scholarly journals Syntheses, spectroscopy, and crystal structures of 3-(4-bromophenyl)-1,5-diphenylformazan and the 3-(4-bromophenyl)-1,5-diphenylverdazyl radical and the crystal structure of the by-product 5-anilino-3-(4-bromophenyl)-1-phenyl-1H-1,2,4-triazole

Author(s):  
Gregor Schnakenburg ◽  
Andreas Meyer

The title compounds, C19H15BrN4, C20H16BrN4and C20H15BrN4, are nitrogen-rich organic compounds that are related by their synthesis. The verdazyl radical, in which stacking leads to antiferromagnetic interactions, was reported previously [Iwaseet al.(2013).Phys. Rev. B,88, 184431]. For this compound, improved structural data and spectroscopic data are presented. The other two compounds have been crystallized for the first time and form stacks of dimers, roughly along thea-axis direction of the crystal. The formazan molecule shows signs of rapid intramolecular H-atom exchange typical for this class of compounds and spectroscopic data are provided in addition to the crystal structure. The triazole compound appears to be a side-product of the verdazyl synthesis.

2006 ◽  
Vol 61 (10-11) ◽  
pp. 588-594 ◽  
Author(s):  
Basavalinganadoddy Thimme Gowda ◽  
Jozef Kožíšek ◽  
Hartmut Fuess

TMPAThe effect of substitutions in the ring and in the side chain on the crystal structure of N- (2,4,6-trimethylphenyl)-methyl/chloro-acetamides of the configuration 2,4,6-(CH3)3C6H2NH-COCH3− yXy (X = CH3 or Cl and y = 0,1, 2) has been studied by determining the crystal structures of N-(2,4,6-trimethylphenyl)-acetamide, 2,4,6-(CH3)3C6H2NH-CO-CH3 (); N-(2,4,6- trimethylphenyl)-2-methylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2-CH3 (TMPMA); N-(2,4,6- trimethylphenyl)-2,2-dimethylacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH(CH3)2 (TMPDMA) and N-(2,4,6-trimethylphenyl)-2,2-dichloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CHCl2 (TMPDCA). The crystallographic system, space group, formula units and lattice constants in Å are: TMPA: monoclinic, Pn, Z = 2, a = 8.142(3), b = 8.469(3), c = 8.223(3), β = 113.61(2)◦; TMPMA: monoclinic, P21/n, Z = 8, a = 9.103(1), b = 15.812(2), c = 16.4787(19), α = 89.974(10)◦, β = 96.951(10)◦, γ =89.967(10)◦; TMPDMA: monoclinic, P21/c, Z = 4, a =4.757(1), b= 24.644(4), c =10.785(2), β = 99.647(17)◦; TMPDCA: triclinic, P¯1, Z = 2, a = 4.652(1), b = 11.006(1), c = 12.369(1), α = 82.521(7)◦, β = 83.09(1)◦, γ = 79.84(1)◦. The results are analyzed along with the structural data of N-phenylacetamide, C6H5NH-CO-CH3; N-(2,4,6-trimethylphenyl)-2-chloroacetamide, 2,4,6-(CH3)3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)-acetamide, 2,4,6-Cl3C6H2NH-COCH3; N-(2,4,6-trichlorophenyl)-2-chloroacetamide, 2,4,6-Cl3C6H2NH-CO-CH2Cl; N-(2,4,6-trichlorophenyl)- 2,2-dichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CHCl2 and N-(2,4,6-trichlorophenyl)- 2,2,2-trichloroacetamide, 2,4,6-Cl3C6H2NH-CO-CCl3. TMPA, TMPMA and TMPDCA have one molecule each in their asymmetric units, while TMPDMA has two molecules in its asymmetric unit. Changes in the mean ring distances are smaller on substitution as the effect has to be transmitted through the peptide linkage. The comparison of the other bond parameters reveal that there are significant changes in them on substitution.


2014 ◽  
Vol 70 (2) ◽  
pp. i9-i10 ◽  
Author(s):  
Amira Souilem ◽  
Mohamed Faouzi Zid ◽  
Ahmed Driss

The title compound, lithium/sodium iron(III) bis[orthomolybdate(VI)], was obtained by a solid-state reaction. The main structure units are an FeO6octahedron, a distorted MoO6octahedron and an MoO4tetrahedron sharing corners. The crystal structure is composed of infinite double MoFeO11chains along theb-axis direction linked by corner-sharing to MoO4tetrahedra so as to form Fe2Mo3O19ribbons. The cohesion between ribbonsviamixed Mo—O—Fe bridges leads to layers arranged parallel to thebcplane. Adjacent layers are linked by corners shared between MoO4tetrahedra of one layer and FeO6octahedra of the other layer. The Na+and Li+ions partially occupy the same general position, with a site-occupancy ratio of 0.631 (9):0.369 (1). A comparison is made withAFe(MoO4)2(A= Li, Na, K and Cs) structures.


