catalyzed addition of Hydrocyanic acid (HCN) to butadiene usually leads to a mixture of the branched 2-methyl-3-butenenitrile (2M3BN) and the linear 3-pentenenitrile (3PN) with a 30:70 ratio by employing mono-dentate phosphites, while a 97% selectivity to 3PN is obtained using a 1,4-bis(diphenyphosphino)butane (dppb) ligand and Ni(COD)2 (1,5-Cyclooctadiene) as catalysts. To explain this phenomenon, a reasonable mechanism of the hydrocyanation, involving the cyano (CN) migration (for 3PN) and the methylallyl rotation (for 2M3BN) pathways, is proposed. The key intermediates and the rate-determining steps in the pathways have been illustrated. The methylallyl rearrangement is the rate-determining step in the formation of 3PN while the reductive elimination governs the reaction to 2M3BN, which is subsequently isomerized to 3PN. Moreover, the opposite changes of the bite angle of the intermediates and transition states explain how the reactions proceed in two different directions.

Nickel-Catalyzed Addition of Aryl Bromides to Aldehydes To Form Hindered Secondary Alcohols

Transition-metal-catalyzed addition of aryl halides across carbonyls remains poorly developed, especially for aliphatic aldehydes and hindered substrate combinations. We report here that simple nickel complexes of bipyridine and PyBox can catalyze the addition of aryl halides to both aromatic and aliphatic aldehydes using zinc metal as the reducing agent. This convenient approach tolerates acidic functional groups that are not compatible with Grignard reactions, yet sterically hindered substrates still couple in high yield (33 examples, 70% average yield). Mechanistic studies show that an arylnickel, and not an arylzinc, adds efficiently to cyclohexanecarboxaldehyde, but only in the presence of a Lewis acid co-catalyst (ZnBr2).

Nickel-Catalyzed Addition of Arylboronic Acids to Alkyl Nitriles for Synthesis of Aryl Ketones in Fluorinated Solvent

A mild and efficient nickel-catalyzed addition of arylboronic acids to alkyl nitriles in a fluorinated solvent for the synthesis of various aryl ketones is described. A broad range of arylboronic acids and alkyl nitriles were investigated, and the desired products were obtained with good to excellent yields under the optimized conditions. This method provides an opportunity for the synthesis of aryl ketones from alkyl nitriles, especially acetonitrile, with a non-noble metal catalyst in one pot.

Nickel-Catalyzed Conjugate Addition of Silyl Ketene Imines to Indol-2-ones

Nickel-Catalyzed Conjugate Addition of Silyl Ketene Imines to Indol-2-ones

Nickel-Catalyzed Direct Synthesis of Aryl Olefins from Ketones and Organoboron Reagents under Neutral Conditions

Nickel-catalyzed addition of arylboron reagents to ketones results in aryl olefins directly. The neutral condition allows acidic protons of alcohols, phenols, and malonates to be present, and fragile structures are also tolerated.

Enantioselective Nickel-Catalyzed anti-Carbometallative Cyclizations of Alkynyl Electrophiles Enabled by Reversible Alkenylnickel E/Z Isomerization.

Nickel-catalyzed additions of arylboronic acids to alkynes, followed by enantioselective cyclizations of the alkenylnickel species onto tethered ketones or enones, are reported. These reactions are reliant upon the formal anti-carbonickelation of the alkyne, which is postulated to occur by the reversible E/Z isomerization of an alkenylnickel species.

Nickel-Catalyzed Addition and Coupling Reaction of Aryl Triflates to Aldehydes

Nickel-Catalyzed Addition and Coupling Reaction of Aryl Triflates to Aldehydes

Enantioselective Nickel-Catalyzed Addition of Alcohols or Peroxides to Ketimines

Enantioselective Nickel-Catalyzed Addition of Alcohols or Peroxides to Ketimines

Nickel-Catalyzed Direct Addition of Diorganozinc Reagents to Phthalimides: Selective Formation of Gamma-Hydroxylactams

The nickel-catalyzed addition of diorganozinc reagents to phthalimides proceeds with excellent selectivity to provide 3-substituted-3-hydroxyisoindolin-1-one products. These 3-hydroxy-γ-lactams are produced cleanly in high yield with numerous examples of imide substitution and a broad range of diorganozinc reagents that are prepared and utilized without purification.

Nickel-Catalyzed Asymmetric Michael Additions with 2-Acetylazaarenes

Nickel-Catalyzed Asymmetric Michael Additions with 2-Acetylazaarenes

ChemInform Abstract: Stereochemistry in Palladium- and Nickel-Catalyzed Addition of Phenylmagnesium Bromide to Unsaturated Carbohydrates.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Direct Synthesis of Arylketones by Nickel-Catalyzed Addition of Arylboronic Acids to Nitriles

A convenient and efficient method for the synthesis of various arylketones by nickel-catalyzed addition of arylboronic acids to nitriles is described. A catalytic cycle involving Ni(II) species as the catalytic intermediates is proposed to account for the present catalytic reaction.

Nickel-Catalyzed Addition of Organo-boronates to Aldehydes and Ketones

A Ni(0)-NHC catalyst efficiently promotes the 1,2-addition of arylboronate esters to carbonyl compounds. This method allows obtaining a variety of benzylic alcohols, including sterically hindered ones and substituted triarylmethanols. The procedure is relatively simple, employs mild conditions, and tolerates the presence of various functional groups in the reactants.

Nickel-Catalyzed Cycloaddition of Salicylic Acid Ketals to Alkynes via Elimination of Ketones

An intermolecular nickel-catalyzed addition reaction has been developed where salicylic acid ketals react with alkynes to afford substituted chromones. A mechanistic rationale is proposed, implying beta-elimination of ketone from ring strained seven-membered nickelacycle to generate a five-membered oxa-nickelacycle intermediate.

Application of Enantiopure 1-(Aminoalkyl)naphthols and 2-(Aminoalkyl)phenols in the Enantioselective Addition of Organozinc to α,β-Unsaturated Carbonyl Compounds

Several enantiopure 1-(aminoalkyl)naphthols and a 2-(aminoalkyl)phenol were tested as ligands in the Nickel-catalyzed enantioselective addition of organozinc to chalcones.

Nickel-Catalyzed Decarboxylative Carboamination of Alkynes with Isatoic Anhydrides

An intermolecular nickel-catalyzed addition reaction in which isatoic anhydrides react with alkynes to afford substituted quinolones has been developed. A mechanistic rationale is proposed, implying oxidative addition of Ni(0) to a carbamate, which allows intermolecular addition to alkynes via decarboxylation.

Nickel-Catalyzed Decarbonylative Addition of Anhydrides to Alkynes

An intermolecular nickel-catalyzed addition reaction has been developed where phthalic anhydrides react with alkynes to afford substituted isocoumarins. A mechanistic rationale is proposed, implying reductive elimination of Ni(0) promoted by ZnCl(2) cocatalyst as the key step of the catalytic cycle.

ChemInform Abstract: Nickel‐Catalyzed Decarbonylative Addition of Phthalimides to Alkynes.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.