Synthesis of Rhodium Complexes with Novel Perfluoroalkyl Substituted Cyclopentadienyl Ligands

2001 ◽  
Vol 66 (2) ◽  
pp. 382-396 ◽  
Author(s):  
Jan Čermák ◽  
Kateřina Auerová ◽  
Huong Thi Thu Nguyen ◽  
Vratislav Blechta ◽  
Pavel Vojtíšek ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Chemical Shifts ◽  
Rhodium Complexes ◽  
Carbonyl Complexes ◽  
X Ray Diffraction ◽  
Metal Catalysis ◽  
Chloro Complexes ◽  
X Ray ◽  
Cyclopentadienyl Ligands ◽  
C Nmr

Mixtures of isomers of (perfluoroalkyl)tetramethylcyclopenta-1,3-dienes (CH3)4C5H(CF2)nCF3 (n = 3, 5, 7, 9) were synthesized as precursors of new cyclopentadienyl ligands for organotransition metal catalysis in fluorous biphase media and characterized by combination of GC-MS and 13C NMR spectroscopy. Rhodium(III) chloro complexes [Rh{(CH3)4C5(CF2)nCF3}Cl2]2 and rhodium(I) carbonyl complexes [Rh{(CH3)4C5(CF2)nCF3}(CO)2] were prepared from the cyclopentadienes and molecular structure of [Rh{(CH3)4C5(CF2)5CF3}Cl2]2 was determined by X-ray diffraction. The ligands are electronically close to the unsubstituted cyclopentadienyl as shown by values of carbonyl stretching frequencies in the carbonyl complexes. Neither carbonyl frequencies nor NMR chemical shifts of the complexes are substantially affected by the length of the perfluoroalkyl chain.

Hexacarbonyldieisen-stabilisierte Sulfimid-Derivate, Fe2(CO)6(μ-SNR) / Hexacarbonyl Diiron Stabilized Sulfimide Derivatives, Fe2(CO)6(μ-SNR)

1995 ◽  
Vol 50 (8) ◽  
pp. 1252-1256 ◽  
Author(s):  
Max Herberhold ◽  
Uwe Bertholdt ◽  
Wolfgang Milius
Keyword(s):  
Molecular Structure ◽  
X Ray Diffraction ◽  
Subsequent Reaction ◽  
X Ray ◽  
C Nmr

Hexacarbonyl diiron complexes of N-substituted sulfimides (SNR) have been obtained from the parent tetrahedrane, Fe2(CO)6(μ-SNH) (1), by deprotonation to give the anion Fe2(CO)6(μ-SN-) (2) and subsequent reaction with either trialkyloxonium or carbenium tetrafluoroborates. The new aza-diferra-thia-tetrahedranes, Fe2(CO)6(μ-SNR) (R = CH3 (3a), C2H5 (3b), CPh3 (3c), cyclo-C3Ph3 (3d), cyclo-C7H7 (3e), and cyclo-(C7H7)M (CO)3 with M = Cr (3f), Mo (3g), W (3h)) were characterized by their 1H and 13C NMR as well as their IR and MS spectra. The molecular structure of Fe2(CO)6[SN-cyclo-C7H7Mo(CO)3] (3g) has been determined by X-ray diffraction.

Structure cristalline et moléculaire d'un composé tricyclique contenant le cycle à dix chaînons dioxo diaza diphosphécine

1992 ◽  
Vol 70 (3) ◽  
pp. 809-816 ◽  
Author(s):  
Brigitte Duthu ◽  
Karim El Abed ◽  
Douraid Houalla ◽  
Robert Wolf ◽  
Joël Jaud
Keyword(s):  
Molecular Structure ◽  
Comparative Analysis ◽  
Double Bond ◽  
Mass Spectroscopy ◽  
Crystal And Molecular Structure ◽  
Accurate Information ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nmr Parameters ◽  
C Nmr

The sulfuration of the tricyclic organophosphorous dimer 2 leads easily to the dithiotricyclic derivative 3, which has been characterized by 31P, 1H, and 13C NMR, elemental analysis, and mass spectroscopy. Its crystal and molecular structure has been established by X-ray diffraction and compared to that of 2, which was previously determined. The comparative analysis of X-ray diffraction and NMR parameters gives accurate information about the molecular structure of both compounds. A numerical value of the anistropy cone of the P=S double bond is proposed. Keywords: phosphecine, NMR, X-ray, tricycle.

