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1.
Reduction of various pentafluorophenylnickel(II) complexes in the presence of phosphines gives unstable nickel(I) compounds but Ni(C6F5)(CO)2(PPh3)2 is isolated in the presence of CO. Similar NiR(CO)2(PPh3)2 (R = C6F5,C6Cl5, 2,3,5,6-C6Cl4H) are obtained by reaction of the halogenonickel(I) complex with MgRBr or LiR. Reduction of NiX2L2 in the presence of acetylenes gives [NiXL2]2(μ-PhCCR) (R = H, X = Cl and R = Ph, X = Cl, Br) when L = P-n-Bu3 but only NiX(PPh3)3 are recovered when L = PPh3. No reaction with the alkyne is observed for [NiX(PPh3)2]n but [NiCl(PPh3)]n reacts with RCCR′ to give paramagnetic NiCl(PPh3)(CRCR′) (R = Ph, R′= H, COOEt), diamagnetic [NiCl(PPh3)]2(μ-PhCCPh) and cyclotrimerization when R = R′ = COOMe. Chemical and structural behaviour of the new nickel(I) complexes is described.  相似文献   

2.
Summary The tetrahedral compounds [Co(SC6F5)2L] (L=Ph2P(CH2) n PPh2,n=1, 2 and 3) and the squareplanar compound [Ni(SC6F5)2(PhPCH2CH2PPh2)] have been obtained by mathematical reactions of [MX2L] (M=Co or Ni, X=Cl or Br) and Pb(SC6F5)2. The reaction of pentacoordinate [CoCl(Ph2PCH2CH2PPh2)2]+ and the lead salt yields [CoCl2L] and [Co(SC6F5)2L]. Magnetic moments, u.v. data (both in solution and solid state) and the crystal and molecular structure of the nickel compound are reported.  相似文献   

3.
Benzyl Nickel(II) Complexes and their Reactions By the oxydative addition of p-substituted benzyl chlorides to (Ph3P)2Ni(C2H4) at ?20°C the violet nickel(II) complexes (Ph3P)2Ni(p-CH2C6H4R)Cl (R ? CN, COOH, CH3, Cl) are, formed. In water containing solutions the carbonic acid (Ph3P)2Ni(p-CH2C6H4COOH)Cl is rearranged to the corresponding p-methylbenzoate. With carbon dioxide the complexes (Ph3P)2Ni(p? CH2C6H4R)Cl react like Grignard compounds. Diphenyl ethine and butadien-1,3 are inserted in the Ni—C bond at room temperature. Substituted nickel-σ-vinyl or π-allyl complexes are obtained. The reactivity of the nickel-σ-benzyl compounds is compared with that of other nickel(II)-alkyl compounds.  相似文献   

4.
Cationic nickel(II) complexes containing chelating O,O′-donor maltolate or ethyl maltolate ligands in conjunction with bidentate bisphosphine ligands Ph2P(CH2) n PPh2 were prepared by a one-pot reaction starting from nickel(II) acetate, bisphosphine, maltol (or ethyl maltol), and trimethylamine, and isolated as their tetraphenylborate salts. An X-ray structure determination of [Ni(maltolate)(Ph2PCH2CH2PPh2)]BPh4 shows that the maltolate ligand binds asymmetrically to the (slightly distorted) square-planar nickel(II) center. The simplicity of the synthetic method was extended to the synthesis of the known platinum(II) maltolate complex [Pt(maltolate)(PPh3)2]BPh4 which was obtained in high purity.  相似文献   

5.
Bis(diphenylphosphano)alkane- and 1-Diphenylphosphano-2-(2-pyridino)ethane-N-arylsulfinylamine Nickel(0) Complexes Synthesis and properties of the bis(diphenylphosphano)alkane-N-phenyl-sulfinylamine-nickel(0) complexes [Ni{Ph2P(CH2)nPPh2}(PhNSO)] (n = 2 dppe, n = 3 dppp, n = 4 dppb) as well as of the 1-(diphenylphosphano)-2-(2-pyridino)ethane nickel(0) complexes [Ni(dpppe)2], [Ni(dpppe)(p-TolNSO)] and [Ni(dpppe)(PPh3)2] are described. These compounds have been characterized by i. r. and 31P n.m.r. spectroscopy. The N-arylsulfinylamine ligands are η2-(N, S)-side on coordinated.  相似文献   