2006 ◽  
Vol 71 (9) ◽  
pp. 1278-1302 ◽  
Author(s):  
Martin Valík ◽  
Pavel Matějka ◽  
Eberhardt Herdtweck ◽  
Vladimír Král ◽  
Bohumil Dolensky

A new bis-Tröger's base was prepared from a tetraamine precursor as a mixture of two diastereoisomers. One of the isomers has a chair-like geometry, and the other possesses a boat-like geometry, embodying molecular tweezers. A one-pot preparation of bis-TB isomers and their interconversion under acid conditions was also studied. Structures of both isomers were confirmed by single-crystal X-ray diffraction. Extensive spectroscopic data, including 1H and 13C NMR, IR and Raman spectra of the isomers, are given.


2010 ◽  
Vol 5 (4) ◽  
pp. 1934578X1000500 ◽  
Author(s):  
Mahmoud Mosaddegh ◽  
Maryam Hamzeloo Moghadam ◽  
Saeedeh Ghafari ◽  
Farzaneh Naghibi ◽  
Seyed Nasser Ostad ◽  
...  

Inula oculus-christi L. (Compositae) extract was chromatographed and three sesquiterpene lactones ergolide, gaillardin and pulchellin C were isolated. The structures of these compounds were determined by analysis of their spectroscopic data, and their crystal structures were defined using X-ray crystallography; the isolation of ergolide and pulchellin C is reported for the first time from this species. These three compounds were evaluated for their in vitro cytotoxic activity against MDBK, MCF7 and WEHI164 cells; ergolide and gaillardin exhibited lower and significantly different IC50 values compared with pulchellin C ( p<0.001).


1995 ◽  
Vol 48 (4) ◽  
pp. 741 ◽  
Author(s):  
GB Deacon ◽  
TC Feng ◽  
BW Skelton ◽  
AH White

The X-ray crystal structure of Nd (Odpp)3 ( Odpp- = 2,6-diphenylphenolate), obtained by sublimation of Nd ( Odpp )3( thf )2 ( thf = tetrahydrofuran ) [triclinic, Pī , a 15.835(5), b 13.499(10), c 10.955(11) Ǻ, α 116.25(7), β 92.87(7), γ 101.66(6)°, V 2031 Ǻ3, Z2, No 5726 'observed' data (I > 3σ(I)) refined to conventional R 0.047 shows a near triangular array of oxygens surrounding neodymium { Nd -O} 2.169 Ǻ, ∑ O- Nd -O 353.2° with additional, intramolecular Nd-η6-Ph chelate interactions { Nd -C} 3.046 Ǻ and Nd-η1-Ph ( Nd -C 2.964(7)Ǻ). There is a pseudotrigonal bipyramidal arrangement of the oxygens, the centroid of the η6-Ph, and the η1-carbon. The complex Nd ( Odpp )3( thf ), obtained by crystallization of Nd ( Odpp )3( thf )2 from toluene (monoclinic, P21/c, a 12.213(4), b 21.447(4), c 17.744Ǻ, β 104.25(2)°, V 4505 Ǻ3, Z 4, R 0.042 for No 8014) also has pseudotrigonal bipyramidal stereochemistry, with a triangular equatorial array of aryl oxide oxygens { Nd -O} 2.193 Ǻ; ∑ O- Nd -O 358.7°, an apical thf oxygen (Nd -O 2.446(3)Ǻ), and an apical intramolecular chelating phenyl group. As the last has three Nd -C contacts (3.094(5), 3.144(5), 3.010(5)Ǻ) significantly shorter than the other three (3.300(5), 3.427(5), 3.377(5)Ǻ), an η3-Ph-Nd interaction seems likely. For [ Nd ( Odpp )3( thf )2].2( thf ), obtained by crystallization from tetrahydrofuran without drying of the crystals, the X-ray structure (monoclinic, P21, a 10.230(2), b 21.919(5), c 13.411(4) Ǻ, β 101.15(2)°, V 2950 A3, Z2, R 0.058 for No 3237) reveals a distorted trigonal bipyramidal arrangement of three aryl oxide oxygens (two equatorial 2.208(9), 2.16(1) Ǻ; one axial 2.203(9) Ǻ) and two thf oxygens (one equatorial 2.44(1) Ǻ; one axial (significantly distant) 2.62(1) Ǻ). The X-ray structure of [La( Odpp )3( thf )2].2( thf ) shows it to be isostructural with the neodymium analogue.


