- Late-Stage Derivatization of Buflavine by Nickel-Catalyzed Direct Substitution of a Methoxy Group via C-O Bond Activation
-
The nickel-catalyzed cross-coupling of methoxyarenes was applied to buflavine, which allows for the selective monosubstitution of one of the two methoxy groups in the molecule, leading to the formation of 2- and 3-substituted isomers. Trimethylsilylmethyl (TMSCH 2), phenyl, and alkynyl groups can be introduced into buflavine using this method. The resulting TMSCH 2analogue of buflavine can also be converted into several other derivatives.
- Shimazumi, Ryoma,Morita, Kosuke,Yoshida, Tomoki,Yasui, Kosuke,Tobisu, Mamoru
-
p. 3037 - 3044
(2021/05/06)
-
- Recyclable and Stable α-Methylproline-Derived Chiral Ligands for the Chemical Dynamic Kinetic Resolution of free C,N-Unprotected α-Amino Acids
-
A novel special designed, stable, and recyclable chiral ligand bearing a quaternary carbon was developed for chemical dynamic kinetic resolution (DKR) of free C,N-unprotected racemic α-amino acids via Schiff base intermediates. This method furnishes high yields with excellent enantioselectivity, has a broad substrate scope, and uses operationally simple and convenient conditions. The present chemical DKR is a practical and useful method for the preparation of enantiopure α-amino acids.
- Shu, Shuangjie,Zhao, Liang,Zhou, Shengbin,Wu, Chenglin,Liu, Hong,Wang, Jiang
-
-
- Synthesis and characterization of unique nickel(II) carboxylates and their coordination complexes
-
Direct anodic dissolution of nickel metal and cathodic reduction of carboxylic acids (RCOOH) in acetonitrile has proved to be a simple and efficient one-step route to synthesize unique polymeric nickel(II) carboxylate complexes, {Ni(OOCR)2}n in H-type glass Pyrex cell. When the oxidation was carried out in the presence of neutral ligands (L) such as 2,2’-bipyridyl or 1,10-phenanthroline, the complexes of type {Ni(OOCR)2.L}n were obtained. Tetrabutylammonium chloride has been used as a supporting electrolyte in order to increase the electrolytic conductivity of the electrochemical system which in turn affects the current efficiency, cell voltage and energy consumption in the electrolytic cell. The complexes have been characterized by vibrational spectra, CHN elemental analysis, solubility and melting points shows a good agreement with the structure. The result also shows that the direct electrochemical synthetic technique has high current efficiency, extra purity and yield.
- Shavina,Singh, Baljit
-
p. 416 - 420
(2018/01/12)
-
- The Kinetics of Growth of Metallo-supramolecular Polyelectrolytes in Solution
-
Several transition metal ions, like Fe2+, Co2+, Ni2+, and Zn2+ complex to the ditopic ligand 1,4-bis(2,2′:6′,2′′-terpyridin-4′-yl)benzene (L). Due to the high association constant, metal-ion induced self-assembly of Fe2+, Co2+, and Ni2+ leads to extended, rigid-rod like metallo-supramolecular coordination polyelectrolytes (MEPEs) even in aqueous solution. Here, we present the kinetics of growth of MEPEs. The species in solutions are analyzed by light scattering, viscometry and cryogenic transmission electron microscopy (cryo-TEM). At near-stoichiometric amounts of the reactants, we obtained high molar masses, which follow the order Ni-MEPE≈Co-MEPEa reversible step-growth mechanism. The forward polymerization rate constants follow the order Co-MEPEFe-MEPENi-MEPE and the growth of MEPEs can be accelerated by adding potassium acetate.
- Munzert, Stefanie Martina,Stier, Simon P.,Schwarz, Guntram,Weissman, Haim,Rybtchinski, Boris,Kurth, Dirk G.
