Pentakis(Methoxycarbonyl)-Cyclopentadiene Chemistry .X. Crystal-Structure of the Charge-Transfer Complex Tropylium Pentakis(Methoxycarbonyl)Cyclopentadienide

1986 ◽  
Vol 39 (1) ◽  
pp. 165 ◽  
Author(s):  
MI Bruce ◽  
PA Humphrey ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Charge Transfer ◽  
Single Crystal ◽  
Structure Determination ◽  
Sandwich Structure ◽  
Charge Transfer Complex ◽  
Acetone Solution ◽  
Polar Solvents ◽  
X Ray

The compound [C7H7][C5(CO2Me)5] forms very long but thin orange-red needles, which, in contrast to a previous report, form orange-red to deep red solutions in polar solvents. Decolorization of an acetone solution occurs on standing, but the white compound so obtained has not been identified. Single-crystal X-ray structure determination at 295 K (R = 0.078 for 1030 'observed' reflections) shows the presence of an infinite sandwich structure comprising columns of interleaved anion and cation planes normal to b. Crystals are rthorhombic, Pbcn , a 18.206(6), b 13.954(12), c 17.243(5)Ǻ, Z 8.

scholarly journals Isolation and X-ray Crystal Structure of an Electrogenerated TEMPO–N3 Charge-Transfer Complex

2021 ◽  
Author(s):  
Hosea M. Nelson ◽  
Juno C. Siu ◽  
Ambarneil Saha ◽  
Duilio Cascio ◽  
Samantha N. MacMillan ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Charge Transfer ◽  
Charge Transfer Complex ◽  
X Ray

Calcium Carbodiimide Compounds Revisited – Syntheses, Single Crystal Structure Determination and Vibrational Spectra of Ca11N6[CN2]2, Ca4N2[CN2] and Ca[CN2]

2008 ◽  
Vol 63 (5) ◽  
pp. 530-536 ◽  
Author(s):  
Olaf Reckeweg ◽  
Francis J. DiSalvo
Keyword(s):  
Crystal Structure ◽  
Raman Spectrum ◽  
Single Crystal ◽  
Single Crystals ◽  
Vibrational Spectra ◽  
Structure Determination ◽  
X Ray ◽  
Characteristic Features ◽  
Reported Data ◽  
Correct Data

Single crystals of Ca11N6[CN2]2 (dark red needles, tetragonal, P42/mnm (no. 136), a = 1456.22(5), and c = 361.86(2) pm, Z = 2), Ca4N2[CN2] (transparent yellow needles, orthorhombic, Pnma (no. 62), a = 1146.51(11), b = 358.33(4), and c = 1385.77(13) pm, Z = 4) and Ca[CN2] (transparent, colorless, triangular plates, rhombohedral, R3̅m (no. 166), a = 369.00(3), and c = 1477.5(3) pm, Z = 3) were obtained by the reaction of Na2[CN2], CaCl2 and Ca3N2 (if demanded by stoichiometry) in arc-welded Ta ampoules at temperatures between 1200 - 1400 K. Their crystal structures were re-determined by means of single crystal X-ray structure analyses. Additionally, the Raman spectra were recorded on these same single crystals, whereas the IR spectra were obtained with the KBr pellet technique. The title compounds exhibit characteristic features for carbodiimide units with D∞h symmetry (d(C-N) = 121.7 - 123.8 pm and ∡ (N-C-N) = 180°). The vibrational frequencies of these units are in the expected range (Ca11N6[CN2]2: νs = 1230, νs = 2008; δ = 673/645/624 cm−1; Ca4N2[CN2]: νs = 1230, νs = 1986; δ = 672/647 cm−1; Ca[CN2]: νs = 1274, νs = 2031, δ = 668 cm−1). The structural results are more precise than the previously reported data, and with the newly attained Raman spectrum of Ca11N6[CN2]2 we correct data reported earlier.