Crystal and molecular structure of Z- and E-1,2-dichloro-1,2-bis(2-chlorophenyl)ethylene. An X-ray and NMR study

1995 ◽  
Vol 73 (9) ◽  
pp. 1520-1525
Author(s):  
Luciano Antolini ◽  
Ugo Folli ◽  
Dario Iarossi ◽  
Adele Mucci ◽  
Silvia Sbardellati ◽  
...  
Keyword(s):  
Chemical Shifts ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Space Group ◽  
X Ray ◽  
Nmr Study ◽  
Phenyl Rings ◽  
A Cell ◽  
C Nmr

The crystal structures of the title compounds were determined by single crystal X-ray diffraction techniques. The molecule of the Z isomer, which crystallizes in the monoclinic space group C2/c with Z = 4 in a cell of dimensions a = 14.891 (2), b = 10.780(2), c = 8.769(1) Å, β = 97.47(2)°, V = 1395.7(7) Å3 has crystallographic twofold symmetry. The E form crystallizes in the orthorhombic space group Pbca with a = 11.730(1), b = 6.932(1), c = 16.841(1) Å, V = 1369.4(2) Å3 and Z = 4. Its molecules have crystallographically dictated [Formula: see text] symmetry. In both isomers the phenyl rings are roughly perpendicular to the average ethylene plane. The atoms characterizing this plane show significant deviations from planarity in the Z isomer. Marked bond-angle distortions at the ethene carbons of both structures are observed. The 1H and 13C NMR spectra of the compounds were measured and, particularly in the case of the 1H chemical shifts, fall into two quite separate spectral regions. At low temperature, two conformational isomers, those with different relative orientation of the C—Cl bonds of the phenyl rings, are observed in the spectrum of each compound. Keywords: chlorostilbenes, overcrowded molecules. X-ray structure, conformations, NMR spectroscopy.

The crystal and molecular structure of tetrabenzocyclodecan-1,6-dione

1980 ◽  
Vol 58 (8) ◽  
pp. 777-779 ◽  
Author(s):  
T. Stanley Cameron ◽  
Christine Chan ◽  
David G. Morris ◽  
Alistair G. Shepherd
Keyword(s):  
Molecular Structure ◽  
Diffraction Analysis ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Membered Ring ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Nmr Spectrum ◽  
X Ray ◽  
C Nmr

The crystals belong to the orthorhombic space group C222, with a = 9.226, b = 12.092, c = 16.513 Å, Z = 4. A single crystal X-ray diffraction analysis has shown that the title compound, in which all carbon atoms are sp2 hybridized, exists with the ten membered ring in a slightly twisted tub conformation. The 13C nmr spectrum is also reported.

On Attempts to Synthesize Lanthanide Complexes of the Dianionic Fluorenyl-alkoxo Ligand [C13H8-cyclo-C6H10-O]2-. Crystal Structure of (C13H9-cyclo-C6H10-O)LaI2(DME)2

2003 ◽  
Vol 58 (5) ◽  
pp. 389-394 ◽  
Author(s):  
Alexander A. Trifonov ◽  
Mikhail N. Bochkarev ◽  
Herbert Schumann ◽  
Sebastian Dechert
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Ir Spectra ◽  
Single Crystal ◽  
Lanthanide Complexes ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Elemental Analyses ◽  
C Nmr

