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1.
Ahmad Saeed Isab Anvarhusein A. Perzanowski Herman P. Hussain M. Sakhawat Akhtar M. Naseem 《Transition Metal Chemistry》2002,27(2):177-183
Phosphine sulfides and their gold(I) complexes with general formula R3P=S—Au—X (X = Cl–, Br– or CN–) were prepared and characterized by elemental analyses, i.r. and 31P-n.m.r. spectroscopy. A decrease in the i.r. frequency of the P=S bond in the ligands upon complexation, is indicative of S coordination to gold (I). The 31P-n.m.r. spectra revealed that electronegativity of the substituents and angles between them were the two most important factors influencing the 31P-n.m.r. chemical shifts. The phosphorus resonance was observed to be more downfield in alkyl substituted phosphine sulfides as compared to the aryl substituted phosphine sulfides. Ligand scrambling in the Cy3P=S—Au—CN complex in solution, to form [(Cy3P=S)2Au]+ and [Au(CN)2]–, was investigated by 13C and 15N-n.m.r. spectroscopy. Equilibrium constants (K
eq) for scrambling of the Cy3P=S—Au—CN complex and for its analogue, Cy3P=Se—Au—CN were measured by integrating the 13C-n.m.r. at 297 K and were found to be 0.147 and 1.81 respectively. 相似文献
2.
《Journal of Coordination Chemistry》2012,65(5):391-398
Three mixed ligand complexes of gold(I) with phosphines and selenones, [Et3PAuSe=C<]Br as analogues of auranofin (Et3PAuSR) have been prepared and characterized by elemental analysis, IR and NMR methods. A decrease in the IR frequency of the C=Se mode of selenones upon complexation is indicative of selenone binding to gold(I) via a selenone group. An upfield shift in 13C NMR for the C=Se resonance of the selenones and downfield shifts in 31P NMR for the R3P moiety are consistent with the selenium coordination to gold(I). 13C solid state NMR shows the chemical shift difference between free and bound selenone to gold(I) for ImSe and DiazSe to be ca 10 and 17?ppm respectively. Large 77Se NMR chemical shifts (55?ppm) upon complexation in the solid state for [Et3PAuDiazSe]Br compared to [Et3PAuImSe]Br (10?ppm) indicates the former to be more stable and the Au–Se bond to be stronger than in the latter complex. 相似文献
3.
《Journal of Coordination Chemistry》2012,65(21):3824-3832
A series of aurocyanide and auricyanide complexes of phosphines, phosphine sulfides, and phosphine selenides were synthesized. These new complexes have the general formula [L n Au(CN) m ], where L could be Cy3P, (2-CN-Et)3P, Me3PS, Et3PS, Ph3PS, Me3PSe, or Ph3PSe. Auricyanide was reacted with L at 1?:?2 ratio. Products were characterized using elemental analysis, melting point, UV, IR, far-IR solution, and solid-state NMR spectroscopy. Phosphine ligands cause gold(III) reduction to gold(I); less redox tendency was found for phosphine sulfides and phosphine selenides. Tri-coordinate complexes [L2AuCN] were produced from phosphine ligands with gold-tetracyanide. IR and UV spectroscopic methods were used to identify gold oxidation state in the synthesized complexes. 相似文献
4.
《Journal of Coordination Chemistry》2012,65(9):1541-1549
New cadmium(II) complexes with phosphine telluride ligands of the type CdX2(R3PTe)n [X?=?ClO4?, n?=?4: R?=?n-Bu (1), Me2?N (2), C5H10?N (3), C4H8?N (4) or OC4H8?N (5); X?=?Cl–, n?=?2: R?=?n-Bu (6), Me2?N (7), C5H10?N (8), C4H8?N (9) or OC4H8?N (10)] have been synthesized and characterized by elemental analyses, IR and multinuclear (31P, 125Te, and 113Cd) NMR spectroscopy. In particular, the solution structures of these complexes were confirmed by 113Cd NMR at low temperature, which displays a quintuplet for each of the perchlorate complexes and a triplet for each of the chloride complexes due to coupling with four and two equivalent phosphorus atoms, respectively, indicating a four-coordinate tetrahedral geometry for the metal center. These multiplet features were further accompanied by one bond Te–Cd couplings, clearly showing that the ligand is coordinated to the metal through tellurium. The results are discussed and compared with those obtained for closely related phosphine chalcogenide analogs. 相似文献
5.
