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Nickel nitrate
Nickel nitrate, Ni(NO₃)₂, is the nickel(2+) salt of nitric acid, best known as its emerald green hexahydrate and used as a strong oxidizer in nickel plating.
Nickel oxyhydroxide
Nickel oxyhydroxide (NiOOH) is a nickel compound formed when nickel hydroxide is oxidized, best known as the active material in nickel battery electrodes and water-splitting catalysts.
Nickel phosphide
Nickel phosphide is the family of crystalline nickel–phosphorus compounds, six stable phases below 800 °C, used as low-cost, noble-metal-free electrocatalysts for hydrogen production and water splitting.
Nickel photoredox catalysis
Nickel photoredox catalysis, also called metallaphotoredox or Ni/photoredox dual catalysis, pairs a nickel cross-coupling catalyst with a photoredox catalyst, using visible light to form bonds like sp³–sp³ couplings that neither catalyst achieves alone.
Nickel sulfate
Nickel sulfate (NiSO₄) is the water-soluble nickel(II) salt of sulfuric acid, sold mainly as blue-green crystalline hydrates and used in electroplating, nickel-cadmium batteries, and other nickel compounds.
Nickel sulfide
Nickel sulfide (NiS) is a dark green to black inorganic compound of nickel and sulfur that occurs as the mineral millerite and causes spontaneous breakage in tempered glass.
Nickel tetracarbonyl
Nickel tetracarbonyl, commonly called nickel carbonyl, is a colorless, volatile, highly toxic liquid of formula Ni(CO)4 discovered by Ludwig Mond in 1890, best known as the intermediate of the Mond process for refining high-purity nickel.
Nickel-catalyzed alkene dicarbofunctionalization
Nickel-catalyzed alkene dicarbofunctionalization, also known as conjunctive cross-coupling, is a family of organic reactions installing two carbon-based fragments across an alkene's double bond to form two C–C bonds in one operation.
Nickel-catalyzed C–H functionalization
Nickel-catalyzed C–H functionalization is a set of organic synthesis methods in which nickel complexes convert carbon–hydrogen bonds directly into carbon–carbon or carbon–heteroatom bonds, a low-cost alternative to palladium first demonstrated in 1963.
Nickel-catalyzed C–O activation of aryl esters in cross-coupling
Nickel-catalyzed C–O activation of aryl esters is a cross-coupling strategy in which nickel cleaves an ester's aryl–oxygen bond, established independently by Garg and Shi in 2008.
Nickel-catalyzed C–O cross-coupling
Nickel-catalyzed C–O cross-coupling is a family of reactions in which a nickel catalyst cleaves carbon–oxygen bonds in aryl ethers, esters, and related phenol derivatives to form new bonds.
Nickel-catalyzed carboxylation with CO2
Nickel-catalyzed carboxylation with CO2 is a family of reactions using nickel catalysts and carbon dioxide to convert organic halides, alkenes, and C–H bonds into carboxylic acids.
Nickel-catalyzed coupling of alcohols via photoredox
Nickel-catalyzed coupling of alcohols via photoredox, often called metallaphotoredox catalysis, combines a visible-light photocatalyst with nickel to form carbon–carbon and carbon–oxygen bonds from alcohols under mild conditions.
Nickel-catalyzed cross-coupling
Nickel-catalyzed cross-coupling is a family of organic synthesis reactions in which a nickel catalyst joins two coupling partners, forming carbon–carbon or carbon–heteroatom bonds; first reported in 1972.
Nickel-catalyzed cross-coupling of esters via C–O activation
Nickel-catalyzed cross-coupling of esters via C–O activation is a family of organic reactions in which a nickel catalyst cleaves an ester's C–O bond to form a carbon–carbon bond.
Nickel-catalyzed cross-coupling of tertiary alkyl electrophiles
Nickel-catalyzed cross-coupling of tertiary alkyl electrophiles is a family of reactions in which nickel catalysts join sterically hindered tertiary alkyl halides to partners, often forging all-carbon quaternary stereocenters.
Nickel-catalyzed cyanation
Nickel-catalyzed cyanation is a family of organic reactions in which a nickel catalyst installs a cyano group onto organic molecules, first reported by the Cassar group in 1973.
Nickel-catalyzed decarbonylative functionalization of amides
Nickel-catalyzed decarbonylative functionalization of amides is a set of organic reactions in which a nickel catalyst cleaves an amide's carbon-nitrogen bond and forms new carbon-carbon or carbon-heteroatom bonds.
Nickel-catalyzed enantioconvergent cross-coupling
Enantioconvergent nickel cross-coupling of racemic electrophiles is a family of catalytic reactions in which a chiral nickel catalyst converts both enantiomers of a racemic electrophile into one enantiomer.
Nickel-catalyzed enantioselective reductive cross-coupling
Nickel-catalyzed enantioselective reductive cross-coupling is a carbon–carbon bond-forming reaction in which a chiral nickel catalyst joins two electrophiles using a terminal reductant, first reported stereoconvergently in 2013.
Nickel-catalyzed reductive cross-electrophile coupling
Nickel-catalyzed reductive cross-coupling, also called cross-electrophile coupling, is a carbon-carbon bond-forming reaction where a nickel catalyst joins two organic electrophiles, such as two halides, under reducing conditions, without needing organometallic reagents.
Nickel-catalyzed Suzuki–Miyaura coupling of amides
A cross-coupling reaction in which a nickel catalyst cleaves the carbon–nitrogen bond of an amide and couples it with an organoboron reagent, converting amides into biaryl ketones.
Nickel-catalyzed β-carbon elimination
Nickel-catalyzed β-carbon elimination is an organometallic reaction step in which a carbon–carbon bond β to a nickel–carbon bond breaks, the analog of β-hydride elimination, prominently opening strained rings like cyclobutanones.
Nickel–iron oxyhydroxide OER catalysts
Nickel–iron oxyhydroxide OER catalysts, usually written NiFeOOH, are earth-abundant materials that catalyze the oxygen evolution reaction in alkaline water electrolysis and are leading alternatives to noble-metal catalysts like IrO2 and RuO2.
Nickel(II) oxide
Nickel(II) oxide, also known as nickel monoxide or green nickel oxide, is a green-to-black inorganic compound of nickel and oxygen with the formula NiO, used in pigments, smart windows, and solar cells.
Nickel/photoredox C–sp3–H cross-coupling
Nickel/photoredox C–sp3–H cross-coupling is a dual-catalytic organic method in which a visible-light photocatalyst generates carbon radicals from C–H bonds for nickel to couple with electrophiles.
Nickel/photoredox C(sp3)–C(sp2) cross-coupling
Nickel/photoredox C(sp3)–C(sp2) cross-coupling, or metallaphotoredox catalysis, is a dual-catalytic method joining alkyl carbons to aryl or vinyl carbons, first reported in 2014 by the Molander and Doyle/MacMillan groups.
Nickel/photoredox dual catalytic cross-coupling
Nickel/photoredox dual catalytic cross-coupling is a method for forming carbon–carbon bonds in which a nickel catalyst and a visible-light photocatalyst operate as interwoven cycles, first demonstrated in 2014.
Nickelate superconductors
Nickelate superconductors are nickel oxide compounds that show unconventional superconductivity, beginning in 2019 and studied as a third family of high-temperature superconductors alongside cuprates and iron-based materials.
Nicklas G. Pisias
Nicklas G. Pisias is an American paleoceanographer and Professor Emeritus at Oregon State University, known for work on orbital forcing of ice age cycles and deep-sea isotope records.