A Speculative Discussion of the Structural Details of 1-Bromo-2-iodo-benzenes

2004 ◽  
Vol 59 (3) ◽  
pp. 264-268 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Oliver Minge ◽  
Stefan Nogai
Keyword(s):  
Single Crystal ◽  
Van Der Waals ◽  
Visible Region ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Structural Details ◽  
Steric Crowding ◽  
Speculative Discussion

The crystal and molecular structures of 2,4-dibromo-1-iodo-benzene (1) and 1,3-dibromo-2-iodobenzene (2) have been determined by single crystal X-ray diffraction. The proximity of two or three large halogen substituents (Br/I) induces only minor distortions of the C-C-Br/I angles (ca. 2°) and the halogen atoms remain in the plane of the molecules. These undistorted structures lead to short intramolecular, sub-van-der-Waals Br-I contacts [in the range 3.465(4) to 3.530(4) Å ]. The results suggest that the peripheral Br-I interactions have an attractive component which alleviates the repulsion out of steric crowding. The influence is associated with an absorption in the visible region and is possibly responsible for the enhanced reactivity of the 1,2-dihalobenzene molecules

Lewis-Base Adducts of Group 1B Metal(I) Compounds. XXI The Crystal and Molecular Structures of the Unsolvated Forms of Dibromotris(triphenylphosphine)dicopper(I) and 'step' Tetrabromotetrakis(triphenyl-phosphine)tetracopper(I)

1985 ◽  
Vol 38 (8) ◽  
pp. 1243 ◽  
Author(s):  
JC Dyason ◽  
LM Engelhardt ◽  
C Pakawatchai ◽  
PC Healy ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Molecular Structures ◽  
Lewis Base ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Triphenyl Phosphine ◽  
X Ray ◽  
Crystal And Molecular Structures

The crystal structures of the title compounds have been determined by single-crystal X-ray diffraction methods at 295 K. Crystal data for (PPh3)2CuBr2Cu(PPh3) (1) show that the crystals are iso-morphous with the previously studied chloro analogue, being monoclinic, P21/c, a 19.390(8), b 9.912(5), c 26.979(9) Ǻ, β 112,33(3)°; R 0.043 for No 3444. Cu( trigonal )- P;Br respectively are 2.191(3); 2.409(2), 2.364(2) Ǻ. Cu(tetrahedral)- P;Br respectively are 2.241(3), 2.249(3); 2.550(2), 2.571(2) Ǻ. Crystals of 'step' [PPh3CuBr]4 (2) are isomorphous with the solvated bromo and unsolvated iodo analogues, being monoclinic, C2/c, a 25.687(10), b 16.084(7), c 17.815(9) Ǻ, β 110.92(3)°; R 0.072 for No 3055. Cu( trigonal )- P;Br respectively are 2.206(5); 2.371(3), 2.427(2) Ǻ. Cu(tetrahedral)- P;Br are 2.207(4); 2.446(2), 2.676(3), 2.515(3) Ǻ.

Reactions between ruthenium chlorides and trimethyl phosphite : crystal and molecular structures of RuCI3(NH3)[P(OMe)3]2

1980 ◽  
Vol 33 (1) ◽  
pp. 195 ◽  
Author(s):  
MI Bruce ◽  
DA Kelly ◽  
GM Mclaughlin ◽  
GB Robertson ◽  
IB Tomkins ◽  
...  
Keyword(s):  
Single Crystal ◽  
Diffraction Study ◽  
Molecular Structures ◽  
Trimethyl Phosphite ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
A Minor

The reaction between RuCl3,nH2O and P(OMe)3 affords RuCl2[P(OMe)3]4; one batch of RuCl3,-nH2O also gave amminetrichlorobis(trimethyl phosphite)ruthenium(III), RuCl3(NH3)[P(OMe)3]2, as a minor product. The structure of this complex has been determined from a single-crystal X-ray diffraction study (4598 data, R 0.065, Rw 0.090): the ruthenium is approximately octahedrally coordinated by the three mer chloro, two trans P(OMe)3 and one NH3 ligands. Crystals are monoclinic,P21/n, a 8.725(3), b 18.286(7), c 10.936(4)Ǻ, β 94.57(3)°, Z 4.