Cyclic α, β-Unsaturated Carbonyl Compounds as Ligands in Nickel (0) Complexes . As a result of the reaction of (Cy3P)2Ni(C2H4) with p-benzoquinone (p-CH) or maleic anhydride (MSA), nickel(II)-complexes of radical anions are formed which are derived from PCy3 and p-CH or MSA by an equimolecular coupling. With other cyclic α, β-unsaturated carbonyl compounds (L = 1,4-naphthoquinone, substituted α- and γ-pyrones, substituted coumarins) no comparable reactions proceed in the coordination sphere of nickel(0) phosphine complexes. But depending on the phosphine and on the substrate compounds of the types (R3P)2NiL or (R3P)NiL are obtained. Taking the substituted coumarins for an example, it was demonstrated that the latter type is favoured by bulky phosphines (PCy3) and by coumarins with a high π-acceptor strength. The i.r. spectra of the complexes (R3P)NiL are in accordance with an η3(C?C,O)-bridging function of α, β-unsaturated carbonyl ligands and therefore with an oligomeric structure. For the complexes (R3P)2NiL and (dipy)NiL an η2(C?C) or a pseudo-η3 (C?C,C) coordination of the ligands is discussed. Of special interest are the compounds (Cy3P)Ni(DMP) and (Cy3P)Ni(BDH) (DMP = 2, 6-dimethyl-γ-pyrone, BDH = 2-benzylidene-1, 3-dioxo-hydrindene). Possibly the substituted γ-pyrone is an η6-ligand in (Cy3,P)Ni(DMP). (Cy3,P)Ni(BDH) is considered to be a nickel(II) chelate of a diva-lent anion which is derived from BDH by the uptake of two electrons. In this connection the limits for a classification of the new complexes as nickel(0) or nickel(II) compounds are mentioned. The polarographic half-wave potentials are applied to an estimation of the reactivity of the α, β-unsaturated carbonyl compounds related to nickel(0) complexes. 相似文献
6.
《Journal of Coordination Chemistry》2012,65(5):766-778
Three new propanedithiolate-type iron–sulfur complexes containing tris(aromatic)phosphine ligands, [{(μ-SCH2)2CH2}Fe2(CO)5L] (L?=?P(PhOMe-p)3, 1; P(PhMe-p)3, 2; P(PhF-p)3, 3), have been prepared through carbonyl substitution in the presence of Me3NO. The new complexes 1–3 were characterized by elemental analysis, IR, 1H, 13C{1H}, and 31P{H} NMR spectra. The molecular structures of 1–3 were unequivocally determined by single crystal X-ray diffraction, in which the tris(aromatic)phosphine coordinated to Fe resides in an apical position of the pseudo-square-pyramidal geometry. IR spectroscopy and X-ray crystallographic analysis for 1–3 have indicated that the highly electron rich tris(aromatic)phosphine ligands (where the corresponding electron-donating abilities display the following order of P(PhOMe-p)3?>?P(PhMe-p)3?>?P(PhF-p)3) result in a considerable red shift of the CO-stretching frequencies and a clear change of the Fe–Fe bond distances in 1–3. 相似文献
7.