Racemic trans-2-(9(H)-fluoren-9-yl)cyclohexanol, C13H9-cyclo-C6H10-OH (1), reacts with two equivalents of potassium naphthalenide in THF to give the dipotassium salt [C13H8-cyclo-C6H10-O]- K2(THF) (2). Recrystallization of 2 from pyridine affords the solvent free salt [C13H8-cyclo-C6H10- O]K2 (3). The reactions of LaI3(THF)4 with one equivalent of 2 or of YbI2(THF)2 with equimolar amounts of 2 produce the alkoxolanthanum diiodide (C13H9-cyclo-C6H10-O)LaI2(DME)2 (4) and the ytterbium dialkoxide (C13H9-cyclo-C6H10-O)2Yb(THF)0.5(5), respectively. [(Me3Si)2N]3Y reacts with three equivalents of 1 with elimination of hexamethyldisilazane and formation of the yttrium trialkoxide (C13H9-cyclo-C6H10-O)3Y (6). The compounds 2 to 5 were characterized by elemental analyses, 1H NMR, 13C NMR and IR spectra. The molecular structure of 4 was determined by single crystal X-ray diffraction.

[(Dimethylamino)methyl]ferrocene as an Amine Ligand: Study of the Bonding and X-Ray Crystal and Molecular Structure of the Pentacarbonyl{[(dimethylamino)methyl]ferrocene}tungsten Complex

2002 ◽  
Vol 67 (2) ◽  
pp. 228-234 ◽  
Author(s):  
Axel Fischer ◽  
Frank T. Edelmann ◽  
Klaus Jacob ◽  
Ivan Pavlík ◽  
Martin Pavlišta
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Crystal And Molecular Structure ◽  
X Ray Diffraction ◽  
Amine Nitrogen ◽  
X Ray ◽  
Nmr Data ◽  
Amine Ligand ◽  
C Nmr

The heterodinuclear complex [W(CO)5(Me2NCH2Fc)] (Fc = ferrocenyl) (1) resulting from the reaction of [(dimethylamino)methyl]ferrocene (2) and [W(CO)6] was studied by single-crystal X-ray diffraction. Its molecular structure confirms the coordination of the amine nitrogen in 2 to tungsten (d(W-N) = 2.359(5) Å) and reveals its trans-influence in the W(CO)5 moiety. The structure is discussed in relation to several previously referred spectroscopic (IR, UV-VIS, 13C NMR) data.

ss-NMR and single-crystal X-ray diffraction in the elucidation of a new polymorph of bischalcone (1E,4E)-1,5-bis(4-fluorophenyl)penta-1,4-dien-3-one

2019 ◽  
Vol 75 (6) ◽  
pp. 694-701
Author(s):  
Lívia O. A. Ferreira ◽  
Ana Karoline S. M. Valdo ◽  
José Antônio Nascimento Neto ◽  
Leandro Ribeiro ◽  
Jefferson R. D. da Silva ◽  
...  
Keyword(s):  
Chemical Shifts ◽  
Single Bond ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
Open Chain ◽  
Rotation Symmetry ◽  
X Ray ◽  
Cytotoxicity Assays ◽  
C Nmr

We report a new polymorph of (1E,4E)-1,5-bis(4-fluorophenyl)penta-1,4-dien-3-one, C17H12F2O. Contrary to the precedent literature polymorph with Z′ = 3, our polymorph has one half molecule in the asymmetric unit disordered over two 50% occupancy sites. Each site corresponds to one conformation around the single bond vicinal to the carbonyl group (so-called anti or syn). The other half of the bischalcone is generated by twofold rotation symmetry, giving rise to two half-occupied and overlapping molecules presenting both anti and syn conformations in their open chain. Such a disorder allows for distinct patterns of intermolecular C—H...O contacts involving the carbonyl and anti-oriented β-C—H groups, which is reflected in three 13C NMR chemical shifts for the carbonyl C atom. Here, we have also assessed the cytotoxicity of three symmetric bischalcones through their in vitro antitumour potential against three cancer cell lines. Cytotoxicity assays revealed that this biological property increases as halogen electronegativity increases.

scholarly journals Synthesis, X-Ray Characterization, IR Vibrational Frequencies, NMR Chemical Shifts and DFT Properties of 2,7-Dimethyl-2,7-Dicyanide-3,6-Diazaocta