Structural and spectroscopic characterization of isotypic sodium, rubidium and cesium acesulfamates

2015 ◽  
Vol 70 (7) ◽  
pp. 491-496 ◽  
Author(s):  
Oscar E. Piro ◽  
Gustavo A. Echeverría ◽  
Eduardo E. Castellano ◽  
Beatriz S. Parajón-Costa ◽  
Enrique J. Baran
Keyword(s):  
Aqueous Solutions ◽  
Single Crystal ◽  
Potassium Salt ◽  
Spectroscopic Characterization ◽  
Molecular Structures ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures

AbstractThree new acesulfamate salts, NaC4H4NO4S, RbC4H4NO4S and CsC4H4NO4S, were prepared by reactions in aqueous solutions and thoroughly characterized. Their crystal and molecular structures were determined by single crystal X-ray diffraction methods. They crystallize in the monoclinic space group P21/a with a = 7.2518(2), b = 8.9414(4), c = 10.5929(4) Å, β = 99.951(3)°, V = 676.52(4) Å3 for the Na salt; a = 7.4663(3), b = 9.6962(4), c = 10.4391(4) Å, β = 95.150(3)°, V = 752.68(5) Å3 for the Rb salt and a = 7.5995(4), b = 9.9439(4), c = 10.8814(6) Å, β = 91.298(5)°, V = 822.08(7) Å3 for the Cs salt, and Z = 4 molecules per unit cell. The three compounds are isotypic to each other and to the previously reported potassium salt. The metal ions are in irregular polyhedral coordination with six neighboring acesulfamate anions through their nitrogen and carbonyl and sulfoxide oxygen atoms. The FTIR spectra of the compounds were also recorded and are briefly discussed.

Crystal and molecular structures of two aryldiazenato complexes of molybdenum of the type [Mo(N2Ar)(S2CNMe2)3]

1980 ◽  
Vol 33 (4) ◽  
pp. 717 ◽  
Author(s):  
GA Williams ◽  
ARP Smith
Keyword(s):  
Nitrogen Atom ◽  
Single Crystal ◽  
Crystal Lattice ◽  
Magnetic Moments ◽  
Nitro Derivative ◽  
Molecular Structures ◽  
Electron Donors ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures

The crystal and molecular structures of the aryldiazenato complexes of molybdenum, [Mo(N2C6H5)(S2CNMe2)3],CH2Cl2 (1), and the m-nitro derivative [Mo{N2C6H4(m-NO2)}-(S2CNMe2)3]2,�CH2Cl2,�H2O (2), have been determined by single-crystal X-ray diffraction methods at 294 K. Crystals of (1) are monoclinic, P21/n, a 13.056(1), b 13.366(1), c 15.350(1) Ǻ, β 93.80(1)°, Z 4. Crystals of (2) are monoclinic, C2/c, a 32.442(8), b 17.670(4), c 17.867(3) Ǻ, β 99.03(1)°, Z 8. Automatic diffractometry has provided significant Bragg intensities for 2849 (1) and 3898 (2) independent reflections and the structures have been refined by least-squares methods to R 0.036 (1) and 0.053 (2). The two unique molybdenum complexes in (2) are essentially chemically equivalent. The complexes in (1) and (2) possess the expected seven-coordinate pentagonal bipyramidal structures with the aryldiazenato ligands, singly bent, occupying axial positions. The N=N-Mo units are linear, and the bonding can be represented by N=N→Mo with the aryldiazenato ligands three-electron donors. The m-nitro substituent in (2) interacts with a dithiocarbamate (dtc) nitrogen atom, thereby affecting the redox behaviour of this compound. The possible significance of this O(nitro)...N(dtc) interaction to the mechanism, whereby included nitrobenzene solvent in the crystal lattice lowers the magnetic moments of ferric dithiocarbamates, is discussed.

Azaborolinyl-Komplexe, IX Die Kristall- und Molekülstrukturen von zwei Isomeren des Bis(1-tert-butyl-2-methyl-η-1.2-azaborolinyl)cobalts/Azaborolinyl Complexes, IX The Crystal and Molecular Structures of Two Isomers of Bis(1-tert-butyl-2-methyl-η-1,2-azaborolinyl)cobalt

1983 ◽  
Vol 38 (4) ◽  
pp. 485-492 ◽  
Author(s):  
Günter Schmid ◽  
Roland Boese
Keyword(s):  
Single Crystal ◽  
Cobalt Atom ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Sandwich Complexes ◽  
X Ray ◽  
Ring Carbon ◽  
Tert Butyl ◽  
Crystal And Molecular Structures ◽  
Packing Effect

Abstract The crystal and molecular structures of two isomers of bis(1-tert-butyl-2-methyl-η-1,2-azaborolinyl)cobalt have been determined by single-crystal X-ray diffraction methods. Isomer 1 shows a clockwise, isomer 2 an anti-clockwise conformation of the azaborolinyl rings. In both compounds the azaborolinyl rings have staggered orientations with opposite positions of the tert-butyl groups. The rings in 1 and 2 are slipped so that the three ring carbon atoms are closer to the cobalt atom than the BN groups. The staggered orientation of the ligands in 2 is probably due to a packing effect, as in similar sandwich complexes the anti-clockwise conformers show eclipsed orientation.

Thermolytic conversion of an acetamido-substituted cyclopropane into a cyclopentenone. Crystal and molecular structures of 2-Spiro-substituted Benzofuran-3-ones

1984 ◽  
Vol 37 (11) ◽  
pp. 2225
Author(s):  
H Becker ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Molecular Structures ◽  
Starting Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Ring Enlargement

The thermolysis of an N-methylacetamido cyclopropane, spiro-substituted by a benzofuran-3-one moiety, was found to result in the elimination of methylamine and the formation of the correspondingly spiro-substituted cyclopentenone. The structures of starting material and product were determined by single-crystal X-ray diffraction methods and a mechanism for the elimination/ring enlargement reaction is proposed on the basis of the X-ray results.