(dipy)Ni(COD) react with duroquinone (Dch) or anthraquinone (Ach) to yield the complexes (dipy)Ni(η4 -Dch) or (dipy)Ni(η4 -Ach). Chloranil (CA), however, reacts as an oxidant and depending on the temperature (dipy)NiII(CA2-) or following an oxidative addition (dipy)NiII(Cl)(CAH-)(THF) are formed.By substitution of (Cy3P)2Ni(C2H4) the complexes (Cy3P)Ni(η4-Dch) or (Cy3P)2Ni(η4 -Ach) are obtained, whereas a 1,1-coupling of quinone and the coordinated phosphine proceeds during the reaction between p-benzoquinone of chloranil and (Cy3P)2Ni(C2H4). By ESR studies it was demonstrated that with Ni(Cy3P?Ch)2 or Ni(Cy3P?CA)2, resp., complexes are obtained, in which radical anions, which are derived from the product of this 1,1-coupling, are coordinated to low-spin nickel (II). There is a significant difference between (Cy3P)2Ni(C2H4) and the analogous platinum or palladium complexes, which are substituted by p-benzoquinone while an oxidative addition proceeds with chloranil. 相似文献
8.
M. T. Ben Dhia M. A. M. K. Sanhoury C. Zenati M. R. Khaddar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):3082-3089
The complexes CdL4(ClO4)2 (1), CdL2(NO3)2 (2), and CdL2Cl2 (3) (L = (Me2N)3P(Se)) have been prepared and characterized by elemental analysis, conductivity measurements, IR, and multinuclear (31P, 77Se, and 113Cd) NMR spectroscopy. 31P and 77Se NMR data were informative of changes associated with complex formation. The structure of the prepared complexes was further confirmed in solution by their 113Cd NMR spectra, which show a quintuplet for the perchlorate complex and a triplet for each of the nitrate and chloride complexes due, respectively, to coupling with four and two equivalent phosphorus atoms, consistent with a four coordinate tetrahedral geometry for the cadmium center. The NMR data are discussed and compared with those reported for related complexes. 相似文献
9.
《Journal of Coordination Chemistry》2012,65(7):1076-1085
Planar [Ni(bedtc)(PPh3)Cl] (1), [Ni(bedtc)(PPh3)(NCO)] (2), [Ni(bedtc)(PPh3)(NCS)] (3), [Ni(bedtc)(PPh3)(CN)] (4) and [Ni(bedtc)(dppe)]ClO4 (5) (where bedtc = N-benzyl-N-(2-hydroxyethyl)dithiocarbamate anion, PPh3 = triphenylphosphine and dppe = 1,2-bis((diphenylphosphino)ethane)) were prepared from [Ni(bedtc)2]. Complexes 1–5 were characterized by elemental analysis, electronic, IR and NMR (1H, 13C, and 31P) spectra. Electronic spectra of the complexes show bands corresponding to dz 2 → dxy/dx 2 ? y 2 transitions. The complexes were diamagnetic. IR and 13C NMR studies indicate the mesomeric flow of π-electron density from the dithiocarbamate towards the nickel. In 1H NMR, α-CH2–and β-CH2–protons of–CH2–CH2–OH were equally deshielded. The deshielding for the coordinated phosphorus signals in 31P NMR spectra for all the cases compared with the free phosphine clearly manifests the drift of electron density from the phosphorus toward the metal on complexation. Single crystal X-ray structures of 1–3 indicate that nickel is in a planar environment with short >S2C–N bond distances. In 2, a rare mode of coordination between nickel and cyanate (NCO?) through the nitrogen is observed. Significant asymmetry in Ni–S bond distances were observed for 1–3 clearly supporting the trans influences of Cl?, NCO? and NCS?, respectively, over PPh3. 相似文献
10.