6.
Summary The reduction of nickel(II) halides with NaBH4 in the presence of different ligands, L=PPh3, AsPh3, SbPh3, has been studied. With a molar ratio L/Ni=3, new complexes NiX(SbPh3)3, X=Cl, Br, I, were obtained. With a molar ratio L/Ni=2, dimeric species [NiXL2]2, X=Cl, Br, I; L=PPh3, AsPh3, SbPh3, were isolated. They are unstable and decompose easily in the solid and rapidly in solution, so that pure samples were only identified for X=Cl, L=PPh3, AsPh3, SbPh3; X=Br, L=PPh3 and X=I, L=PPh3. With a molar ratio L/Ni=1, complexes [NiXL]n (probably polymeric) were obtained. They are very unstable and pure samples could only be isolated when X=Cl, L=PPh3. Impure substances containing variable amounts of decomposition products were obtained in all the remaining cases. The chemical and structural behaviour of these complexes is discussed.  相似文献   

7.
The neutral complexes (η5-C5H5NiXL (X = Cl, L = PPh3 (I); L = PCy3 (II); X = Br, L = PPh3 (III); L = PCy3 (IV); X = I, L = PPh3 (V); L = PCy3 (VI)) have been obtained by treating NiX2L2 with thallium cyclopentadienide. The same reaction in the presence of TlBF4 gives cationic derivatives [(η5-C5H5)NiL2]BF4 (L = 2PPh2Me (VII); L = dppe (VIII)), whereas mononuclear complexes containing two different ligands (L2 = PPh3 + PCy3 (IX)) or dinuclear [(η5-C5H5)Ni(PPh3)]2dppe(BF4)2 (X) are obtained from the reaction of III with TlBF4 in the presence of a different ligand. Reduction of cationic complexes with Na/Hg gives very unstable nickel(I) derivatives (η5-C5H5)NiL2, which could not be isolated purely. Similar reduction of neutral complexes under CO gives a mixture of decomposition products containing [(η5-C5H5)Ni(CO)]2 and nickel(o) carbonyls, whereas in the presence of acetylenes, dinuclear [(η5-C5H5)Ni]2(RCCR′) (R = R′ = Ph; R = Ph, R′ = H) are obtained.  相似文献   

8.
Oxidation of Mixed Ligand Nickel(0) Complexes by Organic Halides The oxidation of (dipy)Ni(PPh3)2 by alkyl and aryl iodides or bromides affords the nickel(I) complexes (dipy)Ni(PPh3)X (X = Br, I). No normal products of oxidative addition are obtained. But in the case of methyl and ethyl halides complexes of the type (dipy)NiR2 are formed as intermediates. Basing on the identified final products and on the correalation between the reactivity of the organic halides and their polarographic half wave potentials a mechanism of the reaction is proposed. The first step is a charge transfer from nickel(0) to the organic halide. Further synthesis, reactions, and the ESR-spectra of the complexes (dipy)Ni(PPh3)X and a synthesis of (dipy)Ni(CH2Ph)2 are described. Experiments to prepare pure (dipy)Ni(PPh3)Cl had no success.  相似文献   

9.
Ni(II) di(pentyl)dithiocarbamates of composition [Ni(Pe2dtc)2], [NiX(Pe2dtc)(PPh3)] (X = Cl, Br, I, NCS), [Ni(NCS)(Pe2dtc)(PBut3)], [Ni(Pe2dtc)(PPh3)2]ClO4 and [Ni(Pe2dtc)(PPh3)2]PF6 (Pe2dtc = di(pentyl)dithio-carbamate, PPh3 = triphenylphosphine, PBut3 = tributylphosphine) have been synthesized. The complexes have been characterized by the usual methods. X-ray structure analyses confirmed the nature of [NiI(Pe2dtc)(PPh3)] and [Ni(Pe2dtc)(PPh3)2]ClO4 complexes.  相似文献   

10.
Summary Rhodium(I), iridium(I), palladium(II) and platinum(II) complexes of the phosphinoamide ligands, Ph2PCH2CONHR (R = H, HDPA; Me, MDPA; Ph, PDPA) were prepared and characterized by using conductivity data, i.r., 1H and 31P(H) n.m.r. spectral data. Reaction of the ligands with MCl(PPh3)3 and MCl(CO)(PPh3)2 (M = Rh, Ir) in CH2Cl2 under reflux lead to the formation of MCl(PPh3)2 [Ph2PCH2C(O)NHR] and MCl(CO)(PPh3)[Ph2PCH2–C(O)HNR] respectively. The reaction of either K2MCl4 or cis-MCl2(PPh3)2 affords complexes of the type cis-MCl2[Ph2PCH2C(O)NHR]2 (M = Pd, Pt). A similar product results even from the reaction of phosphinoamides with cis-platin. Possible structures are proposed for the complexes based on their physicochemical data  相似文献   

