Nickel pyridinethiolate complexes as catalysts for the light-driven production of hydrogen from aqueous solutions in noble-metal-free systems J Am Chem Soc . The phosphinitooxazoline 4,4-dimethyl-2-[1-oxy(diphenylphosphine)-1-methylethyl]-4,5-dihydrooxazole (9), the corresponding phosphinitopyridine ligands 2-ethyl-[1'-methyl-1'-oxy(diphenylphosphino)]pyridine (11) and 2-ethyl-6-methyl-[1'-methyl-1'-oxy(diphenylphosphino)]pyridine (12), which have a one-carbon spacer between the phosphinite oxygen and the heterocycle, and the homologous . The most common stoichiometries found in nickel (H) pyridine and substituted pyridine complexes are NiX2L4 and NiX2L2 where X is a mononegative ion and L is pyridine or a substituted pyridine. These ligands readily form the palladium and nickel complexes upon treatment with (COD)PdMeCl and (DME)NiBr2, respectively. Abstract (pyrazolylmethyl)pyridine nickel(II) & iron(II) complexes' is my original work that was carried out in the Discipline of Chemistry, School of Chemistry & Physics of the College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Pietermaritzburg Campus, South Africa. The complex has been characterized by spectral technique and thin-layer chromatography method. [Pg.76] ligand in 1) have been explored with considerable depth.2,3 In particular, the imidazole-derived ligands, A survey of NiII complexes involving pyridine-3-carbonitrile as ligand led us to some other related structures. The Ni complex can give a TONcat up to 1340 in the homogeneous photocatalytic system. Synthesis and structure of nickel 2-methyl-5-propylthio-8-hydroxyquinolinate - pyridine adduct Ni[C{sub 9}H{sub 4}(CH{sub 3})(SC{sub 3}H{sub 7})NO]{sub 2}(C{sub 5}H{sub 5}N){sub 2}; Kompleksy nikelya (II) s 8-oksikhinolinom i 8-merkaptokhinolinom. Complexes 3-6 were single crystals. X-ray and UV photoelectron-spectroscopic studies of pyridine adsorbed on evaporated nickel and palladium in the temperature range 140-385 k. Besides, promoting the photo-generated electrons transfer from . New PCN Py pincer nickel complexes have been synthesized through a short synthetic route. Now, a nickel-aluminium pincer complex offers new mechanistic insight into transmetalation, and new potential for reactivity. The lower valent pyridine complexes of these metals are composed of carbonyl and nitrosyl counterpart. The CO stretch of the nickel-bound carbon monoxide ligand of [pyrr2py]Ni(CO) has been observed at 2101 cm1. Ni(bpy)3Cl2 was firstly found to be an active material for photocatalytic CO2 reduction. Pyridine-functionalized Ni-NHC complexes have been prepared and characterized by various methods. 2013 Oct 2;135(39):14659-69. doi: 10.1021/ja405257s. Copper(II) complex gave a value of magnetic moment 1.74 BM . Cyclic voltammograms of compounds 1 - 3 and 5 in MeCN. the nickel catalyst. Your request will be reviewed and you will receive an email when it's processed. Abstract Chloro (pyridine)cobaloxime. Abstract We report a homologous series of nickel ( II) complexes supported by N -heterocyclic carbene - pyridine ( R bimpy, R = Me, Et, Pr) ligands that exhibit high selectivity for reducing carbon dioxide over water under electrocatalytic conditions. Complexes 1 and 2 are racemic, namely, each molecule has a chiral center of or , thereby forming NO-trans- and - geometries in the solid state. Sampl e solutions that were 5 x 10-4 r-. The formation of such an intermediate with NaAD would enhance the reactivity of C5 to facilitate carboxylation. Experiment 2.1. CiteSeerX - Document Details (Isaac Councill, Lee Giles, Pradeep Teregowda): R factor = 0.081; wR factor = 0.321; data-to-parameter ratio = 13.7. Crabtree's catalyst. The color of nitromethane solutions of this square-planar complex turns from red to cyan, purple, blue, yellow-green, and pink following addition of halides, acetonitrile, water, pyridine, and 2,2'-bipyridine, respectively. the acid site of the catalyst was analyzed by pyridine infrared before and after the . NICKEL(II) PINCER COMPLEXES SUPPORTED BY 2,6-BIS(3,5-DITOLYL-2-PYRROLYL)PYRIDINE by ABHIJIT PRAMANIK . . Formation constants for metal