Elucidation of the structures of the hydridothiolato complexes WH(SC6H2Pri3-2,4,6)3(L)(PMe2Ph), L = PMe2Ph or pyridine, by NMR and X-ray techniques

1995 ◽  
Vol 73 (7) ◽  
pp. 1092-1101 ◽  
Author(s):  
Timothy E. Burrow ◽  
Alan J. Lough ◽  
Robert H. Morris ◽  
Raymond L. Richards
Keyword(s):  
X Ray Diffraction ◽  
Pyridine Ligand ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Pyridine Ligands ◽  
Trigonal Bipyramidal ◽  
Hydride Ligand ◽  
Nmr Methods

Measurement of the T1 values of the 31P nuclei in the unusual capped trigonal bipyramidal complexes WH(tipt)3(PMe2Ph)2 (1, tipt = SC6H2Pri3-2,4,6) and W(2H)(tipt)3(PMe2Ph)2 allows the determination of the phosphorus–hydride distance of 2.2 ± 0.2 Å and the P-W-H angle of about 62 ± 7°. An approximate location of the hydride on an S2P face is proposed on the basis of steric interactions. The crystal structure of WH(tipt)3-(NC5H5)(PMe2Ph) (2) is reported; the WS3NP core consists of a distorted trigonal bipyramidal system with the phosphine and pyridine ligands axial and the thiolate ligands equatorial. The hydride ligand was not located by X-ray diffraction but can be positioned on an open S2P face at an angle P-W-H of about 65°. The small P-W-H angle results in large 2J(H,P) couplings for 1 and 2. The 1H NMR spectrum of complex 2 is assigned by use of NOE and homodecoupling NMR methods. This complex has the same crowded structure in solution as in the crystalline state. The pyridine ligand, which is sandwiched between two tipt aryl groups, is hindered from rotating around the W—N bond. Keywords: molybdenum, tungsten, thiolate, hydride, NMR, NOE.

Organometallic oxides: preparation of the cluster [(η-C5Me5)Mo]4O7 by reduction of [(η-C5Me5)MoCl(O)]2(μ-O) or (η-C5Me5)MoCl2(O)

2000 ◽  
Vol 78 (3) ◽  
pp. 383-394
Author(s):  
Frank Bottomley ◽  
Victor Sanchez ◽  
Robert C Thompson ◽  
Olusola O Womiloju ◽  
Zhiqiang Xu
Keyword(s):  
Nmr Spectra ◽  
Chloroform Solution ◽  
X Ray Diffraction ◽  
Broad Resonance ◽  
Nmr Spectrum ◽  
X Ray ◽  
Temperature Range ◽  
H Nmr ◽  
Tributyltin Hydride ◽  
Effective Moment

Reduction of [(η-C5Me5)MoCl(O)]2(μ-O) or (η-C5Me5)MoCl2(O) with sodium or magnesium amalgam, magnesium turnings, or tributyltin hydride produced [(η-C5Me5)Mo]4O7, with [(η-C5Me5)Mo(O)(μ-O)]2 as a co-product. [(η-C5Me5)Mo]4O7 was characterized by X-ray diffraction, mass spectrometry, 1H NMR and IR spectroscopies, and magnetism. Crystals of [(η-C5Me5)Mo]4O7 contained a tetrahedral [(η-C5Me5)Mo]4 unit (Mo-Mo = 2.909 (3) Å) with the Mo4O7 core having the structure Mo4(μ2-O(b))3(µ2-O(c))3(µ3-O(a)) (3). Microcrystalline samples of [(η-C5Me5)Mo]4O7 were paramagnetic over the temperature range 2-300 K, with an effective moment of 1.26 μB at 300 K. [(η-C5Me5)Mo]4O7 was also paramagnetic in chloroform solution, over the temperature range 223-298 K, with an effective moment of 1.43 µB at 298 K. The 1H NMR spectrum showed a broad resonance at 16.3 ppm (Δν 1/2 = 113 Hz) and two narrow resonances at 1.89 ppm and 1.69 ppm (Δν 1/2 = 5 Hz). The magnetism and NMR spectra showed that [(η-C5Me5)Mo]4O7 existed in two forms which were in equilibrium in solution. One form was paramagnetic (S = 1), with the Mo4O7 core having the geometry 3, and the other was diamagnetic (S = 0), with the Mo4O7 core having the geometry 4.Key words: cluster, cyclopentadienyl, molybdenum, oxide, paramagnetism.