11.
Preparation and properties of nickel(II) and cobalt(II) chelates of the bidentate ligand trans-2-ethylthio-cyclohexyl-phenylphosphine (ÄMCPP) are described. Three types of nickel(II) complexes have been obtained from ÄMCPP: the four-coordinated, square planar [Ni(ÄMCPP)2]X2 (X = J, Br, ClO4); five-coordinated [Ni(ÄMCPP)2X]X (X = Cl, NCS), [Ni(ÄMCPP)2X]BPh4 (X = Cl, NCS) and the octahedral [Ni(ÄMCPP)2Cl2]. Cobalt(II) forms tetrahedral 1.1-[Co(ÄMCPP)X2] (X = Br, Cl) and 1.2-Co(ÄMCPP)2X2(X = Br, Cl, NCS) complexes. All compounds were characterized by electronic reflectance and absorption spectra, conductivity and magnetic measurements.  相似文献   

12.
Compounds of the type [XM(CO)2(ν-allyl)L2] (where X = Cl and Br; M = Mo and W; L2 = Ph2PCH2PPh2 and Ph2 PCH2CH2PPh2) have been prepard from the corersponding MeCN complexes. The spectral properties of these compounds and the effects of chelate rign size on 31P coordination shifts and J(183W—31P) have been investigated.  相似文献   

13.
The reaction of the lithium salt of backbone fluorinated β‐diketiminate ligands, ArNC(CF3)CHC(CF3) NArLi, with trans‐[NiCl(Ph)(PPh3)2] gives nickel (II) complexes, ArNC(CF3)CHC(CF3)NAr(Ph) (PPh3)Ni (Ar = 2, 6‐Me2C6H3: 1 ; 2, 6‐iPr2C6H3: 2 ). When activated by methylaluminoxane (MAO), both complexes polymerize norbornene rapidly via a vinyl‐type polymerization mechanism. Treatment of nickel complex 1 with oxygen gives rise to intramolecular aerobic hydroxylation. The oxygenated species 3 was characterized by X‐ray crystallography. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

14.
Complexes with Macrocyclic Ligands. IV. Heterodinuclear Cobalt(II), Nickel(II), Copper(II), Zinc(II) and Palladium(II) Complexes with a Macrocyclic Ligand of Schiff‐Base Type: Syntheses and Structures The synthesis and properties of nickel(II), copper(II), and palladium(II) complexes, [MLPh] ( 3 ; LPh = N,N′‐phenylene‐bis(3‐formyl‐5‐tert.‐butyl‐salicylaldimine)), are described. These neutral mononuclear complexes react with metal(II) perchlorate and 1,3‐propylenediamine to form heterodinuclear, macrocyclic, cationic complexes of the type [MM′(LPh,3)]2+ ( 4 ; M = Ni, Cu, Pd; M′ = Co, Cu, Zn). The structures of the five new compounds [NiCo(LPh,3)](ClO4)2, [NiCu(LPh,3)](ClO4)2, [CuCu(LPh,3)](ClO4)2, [CuZn(LPh,3)](ClO4)2, and [PdCu(LPh,3)](ClO4)2 were determined by X‐ray diffraction.  相似文献   

15.
Sulfur Dioxide as Ligand and Synthon. XIII. Reactions of Isocyanide-tris(triphenylphosphane)nickel(0) Complexes with Sulfur Dioxide and N-p-tolylsulfinylamine Reactions of the isocyanide-tris(triphenylphosphane)-nickel(0) complexes [(RNC)Ni(PPh3)3] (R = tBu, Cy, PhCH2, p-TosCH2) with SO2 and p-TolNSO are described. The sulfur dioxide and N-p-tolylsulfinylamine complexes obtained by PPh3 ligand substitution have been characterized by means of i.r. and 31P n.m.r. spectra. The X-ray crystal structure of [(Ph3P)2(CyNC)Ni(SO2)] · 0.5 PhMe and (Ph3P)(tBuNC)Ni(η2-p-TolNSO) have been determined.  相似文献   

16.
Planar nickel(II) complexes involving N‐(2‐Hydroxyethyl)‐N‐methyldithiocarbamate, such as [NiX(nmedtc)(PPh3)] (X = Cl, NCS; PPh3 = triphenylphosphine), and [Ni(nmedtc)(P‐P)]ClO4(P‐P = 1,1‐bis(diphenylphosphino)methane(dppm); 1,3‐bis(diphenylphosphino)propane (1,3‐dppp); 1,4‐bis(diphenylphosphino)butane(1,4‐dppb) have been synthesized. The complexes have been characterized by elemental analyses, IR and electronic spectroscopies. The increased νC–N value in all the complexes is due to the mesomeric drift of electrons from the dithiocarbamate ligands to the metal atom. Single crystal X‐ray structure of [Ni(nmedtc)(1,3‐dppp)]ClO4·H2O is reported. In the present 1,3‐dppp chelate, the P–Ni–P angle is higher than that found in 1,2‐bis(diphenylphosphino)ethane‐nickel chelates and lower than 1,4‐bis(diphenylphosphino)butane‐nickel chelates, as a result of presence of the flexible propyl back bone connecting the two phosphorus atoms of the complex.  相似文献   