-
p. 2898 - 2912
(2017/10/06)
-
- Preparation method of battery grade nickel acetate
-
The invention relates to a preparation method of battery grade nickel acetate, and aims at providing a preparation method of battery grade nickel acetate, which is simple in production principle and wide in raw material source and facilitates industrial production. The preparation method of the battery grade nickel acetate comprises the following steps: metallic nickel powder and an acid copper chloride solution react, impurity removal and evaporation are carried out, and NiCl2 is obtained; NiCl2 is mixed with a sodium hydroxide solution fully, after filtration, Ni(OH)2 is obtained, nickelous hydroxide is washed and then is acidified by acetic acid, and nickel acetate is generated finally. The nickel acetate prepared by the preparation method is high in purity. The preparation method is applied to the technical field of chemical production.
- -
-
Paragraph 0038; 0041; 0042; 0043
(2017/08/29)
-
- A coarse granular nickel acetate method of crystallizing
-
The invention discloses a crystallization method of coarse particle nickel acetate. A nickel acetate crystal obtained through evaporating and condensing of a nickel acetate solution, adding of glacial acetic acid to regulate pH, cooling and crystalizing is regular in crystal form, as well as coarse, large and uniform in particles, and the crystal with the length between 0.5-1.0mm accounts for more than 75%. The process is simple and reliable, and is strong in operability. The nickel acetate product produced through the process is coarse and large in particle, dust pollution is avoided in the use process, and the physical and psychological health of an operator is not jeopardized.
- -
-
Paragraph 0019; 0021; 0022-0023; 0025
(2018/02/04)
-
- Protolytic dissociation mechanisms and comparative acid stabilities of palladium(II), zinc(II), copper(II), and nickel(II) complexes of alkylated dipyrrins
-
Complexes of Pd(II), Cu(II), Ni(II), and Zn(II) with alkylated dipyrrins (Hdpm) were synthesized and characterized by physicochemical and spectroscopic methods. Protolytic dissociation kinetics of these complexes in benzene in the presence of acetic and trichloroacetic acid was studied. A protonated dipyrrin is the reaction product of protolytic dissociation of the complexes in acid solutions. The observed and true dissociation rate constants, as well as activation reaction parameters, were calculated. Kinetic models of the processes are proposed, and the patterns of influence of the ligand nature on dissociation kinetics were determined. The Pd(II) complexes proved to be much more stable than other those of the other metals, according to the results of the kinetic studies. The lability of the complexes strongly depends on the length and position of the alkyl substituent of the ligand. The dissociation of the Ni(II) complex gives a heteroligand complex at low concentrations of acid, but the complex undergoes full protolytic dissociation at higher concentrations of acid. The dissociation of the complex of Cu(II) is an equilibrium process, involving formation of the protonated form of the ligand.
- Rumyantsev, Evgeniy V.,Marfin, Yuriy S.
-
p. 699 - 704
(2014/08/18)
-
- Ni(II) complex extended structures sustained by hydrogen bonding, φ-φ and C-HφInteractions
-
The complex [Ni(NAA)2 (im)6](1) (where H 2NAA = α-naphthylacetic acid and im = imidazole) has been synthesized under solvothermal conditions. The complex fully characterized by IR spectroscopy, elemental analysis and single crystal X-ray diffraction. In complex 1, Ni(II) is coordinated by six N atoms with a octahedral coordination geometry. This mononuclear complex is further extended into threedimensional structure via φ-φ, C-Hφand hydrogen bonding interactions. The thermal stable property of complex 1 is also reported.
- Zhang, Zhen-Ming,Yin, Fu-Jun,Zhao, Gui,Wang, Li-Ping,Zhao, Hong
-
p. 814 - 816
(2014/06/09)
-
- Reduction and hydrogenation of a diazene by a (β-diketiminato)nickel hydrazide
-
A (β-diketiminato)nickel(II) hydrazido(1-) complex [L tBuNi-(η2-N2H3)], {1, L tBu = [HC(CtBuNC6H3{iPr}2) 2]-} has been obtained by treatment of [LtBuNiBr] with hydrazine. In a reaction of 1 with two equivalents of the azo compound diisopropyl azodicarboxylic ester (adc-OiPr) the Ni(N2H3) entity acts as both a hydrogenating and a reducing agent: diisopropyl hydrazidodicarboxylate (hdc-OiPr) is formed, and more adc-OiPr is reduced by two electrons. The resulting (adc-OiPr)2- is found as a ligand in the ultimate nickel product complex, the trinuclear nickel(II) compound [L tBuNi(μ-adc-OiPr)Ni(μ-adc-OiPr)NiLtBu] (2), in which two LtBuNi+ units are linked by a [NiII(adc- OiPr)2]2- moiety. The hypothesis that L tBuNiI species are acting as intermediates was supported by the independent finding that 2 can also be obtained by reaction of [L tBuNi(OEt2)] with adc-OiPr.