Das 7,8-Benzo-5-chloro-1,4,4-trimethyl-1-aza-4-azonia-6,9-dioxa-5 λ5-phosphaspiro[4.4]nonanyl-Kation: Röntgenstrukturanalyse und temperaturabhängige 1H-NMR-Spektren: The 7, 8-Benzo-5-chloro-1,4,4-trimethyl-1-aza-4-azonia-6,9-dioxa-5 λ).5-phosphaspiro[4.4]nonanyl Cation: X-Ray Crystal Structure Determination and Variable 1H NMR Spectra

1992 ◽  
Vol 47 (6) ◽  
pp. 755-759 ◽  
Author(s):  
Thomas Kaukorat ◽  
Peter G. Jones ◽  
Reinhard Schmutzler
Keyword(s):  
Crystal Structure ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Crystal Structure Analysis ◽  
Acceptor Interaction ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Trigonal Bipyramidal ◽  
Donor Acceptor

The 1H NMR spectrum of the spirophosphorane 3 at room temperature indicates dynamic behaviour of the cation. The low-temperature 1H NMR spectra of 3 exhibit two sets of doublets for the protons of the diastereotopic N(CH3)2 groups. The free enthalpy of activation for the dynamic process was determined (58.6 KJ/mole). In the reaction of 3 with sodium tetraphenylborate the crystalline compound, 4, involving the non-coordinating anion, [B(C6H5)4]-, was obtained. The X-ray crystal structure analysis of 4 reveals the presence of a five-membered ring, formally as a result of intramolecular donor-acceptor interaction between the nitrogen atom of the N(CH3)2 group and phosphorus. The geometry at phosphorus deviates somewhat from ideal trigonal bipyramidal.

A bis-Au(III) [28]hexaphyrin triphenylphosphine adduct

2016 ◽  
Vol 20 (08n11) ◽  
pp. 997-1001 ◽  
Author(s):  
Koji Naoda ◽  
Atsuhiro Osuka
Keyword(s):  
Solid State ◽  
Structural Analysis ◽  
Trifluoroacetic Acid ◽  
X Ray Diffraction ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Detailed Structural Analysis ◽  
Nir Absorption ◽  
Plausible Mechanism

Triphenylphosphine was added regioselectively at the C(3) position of bis-Au(III) complex of [26]hexaphyrin 5 in the presence of trifluoroacetic acid to produce [28]hexaphyrin triphenylphosphine adduct 6 in 62% yield, which has been fully characterized by NMR, UV-vis/NIR absorption, and MS spectroscopies, and X-ray diffraction analysis. The rigid planar structure forces 6 to take Hückel antiaromaticity, which has been supported by its 1H NMR spectrum. Curiously, the detailed structural analysis elucidated that the triphenylphosphine moiety exists as a phosphorane form in the solid state. A plausible mechanism via a double protonated 5 is proposed, which can explain the observed regioselectivity.

Darstellung, 11B-, 1H-NMR und Schwingungsspektren von 4-Aminopyridylundecahydro-closo-dodecaborat(1-) sowie Kristallstruktur von (Ph4As)[(4-(NH)-C5H4N)B12H11]·2CH3CN / Synthesis, 11B , 1H NMR and Vibrational Spectra of 4-Aminopyridylundecahydro-closo- dodecaborate(1-) and Crystal Structure of (Ph4As)[(4-(NH)-C5H4N)B12H11]·2CH3CN

1997 ◽  
Vol 52 (8) ◽  
pp. 939-942 ◽  
Author(s):  
T Koch ◽  
W Preetz
Keyword(s):  
1H Nmr ◽  
Deae Cellulose ◽  
Exchange Chromatography ◽  
Orthorhombic Space Group ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Stretching Vibrations ◽  
Ir And Raman