scholarly journals Isolation and X-ray Crystal Structure of an Electrogenerated TEMPO–N3 Charge-Transfer Complex

2020 ◽  
Author(s):  
Hosea Nelson ◽  
Juno Siu ◽  
Ambarniel Saha ◽  
Duilio Cascio ◽  
Song-Bai Wu ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Charge Transfer ◽  
Theoretical Analysis ◽  
Charge Transfer Complex ◽  
Reactive Intermediates ◽  
Structural Elucidation ◽  
Catalytic Reactions ◽  
X Ray ◽  
Increasing Demand ◽  
Computational Predictions

Recent advances in radical-based catalytic reactions have created an increasing demand for the understanding of their mechanistic underpinnings. Structural elucidation of transient reactive intermediates via diffraction techniques, though rarely possible, is one of the most decisive ways to support such mechanistic hypotheses. Here we present the isolation, structural elucidation, and theoretical analysis of an electrochemically generated and catalytically relevant charge-transfer species formed between the azidyl radical and (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO). The unusual bent N–N–N angle and the pancake bonding between these two fragments highlight the weak bonding interactions present in this complex. This X-ray structure validates computational predictions as well as mechanistic proposals of TEMPO-mediated radical azidation reactions.

On the Origin of the Red Color of Aqueous-Solutions of 2,3-Dichloro-5,6-Dicyano-1,4-Benzoquinone (ddq). Crystal Structure of the Ammonium Salt of 2-Cyano-5,6-Dichloro-3-Hydroxy-1,4-Benzoquinone

1987 ◽  
Vol 40 (3) ◽  
pp. 625 ◽  
Author(s):  
HD Becker ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Aqueous Solutions ◽  
Single Crystal ◽  
Ammonium Salt ◽  
Structure Determination ◽  
Aqueous Ethanol ◽  
X Ray ◽  
Red Color ◽  
Hydrolysis Of

Hydrolysis of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in aqueous ethanol gives the deep-red coloured ammonium salt of a monocyano-dichloro-monohydroxy-benzoquinone which crystallizes in the tetragonal space group I41 /a, a 20.832(5), c 8.618(2) �, Z 16. Single-crystal X-ray structure determination (R 0.036 for 1185 'observed' reflections) show the presence of ammonium cations forming hydrogen bonds in the lattice alternatingly with the tautomeric anion of 2-cyano-5,6-dichloro-3-hydroxy-1,4-benzoquinone and 3-cyano-5,6-dichloro-4-hydroxy-1,2-benzoquinone.

Kristallzucht und Strukturaufklärung von K2[Pt(CN)4Cl2], K2[Pt(CN)4Br2], K2[Pt(CN)4I2] und K2[Pt(CN)4Cl2] · 2H2O/ Crystal Growth and Crystal Structure Determination of K2[Pt(CN)4Cl2], K2[Pt(CN)4Br2], K2[Pt(CN)4I2] and K2[Pt(CN)4]Cl2] · 2H2O

2004 ◽  
Vol 59 (5) ◽  
pp. 567-572 ◽  
Author(s):  
Claus Mühle ◽  
Andrey Karpov ◽  
Jürgen Nuss ◽  
Martin Jansen
Keyword(s):  
Crystal Structure ◽  
Infrared Spectroscopy ◽  
Crystal Growth ◽  
Single Crystal ◽  
Structure Determination ◽  
Spectroscopy Data ◽  
Crystal Data ◽  
X Ray ◽  
Raman And Infrared Spectroscopy