- Koethe, Claudia,Metzinger, Ramona,Limberg, Christian
-
p. 3937 - 3942
(2013/11/06)
-
- Kinetic stability of complexes of some d-metals with 3,3'- bis(dipyrrolylmethene) in the binary proton-donor solvent acetic acid-benzene
-
The kinetics of dissociation of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) binuclear homoleptic double-stranded helicates with bis(2,4,7,8,9- pentametyldipyrrolylmethen-3-yl)methane (H2L) of the [M 2L2] composition
- Antina,Guseva,V'yugin,Antina
-
p. 1293 - 1297
(2013/01/14)
-
- Thermo-Raman spectroscopy in situ monitoring study of solid-state synthesis of NiO-Al2O3 nanoparticles and its characterization
-
Hyphenation of thermogravimetric analyzer (TGA) and thermo-Raman spectrophotometer for in situ monitoring of solid-state reaction in oxygen atmosphere forming NiO-Al2O3 catalyst nanoparticles is investigated. In situ thermo-Raman spe
- Ghule, Anil Vithal,Ghule, Kalyani,Tzing, Shin-Hwa,Punde, Tushar H.,Chang, Hua,Ling, Yong Chien
-
p. 3406 - 3411
(2010/03/25)
-
- Magnetostructural correlations in heteroleptic nickel(II) complexes
-
Heteroleptic nickel(II) complexes with the general formula Ni(L)m(H2O)n(X)k, have been synthesized and structurally characterized; L stands for neutral N-donor ligands: 4-benzofuropyridine (bzfupy), dimethylfuro
- Titi?,Bo?a,Dlha?n?, L'.,?ur?eková,Fuess,Ivaniková,Mrázová,Papánková,Svoboda
-
p. 1523 - 1530
(2008/10/09)
-
- Heteroleptic nickel(II) complexes formed from N-donor bases, carboxylic acids and water: Magnetostructural correlations
-
Nickel(II) complexes with the general formula [Ni(L1)2(L2)2(H2O)2], where L1 = 2-methylimidazole (Meiz), 1,2-dimethylimidazole (Me2iz), iso-quinoline (iqu) and 4-furopyridine (fupy), L2 = formate and acetate, have been prepared and characterized. The structures of four complexes [Ni(Meiz)2(HCOO)2(H2O)2] (1), [Ni(Me2iz)2(HCOO)2(H2O)2] (2), [Ni(iqu)2(CH3COO)2(H2O)2] (3) and [Ni(fupy)2(CH3COO)2(H2O)2] (4) were determined by X-ray diffraction methods. The chromophore of these compounds, {NiO2 O2′ N2}, is formed by four oxygen atoms and two nitrogen atoms. The structures of complexes 2, 3 and 4 are formed by two-dimensional networks which consist of individual molecules linked together by O-H?O hydrogen bonds from carboxylate groups to aqua ligands. In complex 1, the formation of a three-dimensional network is supplemented by N-H?O, hydrogen bonds from the coordinated oxygen atom to the secondary nitrogen atom of an imidazole molecule from another unit. All complexes show magnetic behavior typical for zero-field splitting systems. The axial parameter of the zero-field splitting, D, adopts moderate-negative values and it correlates with the axial distortion of the coordination polyhedron.
- Ivaniková,Bo?a,Dlháň,Fuess,Ma?lejová,Mrázová,Svoboda,Titi?