Nana Kim Prof. Ross A. Widenhoefer 《Angewandte Chemie (International ed. in English)》2018,57(17):4722-4726
Methoxide abstraction from gold acetylide complexes of the form (L)Au[η1‐C≡CC(OMe)ArAr′] (L=IPr, P(tBu)2(ortho‐biphenyl); Ar/Ar′=C6H4X where X=H, Cl, Me, OMe) with trimethylsilyl trifluoromethanesulfonate (TMSOTf) at ?78 °C resulted in the formation of the corresponding cationic gold diarylallenylidene complexes [(L)Au=C=C=CArAr′]+ OTf? in ≥85±5 % yield according to 1H NMR analysis. 13C NMR and IR spectroscopic analysis of these complexes established the arene‐dependent delocalization of positive charge on both the C1 and C3 allenylidene carbon atoms. The diphenylallenylidene complex [(IPr)Au=C=C=CPh2]+ OTf? reacted with heteroatom nucleophiles at the allenylidene C1 and/or C3 carbon atom. 相似文献
11.
0 IntroductionIn recent years, silver carboxylates have attractedmany interests, mostly because they are promisingcandidates in the growth of metal thin films via metal-organic chemical vapor deposition (MOCVD) tech-niques. These sliver compounds show low light sensi-tivity and relatively high thermal stability. Several ex-amples of bisphosphine ligands coordinated silver car-boxlylates have been reported[1 ̄4].Monophosphine coordinated silver complexes areexpected to have better volatility,… 相似文献
12.
Timothy J. Brown Dr. Atsushi Sugie Dr. Marina G. D. Leed Prof. Ross A. Widenhoefer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(22):6959-6971
A family of seven cationic gold complexes that contain both an alkyl substituted π‐allene ligand and an electron‐rich, sterically hindered supporting ligand was isolated in >90 % yield and characterized by spectroscopy and, in three cases, by X‐ray crystallography. Solution‐phase and solid‐state analysis of these complexes established preferential binding of gold to the less substituted C?C bond of the allene and to the allene π face trans to the substituent on the uncomplexed allenyl C?C bond. Kinetic analysis of intermolecular allene exchange established two‐term rate laws of the form rate=k1[complex]+k2[complex][allene] consistent with allene‐independent and allene‐dependent exchange pathways with energy barriers of ΔG≠1=17.4–18.8 and ΔG≠2=15.2–17.6 kcal mol?1, respectively. Variable temperature (VT) NMR analysis revealed fluxional behavior consistent with facile (ΔG≠=8.9–11.4 kcal mol?1) intramolecular exchange of the allene π faces through η1‐allene transition states and/or intermediates that retain a staggered arrangement of the allene substituents. VT NMR/spin saturation transfer analysis of [{P(tBu)2o‐binaphthyl}Au(η2‐4,5‐nonadiene) ]+SbF6? ( 5 ), which contains elements of chirality in both the phosphine and allene ligands, revealed no epimerization of the allene ligand below the threshold for intermolecular allene exchange (ΔG≠298K=17.4 kcal mol?1), which ruled out the participation of a η1‐allylic cation species in the low‐energy π‐face exchange process for this complex. 相似文献
13.
Zied Gouid R. Ben Said Cameron L. Carpenter-Warren Alexandra M. Z. Slawin M. T. Ben Dhia 《Journal of Coordination Chemistry》2017,70(23):3859-3870
Four new zinc(II) complexes of the type [ZnCl2(n-Bu3PE)2] (E=O (1), S (2), Se (3), or Te (4)) have been synthesized from zinc(II) chloride and the ligands n-Bu3PE giving yields of 56–88%. The adducts were characterized by multinuclear (31P, 13C, and 77Se) NMR, conductivity, IR spectroscopy and by X-ray analyses. Zinc complexes 1–4 are compriseS of two ligands coordinated to the metal center in a distorted tetrahedral arrangement. The P=E bond lengths of 1.497(7) (E=O), 2.000(4) (E=S), and 2.178(2) Å (E=Se) in these complexes are slightly elongated compared to those in the free ligand. In addition, a DFT/B3LYP theoretical study on the geometry optimization of the title ligands and their zinc complexes has been carried out in order to support and complement the experimental data and to further investigate the nature of the chalcogenide-metal interaction. The results show good agreement between the experimental and theoretical data. 相似文献
14.