Abstract Crystals of K2Pt(CN)4Br2, K2Pt(CN)4I2 and K2Pt(CN)4Cl2 ·2H2O were grown, and their crystal structures have been determined from single crystal data. The structure of K2Pt(CN)4Cl2 has been determined and refined from X-ray powder data. All compounds crystallize monoclinicly (P21/c; Z = 2), and K2Pt(CN)4X2 with X = Cl, Br, I are isostructural. K2Pt(CN)4Cl2: a = 708.48(2); b = 903.28(3); c = 853.13(3) pm; β = 106.370(2)°; Rp = 0.064 (N(hkl) = 423). K2Pt(CN)4Br2: a = 716.0(1); b = 899.1(1); c = 867.9(1) pm; β = 106.85(1)°; R(F)N′ = 0.026 (N’(hkl) = 3757). K2Pt(CN)4I2: a = 724.8(1); b = 914.5(1); c = 892.1(1) pm; β = 107.56(1)°; R(F)N′ = 0.025 (N’(hkl) = 2197). K2Pt(CN)4Cl2 ·2H2O: a = 763.76(4); b = 1143.05(6); c = 789.06(4) pm; β = 105.18(1)°; R(F)N′ = 0.021 (N’(hkl) = 2281). Raman and infrared spectroscopy data are reported.

Crystal structure of (Z)-Cembr-4-ene-15,19,20-triol

1977 ◽  
Vol 30 (12) ◽  
pp. 2723 ◽  
Author(s):  
EN Maslen ◽  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Single Crystal ◽  
Least Squares ◽  
Structure Determination ◽  
Title Compound ◽  
X Ray Diffraction ◽  
Relative Configuration ◽  
Macrocyclic Ring ◽  
X Ray

The crystal structure of the title compound, CZOH3803 [compound (1) in ref.'], has been determined by single-crystal X-ray diffraction at 295(1) K and refined by least squares to a residual of 0.045 for 954 'observed' reflections. Crystals are monoclinic, P2', a 9.281(2), b 17.798(6), c 6.417(1) A, B 93.81(3)", Z 2. The structure determination establishes the relative configuration of the chiral centres within the 14-membered macrocyclic ring and shows the double bond to have the unusual (Z) configuration.

Crystal structure determination of Ag2Ga by single crystal X-ray diffraction

1998 ◽  
Vol 213 (12) ◽  
Author(s):  
A. E. Gunnæs ◽  
A. Olsen ◽  
P. T. Zagierski ◽  
B. Klewe ◽  
O. B. Karlsen ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structure Determination ◽  
Crystal Structure Determination ◽  
X Ray Diffraction ◽  
X Ray

AbstractThe crystal structure of

The Stereochemistry of Organometallic Compounds. LX. Rhodium-Catalyzed Reactions of Hydrogen and Carbon Monoxide With Alkenylanilines

1994 ◽  
Vol 47 (6) ◽  
pp. 1043 ◽  
Author(s):  
D Anastasiou ◽  
EM Campi ◽  
H Chaouk ◽  
GD Fallon ◽  
WR Jackson ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Carbon Monoxide ◽  
Single Crystal ◽  
Structure Determination ◽  
Cross Coupling ◽  
Organometallic Compounds ◽  
Single Crystal Structure ◽  
Crystal Structure Determination ◽  
X Ray ◽  
Catalyzed Reactions

Rhodium- catalysed reactions of o- or p- cyano-N-allylanilines with H2/CO give N- arylpyrrolidine aldehydes resulting from a double hydroformylation sequence. In contrast reactions of o- or p-methyl-N-allylanilines or N- allylaniline itself with H2/CO give ' dimeric ' compounds resulting from self-condensation reactions of an initially formed hydroformylation product together with varying amounts of the double hydroformylation product. Similar reactions of o-cyano-N-but-3-enylanilines give low yields of double hydroformylation products and major products arising from hydrogenation or cross coupling of intermediate enamines. The structure of one of these products, N-2-cyanophenyl-5-(N′-2-cyanophenyl-3-methyl-pyrrolidin-2-yl)-1,2,3,4-tetrahydropyridine (17) (IUPAC name: 2-[5-{1-(2-cyanophenyl)-3-methylpyrrolidin-2-yl}-1,2,3,4-tetrahydropyridin-1-yl] benzonitrile ) was confirmed by an X-ray single-crystal structure determination.

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