complexes of Cu(II), Ni(II), and Ag(I) with some substituted pyridine ligands were determined in a nitrate salt solution of the ligand (0.5 F KNO3 + 0.1 F HL) at 25 C The phosphorus substituents in these bidentates are 2-tolyl, 2-anisyl, and mesityl. The complex having the most planar coordination geometry appeared to have the highest catalytic efficiency for proton reduction in DMF ( ic / ip = 50, kobs = 490 s -1 at 0.1 V/s) using acetic acid as the proton source. The flask was warmed until all the green solid has dissolved and a white solid has formed. No nickel pyridine dipyrrolide complexes have been reported thus far. Materials and Methods All the chemicals used were of analytical reagent grade. All complexes have octahedral Ni(II) center(s) and were magnetic. Hitoshi Miyasaka, Sachie Furukawa, . Complexes of pyridine and its derivatives are a cornerstone to diverse chemical reactions. of plane bending of C-H of pyridine ring appeared at 705-764 cm-1.21 CH 2 rocking and Cu-N stretching vibration mode of ethylenediamine were appeared about 850-950 cm-1 and 500-610 cm-1, respectively for both complexes.21 The IR spectrum of complex2 shows NH stretching at 3366 cm-1 and a band at 3056 cm-1 attributed to the symmetric stretch 9. The Ni complex is also an active electrocatalyst for reduction of protons. Pyridine also enhanced the stability of -hydrogen-containing alkyl . (2018) investigated the ability of pyridine . Molar magnetic moment and exchange energy of nickel(II) complex with pyridine-substituted nitronyl nitroxide radical measured using SQUID method is given in this chapter. Read "Nickel and iron complexes with oxazoline- or pyridine-phosphonite ligands; synthesis, structure and application for the catalytic oligomerisation of ethylene, Dalton Transactions" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. (II) complexes. The Ni(II) complex has a magnetic moment located in the range 3.20 BM. Complexes of formula NipysX2 have been found to correspond to either [NiX2py4]-2py (X = NCS, NCO)818 or [Ni (N03)2py3]-3py.819. . Introduction of the redox processes on structural rearrangements of nickel complexes.8 In this work, besides the effect of the pH on the Macrocyclic polyamines, like cyclen or cyclam, bearing co- coordination of a pyridine pendant arm on complexes of ordinating pendant arms have attracted a lot of attention1 cyclen- and cyclam-pyridine . Reduction to the nickel ( I) state provided access to an unusual nickel ( I) fluoride complex stabilized by H-bonds, enabling structural and spectroscopic characterization. Each Ni II atom is coordinated by two O and four N atoms . Graphene-encapsulated nickel nanoclusters are a feasible strategy to inhibit the nickel deactivation of nickel-based catalysts. Heine et al. tetradentate ligand in the equatorial plane and one coordinat- all complexes are air and moisture stable in the solid The title nickel complexes showed comparable activities with 8-arylimino-5,6,7-trihydroquinolyl nickel analogues; whilst both exhibited higher activities than did the 2-iminopyridyl nickel analogue due to the enhancement of the ring-tension of cyclic-fused pyridine derivatives. Nickel (II) complexes of the above bases with nitrate, glycollate and lactate as anion have also been isolated. Pyridine also enhanced the stability of -hydrogen-containing alkyl . Sodium thiocyanate (0.601g) was dissolved in Ethanol (11cm3), to this nickel nitrate hexahydrate (0.773g) was added. Thus their preparation is carried out in a neutral atmosphere. Title Pyridine adduct of nickel(II) complex with 1-(3-hydroxy-2-naphthyl)-5-(phenyl)pent-4-ene-1,3-dione Book Title Magnetic Properties of Paramagnetic Compounds Perhaps the most closely related compounds are the four-coordinate platinum (VIWSIF; Komine et al., 2014), palladium (XIKKIO, XIKKOU; Yadav et al., 2018) and zinc (VIWSIF; Komine et al., 2014) complexes featuring all-nitrogen coordination spheres at the metal. This result is consistent with DMAP being a more strongly donating ligand than unsubstituted pyridine. Although several nickel SCS pincer complexes have previously been reported (8-10), none exhibited an essential feature present in the active site of lactate racemase, namely a pyridinium-based pincer backbone.According to the proposed enzyme mechanism, the pyridinium group enables ligand participation in the hydride transfer reaction, which is likely impossible for a more conventional . These were then reacted with nickel(II) salts to form Ni[NNN]X2 complexes. Complexes with cyclam as co-ligand were more thermally stable than those with pyridine and its derivative, L. Complexes 3 and 4 were mesomorphic after partial loss of 2 Introduction Within the diverse field of N-heterocyclic carbene metal complexes,1 ligand systems involving a 'pincer' binding geometry with a range of donor groups have been extensively studied.2,3,4 As a subset, CNC 'pincer' ligands based on pyridine with pendant NHC donors (e.g. The pyrrolyl pyridine pincer ligand, a relatively new class of dianionic, tridentate, nitrogen-based ligands in coordination chemistry, was prepared starting with a modified method for the synthesis of pyrrolyl pyridine. Read "'Pincer' pyridine dicarbene complexes of nickel and their derivatives. 1972, 50, 1307-1314. As foretelled for a high spin d 8 system with two unpaired electrons which falls in the range expected for octahedral Ni(II) compounds . J. Chem. A nickel pyridine-selenolate complex is an efficient photocatalyst for H 2 generation. Silina, E, Bankovsky, Yu, Pech, L, Ashaks, J, and Belsky, V. Nickel (II) complexes with 8-hydroxyquinoline and 8-mercaptoquinoline. The newly synthesized nickel [NiIILN2PY3]2+ complex was catalytic and showed better stability during the electro/photocatalytic water reduction, compared to the first three nickel complexes. 50 Organometallic Complexes of Phosphinopyridines and Related Ligands h2pydco (isocinchomeronic acid or pyridine2,5dicarboxylic acid n-oxide) is an appropriate candidate for constructing new metal organic compounds through covalent bonds with metal ions as well as. The CO binding constants range from 1.3 x 10{sup 2} to 2.8 x 10{sup 5} M{sup -1} at 25 {degrees}C in acetonitrile. The asymmetric unit of the crystal structure of the title complex, [Ni(C18H12N2O3)(C5H5N)3] 3C5H5N, contains two independent Ni II complex molecules and six uncoordinated pyridine molecules. D. C. Patel; R. C. Sharma; P. K. Bhattacharya. From the obtained band positions the ligand . pyridylmethyleneaminomethyl)pyridine(StructureI),which contains the -N=GC=N-G-G=N-group,and to investigate theirstereochemistrybymeans of magnetic,spectraland The extended aromatic system of pyridine-like ligands influences considerably the molecular structure of prepared nickel complexes. The properties of Ni(II) complexes, Ni(I) complexes, and Ni(I)-CO complexes with a series of 14-membered macrocyclic N{sub 4} ligands were studied by means of UV-vis, NMR, and IR spectroscopy. Nickel( ) complexes with L2a-L2c, when treated with an excess of NaCN, liberated macrocyclic ligands that could be isolated by extraction in chloroform or methylene chloride followed by solvent evaporation. comp lex ions formed by Ni(II) ion and pyridine compounds. A facile heterogeneous photocatalyst system that consists of a nickel complex and cadmium sulfide (CdS), which act as the catalyst and light antenna, respectively, was developed to the efficiency photocatalytic activation and conversion of CO2. The field strengths of (1a) and (1b) are found to be marginally less than those of the isomeric ligands 2,6-di(thiazol-4-yl)pyridine (2a) and 2,6-di(2-methylthiazol-4-yl . Achieving the transition metal-catalysed pyridine C3H alkenylation, with pyridine as the limiting reagent, has remained a long-standing challenge. The reduction products of a series of divalent (pyrox)Ni complexes establish the redox activity of pyrox in stabilizing electron-rich Ni(II)-alkyl and -aryl complexes by adopting a ligand-centered radical . which may well serve as a standard for complexes Bis-(2-pyridinaldoxime)-nickel(II), [Ni(POX)2], which are uni-univalent electrolytes in methanol. Adduct of his oxine nickel with pyridine, -and -picoline have been prepared. Unlike