2020 ◽  
Vol 9 (3) ◽  
pp. 396-404
Keyword(s):  
Molecular Structure ◽  
Organic Compounds ◽  
Electrostatic Potential ◽  
Molecular Electrostatic Potential ◽  
Chemical Shifts ◽  
Research Work ◽  
X Ray Diffraction ◽  
Energy Band Gap ◽  
X Ray ◽  
Potential Map

In our research work, we have synthesized 2,7-dimethyl-2,7-dicyanide-3,6-diazaoctane and confirmed its structure by using X-ray diffraction and spectrometric experiments. The experimentally obtained results were compared with theoretically results. The electronic properties of 2,7-dimethyl-2,7-dicyanide-3,6-diazaoctane have been analyzed by DFT. The energy band gap is computed at -1.800349 eV for the 2,7-dimethyl-2,7-dicyanide-3,6-diazaoctane shows that this molecular structure is lower kinetic stability and more reactivity. Molecular electrostatic potential map of electron density on an isosurface of electrostatic potential for the 2,7-dimethyl-2,7- dicyanide-3,6-diazaoctane indicates electron rich reactive sites were located over nitrogen (N≡C) atoms belong cyanide groups. Our research results will be important for syntheses new α-aminonitriles organic compounds and calculate theoretical properties of them.

scholarly journals Studies of Dihydropyridines by X-Ray Diffraction and Solid State 13C NMR

2007 ◽  
Vol 62 (4) ◽  
pp. 549-555 ◽  
Author(s):  
Martha S. Morales-Ríos ◽  
Antonio Martínez-Richa ◽  
Zurisaddai Hernández-Gallegos ◽  
Angelina Hernández-Barragán ◽  
Ricardo Vera-Graziano ◽  
...  
Keyword(s):  
Solid State ◽  
Phenyl Ring ◽  
Chemical Shifts ◽  
Carbonyl Groups ◽  
X Ray Diffraction ◽  
Substitution Pattern ◽  
Trans Orientation ◽  
X Ray ◽  
Nmr Data ◽  
C Nmr

Fourteen dimethyl 4-aryl-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylates (DHPs) were evaluated by means of single crystal X-ray diffraction in order to investigate the effects of the structure in the crystals on the solid state 13C NMR chemical shifts. These include the analysis of three DHPs containing two molecules per asymmetric unit. The chiral rotamer unit generated by the s-cis/s-trans orientation of the carbonyl groups, as well as by rotation of the 4-phenyl ring out of the bisecting plane containing the N1, C4, C7 atoms, resulted in a significant magnetic non-equivalence for the C2-CH3/C6-CH3 and the COOCH3 pairs of signals. The solid state 13C NMR data reveal that the substitution pattern of the phenyl ring has a marked effect on the extent to which the signals of the carbonyl carbon atoms and those of C-2/C-6 peaks are split.

Synthesis and Crystal Structure of 13-cis-Retinoate Aryl Derivatives

2011 ◽  
Vol 236-238 ◽  
pp. 3037-3040
Author(s):  
Wei Guo Yi ◽  
Dong Yan ◽  
Long Yong Xie ◽  
Jian Nan Xiang ◽  
Zhong Cao
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Retinoic Acid ◽  
Single Crystal ◽  
Diffraction Analysis ◽  
X Ray Diffraction ◽  
Monoclinic System ◽  
Synthesis And Crystal Structure ◽  
X Ray ◽  
C Nmr

A series of 13-cis-retinoate aryl derivatives were synthesized from 13-cis-retinoic acid and phenols or arylalcohol with dicyclohexylcarbodiimide (DCC) as reagent and 4-dimethylaminopyridine (DMAP) as catalyst. Their structures were characterized by1H,13C NMR, IR and MS. The crystal of 3a has been determined by single crystal X-ray diffraction analysis and its molecular structure has been confirmed. Compound 3a belongs to monoclinic system with space group P2 (1)/c, a = 22.235 (3) Å, b = 7.4117 (10) Å, c = 15.990 (2) Å, β = 109.253 (3) °, V = 2487.7 (6) Å3, Z = 4, R = 0.0613, ωR = 0.01437.

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