Gordon Bulloch Rodney Keat David S. Rycroft David G. Thompson 《Magnetic resonance in chemistry : MRC》1979,12(12):708-712
The 1H and 31P NMR spectra of a series of compounds containing the PIII-N-PV skeleton including Cl2PNMeP(Z)Cl2 (Z?O or S), Cl2P·NMe·P(O)CINMe2, P4(NMe)6Zn (Z?S, n = 1?3; Z?Se, n = 1), XP(NBut)2P(Z)X (X?Cl, Z?O or S; X?OMe, Z?S or Se; X?NMe2, Z?S or Se; X?NEt2, Z?Se), (X?O or S), and Ph2PNRP(S)Ph2 (R?Me, Et) have been obtained. 1H-{31P} double resonance, and in selected cases, 31P-{1H, 77Se} and 31P-{1H, 31P} triple resonance experiments, indicate that 2J(PIII NPV) is positive in acyclic compounds, negative in most cyclic or cage compounds, and furthermore, is related to the conformation adopted by the PIII-N bond. 相似文献
15.
Masami Nakamoto Huub Koijman Martin Paul Wolfgang Hiller Hubert Schmidbaur 《无机化学与普通化学杂志》1993,619(8):1341-1346
The reaction of 1,2- and 1,3-benzenedithiol C6H4(SH)2 with chloro(phosphine)gold(I) complexes R3PAuCl (R = Et, Ph) in the presence of triethylamine in tetrahydrofuran gives stable gold(I) complexes 1,2-C6H4(SAuPR3)2 [R = Et ( 1 ) and Ph ( 2 )] or 1,3-C6H4(SAuPPh3)2 ( 3 ), respectively, in high yield. The compounds have been characterized by analytical and NMR spectroscopic data. From the reaction of 1,2-C6H(SH)2 with Et3P? AuCl a by-product [(Et3P)2Au]+ [Au(1,2? C6H4S2)2]? ( 4 ) has also been isolated in low yield. The crystal structures of compounds 2 and 4 have been determined by single crystal X-ray diffraction. The gold(I) atoms in complex 2 are two-coordinate with bond angles S? Au? P of 175.2(1) and 159.5(1)°, Au? S bond distances of 2.304(1) and 2.321(1) å, and a short Au…?Au contact of 3.145(1) Å. The gold(I) atom in the cation of complex 4 is also linearly two-coordinate with a P? Au? P angle of 170.1(1) Å and Au? P distances of 2.296(3) and 2.298(3) Å. The geometry of the anion in 4 shows a square-planar coordination of gold(III) by two chelating 1,2-benzenedithiolate ligands with Au? S distances between 2.299(3) and 2.312(3) Å (for two crystallographically independent, centrosymmetrical anions in the unit cell). 相似文献
16.
Meriem Bennis Khaled Alouani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1490-1497
Abstract Five new complexes ZnL2(ClO4)2 (1), CdL2(ClO4)2 (2), CdL2(BF4)2 (3), CdLCl2 (4), and CdL(NO3)2 (5) [L = ((Me2N)2PSe)2NMe] have been synthesized and characterized by elemental analysis, infrared (IR) and multinuclear (31P, 77Se, and 113Cd), and nuclear magnetic resonance (NMR) spectroscopy. The 31P and 77Se NMR data showed that the title ligand is coordinated in a bidentate fashion to the metal center via its both P=Se groups. The solution structure of the cadmium complexes was further confirmed by its 113Cd NMR spectra, which displayed a quintuplet for the perchlorate complex and a triplet for each of the nitrate and chloride complexes, respectively due to coupling with four (two ligands) and two (one ligand) equivalent phosphorus nuclei, consistent with a four-coordinate tetrahedral geometry for the cadmium center. The results are discussed and compared with the corresponding oxo and thio analogues. 相似文献
17.