1996 ◽  
Vol 52 (1) ◽  
pp. 151-158
Author(s):  
R. Jones ◽  
S. J. Rettig ◽  
J. R. Scheffer ◽  
J. Trotter ◽  
J. Yang

The effect of 1,5-disubstitution on the photochemistry of 9,10-ethenoanthracene-11,12-diesters has been studied and correlated with the crystal structures determined for several derivatives; photoproduct structures have been established from a crystal structure analysis of one of the products and from NMR correlations. The crystals studied are: (1)-Cl, dimethyl 1,5-dichloro-9,10-dihydro-9,10-ethenoanthracene-11,12-dicarboxylate, C20H14Cl2O4, P21/n; (1)-CN, 1,5-dicyano derivative, C22H14N2O4, P21/n; (1)-CN.0.5p-xylene, C22H14N2O4.0.5C8H10, P21/c; (1)-CN.xxylene, C22H14N2O4.xC8H10, P21/n; (1)-OMe, 1,5-dimethoxy derivative, C22H20O6, P{\bar 1}; (2b)-Cl, C20H14C12O4, dimethyl 1,5-dichloro-4b,8b,8c,8d-tetrahydrodibenzo[a, f]cyclopropa[c,d]pentalene-8c,8d-dicarboxylate, Pna21. The dibenzobarrelene molecules all have geometries and dimensions similar to those of related materials. In particular, the orientations of the two ester groups in each molecule differ, one being in general almost fully conjugated with the C(11)=C(12) double bond and the other almost non-conjugated. Relationships are sought between the ratios of the two regioisomeric photoproducts and molecular and crystal structures; both electronic and steric effects are considered, but no one effect seems to dominate.


2004 ◽  
Vol 68 (1) ◽  
pp. 167-175 ◽  
Author(s):  
G. D. Gatta ◽  
T. Boffa Ballaran

AbstractOrthorhombic edingtonite has been found coexisting with tetragonal edingtonite in a specimen from Ice River, British Columbia, Canada.We report data on the composition and crystal structure of the orthorhombic sample. Lattice parameters are: a = 9.5341(6), b = 9.6446(6), c = 6.5108(7)Å, V = 598.68(8)Å 3. The crystal structure was refined in space group P 21212 to R1 = 1.8% using 879 observed reflections. For the first time, evidence for splitting of the extra-framework Ba site in two different sites (Ba1, Ba2), ~0.37 Å apart, is demonstrated. A comparison with the published crystal structures of tetragonal and orthorhombic edingtonite is made.The present result supports the suggestion that the two edingtonite phases are a consequence of different nucleation phenomena and not different physicochemical conditions.


1994 ◽  
Vol 49 (7) ◽  
pp. 855-858 ◽  
Author(s):  
Michael Baier ◽  
Klaus Angermaier ◽  
Hubert Schmidbaur

Abstract Tris[(trimethylsilyl)oxy]antimony (Sb(OSiMe3)3, 1) has been prepared from SbCl3 and 3 equiv. of LiOSiMe3 in diethylether. According to mass spectrometric and NMR spectroscopic data, 1 appears to be a monomer in solution and in the gas phase. Dimerisation occurs, however, in the solid state as verified by an X-ray crystal structure determination. The unit cell contains three crystallographically independent monomers, two of which form one type of dimer, while the other is part of a centrosymmetrical dimer. In both types of dimers two Sb atoms are connected via two OSiMe3 groups to form distorted Sb2O2-squares. Together with the remaining 4 OSiMe3 groups and the two stereochemically active lone pairs, each Sb exhibits a trigonal bipyramidal coordination.


2010 ◽  
Vol 14 (06) ◽  
pp. 481-493 ◽  
Author(s):  
Bruno Bašić ◽  
John C. McMurtrie ◽  
Dennis P. Arnold

1,2-bis[10,15-di(3,5-di-tert-butyl)phenylporphyrinatonickel(II)-5-yl]diazene was synthesised via copper-catalyzed coupling of aminated nickel(II) 5,10-diarylporphyrin ("corner porphyrin") and its X-ray crystal structure was determined. Two different crystals yielded different structures, one with the free meso-positions in a trans-like orientation, and the other with a cis-like disposition. The free meso-positions of the obtained dimer have been further functionalized while the synthesis of a zinc analog has so far been unsuccessful. The X-ray crystal structure of the dinitro derivative of the dinickel(II) azoporphyrin was determined, and the structure showed a cis-like disposition of the nitro groups.


Sign in / Sign up

Export Citation Format

Share Document