-
p. 3261 - 3268
(2008/10/09)
-
- Racemic and chiral expanded salen-type complexes derived from biphenol and binaphthol: Salbip and salbin
-
The reaction of 2-fluoronitrobenzene with 2,2′-biphenol or (R)-binaphthol, followed by reduction and subsequent reaction of the resulting diamine with two equivalents of a salicylaldehyde, affords expanded salen-type ligands having backbones based on biphenol or binaphthol: salbipH2, (R)-salbinH2 and (R)-salbin(t-Bu)4H2. Deprotonation of these ligands with sodium methoxide or potassium hydride, followed by metallation with M(OAc)2 (M = Mn, Co, Ni, or Cu), affords the corresponding metal complexes in good yield (61-85%). The species containing Mn, Co, and Ni all have distorted octahedral geometry, as determined by X-ray crystallography. The ethereal oxygen atoms occupy two coordination sites with metal-oxygen distances ranging from 2.19 to 2.36 ?. The imine nitrogen atoms are trans to each other in the solid state, an impossible geometry in traditional salen-type complexes. The species containing Cu are distorted square planar and show much longer metal-ethereal oxygen distances ranging from 2.79 to 3.22 ?. The manganese complexes are competent catalysts for the epoxidation of olefins.
- Grill, Joseph M.,Reibenspies, Joseph H.,Miller, Stephen A.
-
p. 3009 - 3017
(2007/10/03)
-
- Kinetics of the Dissociation of Transition Metal Complexes with α,α-Dipyrrolylmethene in Acetic Acid-Benzene as a Binary Proton-Donating Solvent
-
The kinetics of the dissociation of Co(II), Ni(II), and Zn(II) complexes with 4,4′-dibutyl-3,3′,5,5′-tetramethyldipyrrol-2,2′- ylmethene was studied in acetic acid-benzene as a binary proton-donating solvent. The metal nature was found to affect the kinetic parameters of the process. Assumptions were made about the limiting step of the process and the effectiveness of d metal ions in the template synthesis of porphyrins from dipyrrolylmethenes.
- Guseva,Antina,Berezin
-
p. 690 - 693
(2008/10/08)
-
- Study of nickel-cobalt alloy electrodeposition from a sulfamate electrolyte with different anion additives
-
The experimental results of the present study show that the composition of the electrodeposited nickel-cobalt alloy in sulfamate electrolytes containing anion additives is influenced in a complicated manner by the concentrations of cobalt(II) ion and citric acid, pH, and applied current density. The operating conditions were found under which the increase in the pH of the solution adjacent to the cathode is inhibited. Citrate anions form a wide variety of complexes with nickel and cobalt. Protonated citrate complexes of nickel(II) and cobalt(II) are apt to be involved in the electrochemical alloying process. Acetate anions serve to buffer the sulfamate solutions. Nickel-cobalt electrochemical alloying leads to an increase in the reaction rate of cobalt at the expense of the nickel reaction rate. The data confirm that inhibition of the more noble metal by the less noble one does not depend on the anion composition of the electrolyte.
- Golodnitsky,Gudin,Volyanuk
-
p. 4156 - 4163
(2008/10/08)
-
- Thermochemical reactivity of transition metal acetates and of a novel DMSO solvate of iron(II) acetate in molecular hydrogen
-
The thermal decomposition of acetates of the transition metals Fe, Co, Ni, Mn and Cu in molecular hydrogen has been investigated by means of combined thermogravimetry/mass spectrometry, X-ray diffraction, and transmission as well as scanning electron microscopy. In the context of the reproducible preparation of the parent phases, i.e. the hydrated or anhydrous metal(II) acetates, single crystalline Fe3(CH3COO)6(DMSO)2, a novel DMSO solvate of iron(II) acetate, has been isolated and its crystal structure has been determined by means of X-ray diffraction. For the series of metal(II) acetates it has been found that the course of the thermal degradation in molecular hydrogen, in particular the formation of the gaseous products, strongly depends on the transition metal ion present in the parent compound. The detailed characterization of the solid products revealed, that phases exhibiting different catalytic activities and selectivities are formed as micro- or nanocrystalline metals and/or metal oxides.