《Journal of Coordination Chemistry》2012,65(2):227-242
Four new substituted amino acid ligands, N-(3-hydroxybenzyl)-glycine acid (HL1), N-(3-hydroxybenzyl)-alanine acid (HL2), N-(3-hydroxybenzyl)-phenylalanine acid (HL3), and N-(3-hydroxybenzyl)-leucine acid (HL4), were synthesized and characterized on the basis of 1H NMR, IR, ESI-MS, and elemental analyses. The crystal structures of their copper(II) complexes [Cu(L1)2]·2H2O (1), [Cu(L2)2(H2O)] (2), [Cu(L3)2(CH3OH)] (3), and [Cu(L4)2(H2O)]·H2O (4) were determined by X-ray diffraction analysis. The ligands coordinate with copper(II) through secondary amine and carboxylate in all complexes. In 2, 3, and 4, additional water or methanol coordinates, completing a distorted tetragonal pyramidal coordination geometry around copper. Fluorescence titration spectra, electronic absorption titration spectra, and EB displacement indicate that all the complexes bind to CT-DNA. Intrinsic binding constants of the copper(II) complexes with CT-DNA are 1.32?×?106?M?1, 4.32?×?105?M?1, 5.00?×?105?M?1, and 5.70?×?104?M?1 for 1, 2, 3, and 4, respectively. Antioxidant activities of the compounds have been investigated by spectrophotometric measurements. The results show that the Cu(II) complexes have similar superoxide dismutase activity to that of native Cu, Zn-SOD. 相似文献
18.
Iron Dicarbonyl Complexes Featuring Bipyridine‐Based PNN Pincer Ligands with Short Interpyridine CC Bond Lengths: Innocent or Non‐Innocent Ligand?
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Dr. Thomas Zell Dr. Petr Milko Kathlyn L. Fillman Dr. Yael Diskin‐Posner Dr. Tatyana Bendikov Dr. Mark A. Iron Dr. Gregory Leitus Yehoshoa Ben‐David Prof. Michael L. Neidig Prof. David Milstein 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(15):4403-4413
19.
Abbas Tarassoli Ziba Khodamoradpur 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):712-718
The substitution reaction of bis(anilino)phosphine oxide (C 6 H 5 NH) 2 P(O)H (1) with trans-PtCl 2 (SEt 2 ) 2 yields the novel unprecedented phosph(V)azane-platinum complex cis-Pt(SEt 2 ) 2 Cl[HNPhP(O)NPh(HNEt 3 )] (3). In this reaction, the bis(anilino)phosphine oxide undergoes P–H activation and a Pt(II)–P(V) bond instead of Pt–N bond forms. 31 P NMR spectra readily distinguish between the “N” and “P” bonding modes. The reaction requires the presence of triethylamine (TEA) as a base in order to deprotonate the phosphazane ligand and is separated as Et 3 NH+Cl?, whereas HTEA+ exists in the final product 3 and is acting as charge balancing and H-bond structure directing agent. The products have been fully characterized by means of IR; MS; UV-Vis; and 1 H, 13 C, and 31 P NMR spectroscopy. 相似文献
20.
《Journal of Coordination Chemistry》2012,65(8):1434-1442
Reactions between [Pd(C2,N-dmba)(μ-X)]2 (Hdmba?=?N,N-dimethylbenzylamine; X?=?Cl, Br, NCO, N3) and 1,3-bis(4-pyridyl)propane (bpp) in 1?:?1 molar ratio at room temperature resulted in the binuclear compounds [{Pd(C2,N-dmba)(X)}2(μ-bpp)] (X?=?Cl (1), Br (2), NCO (3), N3 (4)), which were characterized by elemental analyses, infrared (IR), 1H- and 13C{1H}-NMR spectroscopies, and thermogravimetric analysis. The IR and NMR data of 1–4 were consistent with the presence of bridging bpp. The thermal stability order of the complexes was 4?>?3?>?2?>?1. Compounds 1–4 and bpp were tested against Mycobacterium tuberculosis and their MIC values were determined. 相似文献