By reaction of (n-Bu4N)2[B12H12] with 4-aminopyridine at 190°C the 4-aminopyridylundecahydro- closo-dodecaborate anion [(4-(NH)-C5H4N)B12H11]- is obtained which can be separated from excess [B12H12]2- by ion exchange chromatography on diethylaminoethyl(DEAE) cellulose. The X-ray structure determination of (Ph4As)[(4-(NH)-C5H4N)B12H11]-2CH3CN (orthorhombic, space group Pbca, a = 14.294(2), b = 19.587(2), c = 27.279(5)Å, Z = 8) reveals that the 4-aminopyridine substituent is bonded via the nitrogen atom of the amino group. The 11B NMR spectrum exhibits the characteristic feature (1:5:5:1) of a monosubstituated B12 cage with a downfield shift of ipso-B1 to -5.4 and antipodal-B12 to -18.1 ppm. The 1H NMR spectrum reveals the pattern of a monosubstituated pyridine. The IR and Raman spectra exhibit characteristic BH stretching vibrations between 2489 and 2521 cm-1 and the CC and CN stretching vibrations in the range of 1405 to 1636 cm-1.

Metallkomplexe von biologisch wichtigen Liganden, CXXIX [1]. Palladium(II)-und Platin(II)-Komplexe von 4,4-disubstituierten Oxazolonen und C2-symmetrischen Bis(oxazolonen) Metal Complexes of Biologically Important Ligands, CXXIX [1]. Palladium(II) and Platinum(II) Complexes of 4,4-Disubstituted Oxazolones and of C2-Symmetric Bis(oxazolones)

2000 ◽  
Vol 55 (10) ◽  
pp. 946-952 ◽  
Author(s):  
Werner Bauer ◽  
Walter Ponikwar ◽  
Wolfgang Beck
Keyword(s):  
Metal Complexes ◽  
Structural Determination ◽  
Palladium Atom ◽  
Chelate Complexes ◽  
Nmr Spectrum ◽  
Methyl Group ◽  
X Ray ◽  
H Nmr ◽  
O 10

Abstract 4-Benzyl-4-methyl-2-phenyl-5(4H)-oxazolone (1) forms with the chloro bridged compounds [R3PMCl2]2 (M = Pt, Pd) the complexes Cl2Pt(PR3)(l) (R = Et, nBu) and Cl2Pd(PEt3)(l). The enantiomeric pure C2-symmetric CMe2 bridged bis(oxazolones) 5 and 6 have also been employed which give with PdCl2 the chelate complexes 13 and 14. The X-ray structural determination of Cl2P d[O-C (O)-CMe2-N=C-CMe2-C=N-CMe2-C (O)-O ] (10) shows that one of the methyl group of the CMe2 bridge is located near the palladium atom. This can also be detected in the 1H NMR spectrum.

scholarly journals M–H–BR3 and M–Br–BR3 interactions in rhodium and nickel complexes of an ambiphilic phosphine–thioether–borane ligand

2018 ◽  
Vol 96 (5) ◽  
pp. 484-491 ◽  
Author(s):  
Bradley E. Cowie ◽  
David J.H. Emslie
Keyword(s):  
Crystal Structure ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Nickel Complexes ◽  
Planar Geometry ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Square Planar ◽  
Hydride Ligand

Reaction of [Rh(μ-Cl)(CO)(TXPB)] (1; TXPB = 2,7-di-tert-butyl-5-diphenylboryl-4-diphenylphosphino-9,9-dimethylthioxanthene) with NaBH4 yielded square planar [Rh(μ-H)(CO)(TXPB)] (2) in which the hydride ligand bridges between rhodium and the borane unit of TXPB. The Rh–H, Rh–B, and Rh–Cipso distances are short at 1.84(5), 2.456(6), and 2.568(5) Å, respectively, whereas the B–H bond, 1.59(6) Å, falls at the longer end of the usual range. Compound 2 is compared with the previously reported series of rhodium TXPB complexes: [RhX(CO)(TXPB)] {X = F (3), Cl (1), Br (4), I (5)}. Compound 4 in this series features the only crystallographically characterized example of an M–Br–BR3 interaction, and to expand this area, [NiBr(μ-Br)(TXPB)] (6) was prepared via the reaction of [NiBr2(dme)2] (dme = 1,2-dimethoxyethane) with TXPB. An X-ray crystal structure of light purple 6 revealed a square-planar geometry with a strong B–Br interaction {B–Br = 2.311(6) Å; ∑(C–B–C) = 344.5(7)°}. An 11B NMR chemical shift of 23 ppm was observed for 6, indicating that an appreciable B–Br interaction is maintained in solution. No signals were observed in the 31P{1H} NMR spectrum at room temperature, whereas a broadened 31P signal was observed at −20 °C, evolving into a sharp singlet at −67 °C. This behaviour suggests that at room temperature, square planar 6 exists in equilibrium with a paramagnetic tetrahedral isomer, present at a level below that detectable through Evans magnetic measurements.