- Ehrensberger,Schmalle,Oswald,Reller
-
p. 139 - 149
(2008/10/09)
-
- A thermochemical study of the reaction of salicylaldoxime with anhydrous nickel(II) and cobalt(II) acetate
-
The solid-state coordination reaction: 2HSAO(s) + Ni(Ac)2(s) → Ni(SAO)2(s) + 2HAc(g) 2HSAO(s) + Co(Ac)2 · 4H2O(s) → Co(SAO)2 · 2H2O(s) + 2HAc(g) + 2H2O(g) have been studied by classical solution calorimetry. The molar dissolution enthalpies of the reactants and the products in a certain solvent (for one reaction is in 6 mol 1-1 HCl and another in a mixed solution consisting of DMSO and DMF) of this two solid-solid coordination reactions have been measured using an isoperibol calorimeter. From the results and other auxiliary quantities, the standard molar formation enthalpies of [Co(SAO)2·2H2O, s, 298.2 K] and [Ni(SAO)2, s, 298.2 K] at 298.2 K have been determined to be ΔfΗm [Co(SAO)2·2H2O, s, 298.2 K] = -957.205 kJ mol-1 and ΔfΗm [Ni(SAO)2, s, 298.2 K] = -403.336 kJ mol-1.
- Songsheng, Qu,Ying, Feng,Ruili, Yang,Liangchao, Li
-
-
- Kinetics of complexation of heavy metal ions with polyelectrolytes in aqueous solation
-
The kinetics of the binding of Ni2+ to polycar'ooxylate anions have been studied using pressure- and temperature-jump relaxation techniques. The reaction proceeds via the two-step Eigen mechanims: free ions form the outer-sphere and in the second step the inner-sphere complex. The outer-sphere complex is exceptionally stable due to the polyelectrolyte effect, and the electrical potential at the polyelectrolyte surface is estimated to be ψ = - 86 mV. The rate constant for the formation of the inner-sphere complex is in the same range as that obtained for Ni2+ complexes with smail anions. The formation of bidentate complexes does not contribute significantly to the stability of the complexes. A parallel study of the reactions of Ni2+ with malonate and succinate has been performed. VCH Verlagsgesellschaft mbH, 1996.
- Hermeier, Imke,Herzig, Matthias,Knoehe, Wilhelm,Pohimeier, Andreas,Narres, Hans-Dieter
-
p. 788 - 795
(2007/10/03)
-
- Solid State Reactions of Dimethylglyoxime with Nickel Acetate at Close to Room Temperature
-
Solid state reactions of dimethylglyoxime (H2DMG) with both nickel acetate tetrahydrate and anhydrous nickel acetate result in the formation of Ni(HDMG)2 at room temperature. Electrical conductivity measurements havebeen used to study the two kinetic processes, for which we have calcula ted the activation energies of 26.9 and 33.5 kJ.mol**-1, respectively. The difference of reactivity is discussed in terms of structural characteristics and presence of crystal water.
- Zheng, Li-Min,Zhang, Wei-Hua,Yao, Xue-Bin,Xin, Xin-Quan
-
p. 1091 - 1100
(2008/10/09)
-
- Hydrogenation process
-
Process for the hydrogenation of functionally substituted acetylenic compounds employing catalyst comprising nickel boride on an inorganic oxide support is disclosed. Functionally-substituted acetylenic compounds are selectively reduced under mild reaction conditions to give functionally-substituted cis-olefinic compounds in high yield.