17.
Summary The reduction of nickel(II) halides with NaBH4 in ethanol has been studied in the presence of various tertiary phosphines and arsines. Complexes of the type XNiL3 have been isolated in this way when X = Cl, Br, I and L = PPh3, AsPh3, no reaction being observed when L = PEt3, PBu3 and Ph2P(CH2)2PPh2.The reaction of XNiL3 with CO gas at room temperature produces pentacoordinate carbonyl complexes XNi(CO)2L2 when L is triphenylphosphine. The lack of stability prevents the isolation of similar complexes when L is trip henylarsine.Structural data obtained by i.r. spectroscopy and susceptibility measurements as well as chemical behaviour of the new complexes are described.  相似文献   

18.
Abstract

The synthesis and characterization of the complexes [NiCl(SeAr)(DPPE)] (1) and [Ni(SeAr)2(DPPE)] (2) (where Ar = C6H5 (a), 4-MeOC6H4 (b) or 4-EtOC6H4 (c), and DPPE = 1,2-bis(diphenylphosphino)-ethane) is reported. Characterization of the compounds was based on elemental analysis, molecular weight and conductivity measurements, IR, electronic, 1H and 31P NMR spectra. Available evidence supports a square planar environment around Ni(II) in 1 and 2. Metathetical reaction between 1b and NaX (X = Br (d) or I (e)) in MeOH gives [NiX(SeAr)(DPPE)] (3). Electrochemical studies of 1 and 2 using cyclic voltammetry indicate an irreversible cathodic peak (ca ?0.56 to ?0.70 V) corresponding to reduction of nickel(II) to nickel (O).  相似文献   

19.
The nickel(II) N‐benzyl‐N‐methyldithiocarbamato (BzMedtc) complexes [Ni(BzMedtc)(PPh3)Cl] ( 1 ), [Ni(BzMedtc)(PPh3)Br] ( 2 ), [Ni(BzMedtc)(PPh3)I] ( 3 ), and [Ni(BzMedtc)(PPh3)(NCS)] ( 4 ) were synthesized using the reaction of [Ni(BzMedtc)2] and [NiX2(PPh3)2] (X = Cl, Br, I and NCS). Subsequently, complex 1 was used for the preparation of [Ni(BzMedtc)(PPh3)2]ClO4 ( 5 ), [Ni(BzMedtc)(PPh3)2]BPh4 ( 6 ), and [Ni(BzMedtc)(PPh3)2]PF6 ( 7 ). The obtained complexes 1 – 7 were characterized by elemental analysis, thermal analysis and spectroscopic methods (IR, UV/Vis, 31P{1H} NMR). The results of the magnetochemical and molar conductivity measurements proved the complexes as diamagnetic non‐electrolytes ( 1 – 4 ) or 1:1 electrolytes ( 5 – 7 ). The molecular structures of 4 and 5· H2O were determined by a single‐crystal X‐ray analysis. In all cases, the NiII atom is tetracoordinated in a distorted square‐planar arrangement with the S2PX, and S2P2 donor set, respectively. The catalytic influence of selected complexes 1 , 3 , 5 , and 6 on graphite oxidation was studied. The results clearly indicated that the presence of the products of thermal degradation processes of the mentioned complexes has impact on the course of graphite oxidation. A decrease in the oxidation start temperatures by about 60–100 °C was observed in the cases of all the tested complexes in comparison with pure graphite.  相似文献   

20.
A series of square-planar nickel(II) hexamethylenedithiocarbamate complexes with heterogeneous coordination spheres of composition [NiX(hmidtc)Y] · nCHCl3 [X = Cl, Br, I or NCS; hmi = C6H12, dtc = S2CN; Y = PPh3 or PBu3, n = 0,1] have been synthesized and characterized by elemental analyses, i.r. and u.v.–v.i.s. spectroscopy, magnetochemical and conductivity measurements, and by thermal analysis. X-ray structures of [NiCl(hmidtc)(PPh3)] · CHCl3 and [NiBr(hmidtc)(PPh3)] · CHCl3 have been determined.  相似文献   

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