The synthesis, and molecular and crystal structure of diphenyl(2-oxidonaphthylmethyl-iminoacetato)tin(IV)

1996 ◽  
Vol 74 (11) ◽  
pp. 2041-2047 ◽  
Author(s):  
Frank. E. Smith ◽  
Lian Ee Khoo ◽  
Ngoh Khang Goh ◽  
Rosemary C. Hynes ◽  
George Eng
Keyword(s):  
Crystal Structure ◽  
Elemental Analysis ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Trigonal Bipyramidal ◽  
Intermolecular Contacts ◽  
Distorted Trigonal Bipyramidal Coordination ◽  
Distorted Trigonal Bipyramidal

The new diorganotin complex ((C6H5)2Sn(OC10H6CH=NCH2COO)) was prepared and characterized by 1H NMR, IR, elemental analysis, and a single crystal X-ray diffraction study. The crystals are monoclinic, space group P21/a with a = 16.9167(9) Å, b = 19.1276(16) Å, c = 26.538(2) Å, β = 100.534(6)°, V = 8442.5(11) Å3, Z = 16, and Dcalc = 1.574 Mg m−3. The final discrepancy factors are RF = 0.030, and RW = 0.021 for 6524 significant reflections. The tin atom has a distorted trigonal bipyramidal coordination, with no short intermolecular contacts. The two axial Sn—O bonds of 2.12 Å and 2.09 Å and the equatorial Sn—N bond of 2.14 Å are among the shortest found in related complexes. Key words: diorganotin(IV), bicycloazastannoxide, trigonal bipyramidal, antitumour.

The preparation of bis(perfluoroethyl) tellurium difluoride and dichloride, trans perfluoroethyl tellurium monochloride tetrafluoride, trans bis(perfluoroethyl) tellurium tetrafluoride; and the preparation and X-ray crystal structure of perfluoroethyl tellurium trifluoride

1985 ◽  
Vol 63 (8) ◽  
pp. 2273-2280 ◽  
Author(s):  
Clement Lau ◽  
Jack Passmore ◽  
E. Keith Richardson ◽  
Tom K. Whidden ◽  
Peter S. White
Keyword(s):  
Vibrational Spectra ◽  
Electron Pair ◽  
Lone Pair ◽  
Axial Position ◽  
X Ray Diffraction ◽  
Tellurium Atom ◽  
Nmr Spectrum ◽  
X Ray ◽  
R Factor ◽  
Trigonal Bipyramidal

The reaction of (C2F5)2Te and XeF2 in a slurry of SO2ClF yielded (C2F5)2TeF2 essentially quantitatively. Chlorine and (C2F5)2Te gave (C2F5)2TeCl2. Both (C2F5)2TeF2 and (C2F5)2TeCl2 were assigned a trigonal bipyramidal geometry, on the basis of their 19F nmr and vibrational spectra, with the lone pair and C2F5 groups in equatorial, and the halogens in the axial positions. Perfluoroethyl tellurium trifluoride was prepared essentially quantitatively by the reaction of C2F5TeTeC2F5 and XeF2 in liquid SO2F2. The generally inert SO2ClF was found to react with C2F5TeTeC2F5 to give C2F5TeClxF3−x, and sulphur dioxide. The structure of C2F5TeF3 was determined by X-ray diffraction. The crystals are tetragonal with a = 10.129(4), c = 25.561(6) Å, and Z = 16. The structure was refined in space group I41/a to a conventional R factor of 0.051 for 901 observed reflections with I ≥ 3σ(I). Each tellurium atom is surrounded by two terminal fluorine atoms and two bridging fluorine atoms and a C2F5 group in an axial position around the apex of a distorted square pyramid. The square-pyramidal units are linked by symmetrical cis bridging atoms into endless chains with bridging angles of 180° and 177°. The geometry of the (C2F5TeF4) group is consistent with steric activity of the non-bonded electron pair. The 19F nmr and Raman spectra of C2F5TeF3 were recorded and the Raman spectrum assigned. Trans-C2F5TeClF4 was prepared by the reaction of C2F5TeTeC2F5, and an excess of ClF. The trans octahedral geometry of C2F5TeClF4 was unambiguously assigned from its 19F nmr and vibrational spectra. A mixture of trans-(C2F5)2TeF4 and trans-C2F5TeClF4 was obtained from the reaction of (C2F5)2Te and an excess of ClF. Trans geometry of (C2F5)2TeF4 was unambiguously assigned from its 19F nmr spectrum.