- -
-
-
- Interaction of Nickel(0) Complexes with Allyl Carboxylates, Allyl Ethers, Allylic Alcohols, and Vinyl Acetate. ?-Complex Formation and Oxidative Addition to Nickel Involving Cleavage of the Alkenyl-Oxygen Bond
-
Interaction of various allylic compounds with bis(1,5-cyclooctadiene)nickel, Ni(cod)2, in the absence and presence of tertiary phosphines, causes cleavage of allyl-oxygen bonds.Allyl acetate reacts with Ni(cod)2 to afford a mixture of Ni(η3-C3H5)2 and Ni(OCOCH3)2 presumably through an intermediate, allylnickel acetate, followed by its disproportionation.Similar reactions in the presence of tertiary phosphine ligands, PR3 (triphenylphosphine (PPh3), ethyldiphenylphosphine (PEtPh2), tricyclohexylphosphine (P-c-Hx3)), give Ni(η3-C3H5(OCOCH3)(PR3) (1-3).Allyl formate can be catalytically converted into propylene and CO2 at 25 deg C by a Ni(cod)2-PPh3 mixture.A reaction of allyl phenyl ether with a mixture of Ni(cod)2 and PPh3 at 30 deg C also leads to cleavage of the C-O bond to yield Ni(η3-C3H5)(OC6H5)(PPh3) (4).Complexes 1-4 react with morpholine to produce N-allylmorpholine in 65-82percent yields.On the other hand, similar reactions of diallyl ether with mixtures of Ni(cod)2 and phosphine ligands do not cause C-O bond cleavage under mild conditions and yield complexes formulated as Ni(?-diallyl ether)(PR3) (PR3 = PPh3, P-c-Hx3) (5 and 6).Allylic alcohols RCH=CHCH2OH (R = H, CH3, C6H5) are dismutated into RCH=CHCH3, RCH=CHCHO, and H2O on interaction with mixtures of Ni(cod)2 and phosphines at 30-50 deg C.The mixture of Ni(cod)2 and PPh3 serves as a catalyst for the allylation of morpholine by allyl alcohol.The C-O bond in vinyl acetate is also cleaved on interaction with Ni(cod)2 alone or mixtures of Ni(cod)2 and phosphines.Complexes 1-6 are characterized by elemental analysis and spectroscopy (IR and NMR).As for the mechanism of the C-O bond-cleavage reaction of allyl-oxygen compounds, one involving coordination of the allylic compound to Ni through the C=C double bond followed by a bond rearrangement involving C-O bond cleavage is proposed.
- Yamamoto, Takakazu,Ishizu, Junichi,Yamamoto, Akio
-
p. 6863 - 6869
(2007/10/02)
-
- FURTHER INVESTIGATIONS ON THE OXIDATION REACTION DERIVATIVES OF BISBENZAMIDOXIMATONICKEL(II). STRUCTURAL CHARACTERIZATION OF BENZAMIDOXIMATO-N1-OXY-N2-BENZOYLIMINODIAZENATONICKEL(II)
-
The nature of the red nickel compound 1, obtained by reacting a basic solution of nickel(II) salts with benzamidoxime, PhC(=NOH)NH2, in the presence of dioxygen or by addition of hydrogen peroxide, has been reconsidered.When boiled in acetone or alcohols, 1 gives place to a deep violet derivative 2 whose molecular structure has been determined by three-dimensional single-crystal X-ray diffraction analysis.Crystals are tetragonal, space group I41/a, with a=b=20.294(4), c=14.720(4) Angstroem, Z=16.The nickel atom is four-coordinated in a square planar manner, and lies at the common apex of two coplanar pentaatomic rings formed by two different bidentate (chelating) monoanionic ligands.One of these is a N,O-coordinated benzamidoximato moiety, , the other the new species .When 1 is boiled in benzene, a new red violet compound 3 is isolated.This is considered a tautomeric form of the deep violet derivative 2.It reacts with benzamidoxime in mild conditions giving back the starting complex 1, which is formulated as a 1:1 adduct of 3 with the benzamidoxime molecule.Compound 3 converts into derivative 2 in boiling acetone or alcohols.The reactions of 1 and 2 with acids and their oxidising power towards iodide solutions have been further investigated and extended to 3.The probable mechanism by wich these nickel complexes are formed is discussed.
- Malatesta, Lamberto,Monica, Girolamo La,Manasero, Mario,Sansoni, Mirella
-
p. 113 - 122
(2007/10/02)
-
- Metal hydrates and salts of carboxylic acids
-
A metal salt of a carboxylic acid is formed by contacting a carboxylic acid with an activated metal. The activated metal is formed by combining a first metal with a second metal which has an affinity for hydrogen in the presence of a proton source. Typically, an activated aluminum is formed from a highly pure aluminum rod combined with an alloy of indium and gallium in the presence of hydrochloric acid. The addition of excess water in the presence of the carboxylic acid and activated metals forms a polymeric metal salt from a water soluble carboxylic acid.
- -
-
-
- Cobalt and nickel acetates in anhydrous acetic acid
-
Both cobalt and nickel acetates form hemisolvates with acetic acid. Both of these compounds exhibit retrograde solubility in anhydrous acetic acid between 16 and 65°, solubility equilibrium being attained very slowly. From ternary mixtures of cobalt aceta
- Tappmeyer,Davidson, Arthur W.
-
p. 823 - 825
(2008/10/08)
-