The stereochemistry of Bis(α,α'-diimine)copper(I) complexes: the crystal and molecular structures of Bis(2,9-dimethyl-1,10-phenanthroline)copper(I) bromide hydrate, Bis(4,4',6,6'-tetramethyl-2,2'-bipyridine)copper(I) chloride dihydrate, and Bis(2,9-dimethyl-1,10-phenanthroline)copper(I) nitrate dihydrate (a redetermination)

1984 ◽  
Vol 37 (3) ◽  
pp. 649 ◽  
Author(s):  
JF Dobson ◽  
BE Green ◽  
PC Healy ◽  
CHL Kennard ◽  
C Pakawatchai ◽  
...  
Keyword(s):  
Single Crystal ◽  
Molecular Structures ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Tetrahedral Geometry ◽  
X Ray ◽  
Chloride Dihydrate ◽  
Crystal And Molecular Structures ◽  
Considerable Distortion ◽  
Axial System

The crystal structures of the title compounds have been determined by single-crystal X-ray diffraction methods at 295 K, and refined by least-squares methods. Crystal data for [Cu(Cl4H12N2)2] Br.H2O (1) are: monoclinic, P21/c, a 14.067(4), b 17.687(6), c 10.337(5) �, β 91.04(3)�, with R 0.038, R' 0.040 for 1855 'observed' reflections. Crystal data for [Cu(Cu14H12N2)2] C1.2H2O (2) are: triclinic, P1, a 15.305(2), b 13.164(2), c 7.344(3) �, α 83.03(3), β 93.83(3), γ 108. 11260(3)�, with R 0.051, R' 0.053 for 1293 'observed' reflections. Crystal data for [Cu(Cl4H12N2)2] Br.H2O (3) are: triclinic, P1, a 7.619(2), b 11.967(3), c 15.534(3) �, α 71.26(1), β 82.13(1), γ 86.86(2)�, with R 0.043, R' 0.052 for 2335 'observed' reflections. The anionic and solvent species are uncoordinated in all three compounds. Cu-N bond lengths range from 2.027(5) to 2.053(5) �. The copper(1) environment (CuN4) in each complex shows considerable distortion from tetrahedral geometry. N-Cu-N intraligand angles range from 81.0(2) to 83.0(2)�, while N-Cu-N interligand angles range from 114.7(2) to 135.2(2)�. The variation in interligand angles can be described in terms of three independent rotations of ligand 2 about an orthogonal axial system defined by ligand 1.

Kristall- und Molekülstruktur von As2P2S7/ Crystal and Molecular Structure of As2P2S7

1984 ◽  
Vol 39 (8) ◽  
pp. 1088-1091 ◽  
Author(s):  
Wolfgang Hönle ◽  
Claus Wibbelmann ◽  
Wolfgang Brockner
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Bond Length ◽  
Crystal And Molecular Structure ◽  
Molecular Structures ◽  
X Ray Diffraction ◽  
Group V ◽  
X Ray ◽  
Bond Lengths ◽  
Crystal And Molecular Structures

AbstractThe crystal and molecular structures of As2P2S7 has been determined by single crystal X-ray diffraction (space group V 21/c; Z = 4; a = 1174.6(16) pm; b = 823.9(7) pm; c = 1140.1(10) pm; β - 94.43(9)°; R = 0.073. The molecule is isosteric to P4S7 and possesses C2v symmetry. Mean bond lengths are: d (As-As) = 250.9 pm; d (As-S ) = 225.7 pm; d(P - S) = 208.3 pm and d(P = S) = 193.2 pm. The observed As -As bond length agrees well with spectroscopic results

Single-crystal X-ray structure determinations of vardenafil, vardenafil dihydrate, vardenafil monohydrochloride trihydrate and vardenafil dihydrochloride hexahydrate

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Dedong Wu ◽  
Faraj Atassi
Keyword(s):  
Crystal Structure ◽  
Synchrotron Radiation ◽  
Single Crystal ◽  
Molecular Structures ◽  
Free Base ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
Structure Determinations ◽  
Good Agreement

AbstractThe crystal and molecular structures of vardenafil (free, unprotonated base), vardenafil dihydrate and the hydrochloride salts, vardenafil monohydrochloride trihydrate and vardenafil dihydrochloride hexahydrate, were determined by single-crystal X-ray diffraction. The crystal structure of vardenafil monohydrochloride trihydrate is in good agreement with the published crystal structure obtained by powder diffraction using synchrotron radiation. This work shows that the crystal structure of anhydrous vardenafil free base is very similar to the crystal structure of sildenafil free base.

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