their Schi base pre- cursors, these ligands were stable towards hydrolysis and could be used to prepare complexes of other metals. The new nickel (II) complex has also been screened for antibacterial and antifungal activities against various pathogenic bacteria and fungi. The nickel complexes are four-coordinate and adopt a square-planar geometry. New pyridine-phosphine ligands of general structure 2-[2-(diarylphosphino)ethyl]pyridine were developed. Pyridine fused with a furan ring (fupy), and its dimethyl derivative, have been used for the first time as ligands to synthesize potentially new Werner clathrates. The ligands could be conveniently synthesized in good yields. This book is the In this system, HZSM-5 was a micron molecular . Previously, we disclosed that the use of . Spectrophotometric titrations of [Ni (L)] (BF4)2 were performed with neutral and negatively charged ligands. Effect of donor atom (ether vs. thioether) on coordination geometry, spin-state of cobalt and M(III)-M(II) redox potential. The higher valent rhenium accommodates oxo ligands along with anionic monodentate and chelating ligands. Comparisons of thermodynamics and ligand-fieldparameters show that dmso is a much weaker ligand compared with pyridine than could be predicted from previous experi- ( 5 mmol) corresponding to complexes 11, 12 and 14 prepared m e n t ~ . Once cooled the solution was filtered under suction and the Filtrate (aqua blue liquid in Buchner flask) was added to the refluxing . The complexes were identified using NMR spectroscopy, superconducting quantum interference device (SQUID), and X-ray crystallography. The synthesis and characterization of a mononuclear nickel(II) complex [Ni(L2)](ClO4)2 (1) and an analogous mononuclear copper(II) complex [Cu(L2)](ClO4)2 (2) of a 15-membered azamacrocycle (L2 = 3-(2-pyridyl)-6,8,8,13,13,15-hexamethyl-1,2,4,5,9,12-hexaazacyclopentadeca-5,15-diene) are reported. The structural studies revealed that complexes 1 and 2 have similar . The nickel(II) complex is the easiest to reduce in the series, with E 1/2 = 0.9 V. Figure 7. To arrive at the top five similar articles we use a word-weighted algorithm to compare words from the Title and Abstract of each citation. Pyridine Adsorption and Acid/Base Complex Formation on Ultrathin Films of -Al2O3 on NiAl(100). Nickel(II) dichloride complexes with a pyridine-chelated imidazo[1,5-a]pyridin-3-ylidene py-ImPy ligand were developed as novel catalyst precursors for acrylate synthesis reaction from ethylene and carbon dioxide (CO2), a highly promising sustainable process in terms of carbon capture and utilization (CCU). Owing to the relatively wide C-N-C angle, the 2,6-hydrogen atoms interfere with the formation of [M (py) 6] z complexes. Two types of ImPy salts were prepared as new C,N-bidentate ligand precursors; py-ImPy . the nickel ion in complex 1a is coordinated from 1a and 2a via anion exchange by adding a solution of the in a square-pyramidal geometry, with the donor atoms of the complex in methanol to a boiling methanol solution of nh4pf6. View This Abstract Online; Cobalt(II), nickel(II) and copper(II) complexes of a hexadentate pyridine amide ligand. This compound displays pyridine in this complex is retained tenaciously; a molar conductivity (in methanol) of 89.7 ohms-' drying in vacuo over Pz06causes no apparent loss. Incorporating pyridine as the nitrogen side arm facilitated the C-H activation in the PCN ligand and allowed the cyclometallation with nickel to take place at room temperature. Studies in Some Nickel (ll) Complexes. Reactions at the azomethine C N bonds in the nickel(II) andcopper(II) complexes of pyridine-containing Schi-basemacrocyclic ligands Aida M. Herrera,a Ganna V. Kalayda,a Jeremy S. Disch,a Jerey P. Wikstrom,a Ivan V. Korendovych,a Richard J. Staples,b Charles F. Campana,c Alexander Y. Nazarenko,d Terry E. Haasa and Elena V. Rybak-Akimova*a a Department of Chemistry, Tufts University . Bromochlorotetrakis(pyridine)nickel(II) has been prepared and characterized by means of elemental analysis, infrared spectra, conductance measurements and electronic spectra.