Darstellung, 11B-, 13C -, 1H-NMR- und Schwingungsspektren von 2,2' -Bipyridylundecahydro-closo-dodecaborat(1-) sowie Kristallstruktur von (Ph4As)[(2,2′-C10H8N2)B12Hn ]·CH3CN / Synthesis, 11B, 13C, 1H NMR and Vibrational Spectra of 2 ,2'-Bipyridyl-undecahydro-closo-dodecaborate(1-) and Crystal Structure of (Ph4As)[(2 ,2'-C10H8N2)B12H11]-CH3CN

1997 ◽  
Vol 52 (10) ◽  
pp. 1165-1168 ◽  
Author(s):  
T. Koch ◽  
W. Preetz
Keyword(s):  
1H Nmr ◽  
Deae Cellulose ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Monoclinic Space Group ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Ir And Raman

By reaction of (n-Bu4N)2[B12H12] with 2,2′-bipyridine at 190 °C the 2,2′-bipyridyl-undecahydro- closo-dodecaborate anion [(2,2′-C10H8N2)B12H11]− is formed which can be seperated from excess [B12H12]2− by ion exchange chromatography on diethylaminoethyl (DEAE) cellulose. The X-ray structure determination of (Ph4As)[(2, 2′-C10H8N2)B12H11] (monoclinic, space group P21/c with a = 13.3190(9), b = 10.1532(14), c = 28.788(3′) Å, β = 96.761(7)°, Z = 4) reveals that the bipyridyl substituent is bonded via one nitrogen atom. The 11B NMR spectrum exhibits a 1:5:5:1 pattern with ipso-B1 at -0.3, B2-B6 at -14.5, B7-B11 at -15.3 and antipodal-B12 at -15.9 ppm. The 13C and 1H NMR spectra show the characteristic patterns of the bipyridyl group in the range of 124.5 to 158.6 (13C) and 7.4 to 9.6 ppm (1H) respectively. The IR and Raman spectra exhibit characteristic BH stretching vibrations between 2445 and 2568 cm-1 and the stretching of the CC and CN bonds in the range of 1427 to 1619 cm-1 .

Synthesis, Spectroscopic Studies and Crystal Structure of 5,5’-Dimethoxy- 3,3’-methanediyl-bis-indole as the Inhibitor of Cell Proliferation of Human Tumors

2004 ◽  
Vol 59 (10) ◽  
pp. 1137-1142 ◽  
Author(s):  
Dorota Maciejewska ◽  
Maria Niemyjska ◽  
Irena Wolska ◽  
Marek Włostowski ◽  
Magdalena Rasztawicka
Keyword(s):  
Solid State ◽  
Solid State Nmr ◽  
Spectroscopic Studies ◽  
State Structure ◽  
X Ray Diffraction ◽  
Nmr Spectrum ◽  
X Ray ◽  
Nmr Methods ◽  
Cp Mas Nmr ◽  
Double Resonances

Abstract5,5’-Dimethoxy-3,3’-methanediyl-bis-indole (3) was synthesized in a reductive cyclisation process from (E)-5-methoxy-2-nitro-β -morpholinestyrene. The solid state structure was probed by single crystal X-ray diffraction and 13C CP/MAS NMR methods. The results of the X-ray analysis indicate insignificantly different structure of both methoxyindole fragments of the molecule, and this is the main reason for the appearance of the double resonances in the solid state NMR spectrum. Interesting N-H· · ·π interactions were observed which may have a functional role in biological features of 3. 5,5’- Dimethoxy-3,3’-methanediyl-bis-indole at conc. 1 · 10−4 M reduces the growth of MCF7 (breast), NCI-H460 (lung), and SF-268 (NCS) cells to 21, 0, and 48%, respectively.

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