Crystal structures of 1,1-di(p-substituted phenyl)-2,2-dinitroethylenes

The X-ray crystal structures of 1,1-di(p-methylphenyl)-2,2-dinitroethylene (2), 1,1-di(p-methoxylphenyl)-2,2-dinitroethylene (3), 1,1-di(p-fluorophenyl)-2,2- dinitroethylene (4), 1,1-di(p-chlorophenyl)-2,2-dinitroethylene (5), and 1-phenyl-1- (p-nitrophenyl)-2,2-dinitroethylene (6) are reported and compared with that of 1,1-diphenyl-2,2-dinitroethylene (1). Owing to steric repulsion between the aryl rings, the single bond lengths between C(1) and the two ring carbons atoms are longer than the normal sp²–sp² bond distance of 1.46 Å. For 4–6 in which the aryl rings contain electron-withdrawing substituents (F, Cl, NO₂), the double bonds between C(1) and C(2) are shorter than those in 2 and 3, whose aryl rings containing electron-donating substituents. Furthermore, the steric repulsion between the aryl rings and C NO₂ fragments results in an appreciable twist about the central double bond. The two aryl rings of compounds 1–6 make dihedral angles of 77.7, 66.6, 62.8, 80.9, 82.0, and 71.2°, and the two C NO₂ fragments make dihedral angles of 68.5, 67.8, 65.9, 76.9, 73.0, and 71.9°, respectively.     

Spectroscopic Studies and Crystal Structure of 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl) methyl] Thiourea

Abstract  A new mannich base 1-[(2,5-dioxopyrrolidin-1-yl)(phenyl)methyl] thiourea formed by the direct condensation of thiourea, succinimide and benzaldehyde has been synthesized. The structure of this mannich base has been elucidated on the basis of micro elemental analysis, IR, ¹H NMR, ¹³C NMR, Mass and UV–Visible Techniques. The crystal structure of the title compound C₁₂ H₁₃ N₃ O₂ S was determined. It crystallizes in the monoclinic system, space group P2₁/c with a = 10.8234 (7) ?, b = 6.0355 (5) ?, c = 19.3692 (14) ?, β = 100.540(3)°, Z = 4 and V = 1243.94 (16) ?³. The structure was solved by the full-matrix least squares on F ² and had a refined R value of 0.0465 for 1,964 observed reflections. The crystal structure is stabilized by strong intramolecular C–H···O, C–H···S interactions and inter molecular N–H···O and S···S interactions. Graphical Abstract  This paper describes the spectroscopic and crystallographic studies of the title compound which is essential in ascertaining the structure of this new compound.      

Crystal and molecular structures of several tetrakis (nitrile)copper(I) complexes

The crystal structures of several [Cu(RCN)₄]X salts (R = Me, X = SO₃CF₃ ^–; R = Ph, X = BF₄ ^–, ClO₄ ^–, and PF₆ ^–) were determined using single crystal X-ray diffraction. All of the compounds contain distorted tetrahedral Cu(I) centers and noncoordinating anions, with the acetonitrile and benzonitrile structures containing three and one unique CuL₄ ⁺ complex in their respective asymmetric units. One important distortion is observed in the benzonitrile-Cu bonds, which are bent up to 23° away from linearity. The result is a flattened complex that maximizes the – tacking of the aromatic rings and is the dominant packing interactions between the complexes.     

Crystal structures of 3-[1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl]-1-[4-(methyl (I)/methoxy (II) phenyl)]-2-phenyl-propane-1-one

The compounds 3-(1-Benzenesulfonyl-3-phenylsulfanyl-1H-indol-2-yl)-1-[4-methyl (I)/methoxy (II)phenyl)]-2-phenyl-propane-1-one crystallize in triclinic space group P . The details are: compound I a = 11.941(6) ?, b = 12.154(7) ?, c = 13.006(7) ?, α = 63.124(8)°, β = 84.464(9)°, γ = 64.810(8)°, V = 1519.7(14) ?³, Z = 2, D _cal = 1.284 Mg m⁻³, and R = 0.0382 (wR = 0.0978); compound II a = 11.897(6) ?, b = 12.268(6) ?, c = 13.001(7) ?, α = 61.919(8)°, β = 83.480(8)°, γ = 64.676(7)°, V = 1504.0(14) ?³, Z = 2, D _cal = 1.333 Mg m⁻³, and R = 0.0422 (wR = 0.1049). The indole ring system in both the molecules I and II are not strictly planar and the dihedral angles formed by the pyrrole and benzo planes are 4.0(7)° and 3.5(8)°, respectively. The C–HO, C–Hπ and ππ types of interactions stabilize the molecules in the unit cell in addition to van der Waal's forces in I and II.     

Crystal and molecular structures of three modifications of the androgen dehydroepiandrosterone (DHEA)

The crystal and molecular structures of three forms of the androgen DHEA (dehydroepiandrosterone) have been determined by single crystal X-ray diffraction. They are: Form I, a polymorph crystallizing in space group P2₁ withZ=4; Form S1, a hydrate with composition DHEA. (1/4)H₂O, space group C2,Z=8; and Form S4, a methanol half-solvate, DHEA. (1/2)CH₃OH, space group C222₁,Z=8. The A, B, and C steroid ring conformations adopted in the five crystallographically independent DHEA molecules are invariably: chair, 8, 9-half-chair, and chair, respectively, while the D ring conformation ranges from a 14-envelope to a 13, 14-half-chair. In Forms I and S1, intermolecular hydrogen bonding is of the head-to-tail type with water molecules participating as donors in Form S1. In Form S4, DHEA molecules pack in head-to-head fashion, their hydroxyl groups being linked by hydrogen bonding to the solvent hydroxyl group. The hydroxyl H atoms of both DHEA and the included methanol are disordered, giving rise to an unusual linearly-propagating flip-flop hydrogen bonding scheme.     

Crystal and molecular structures of 11-hydroxy-7-oxodrim-8(9)-ene

The crystal structure of 11-hydroxy-7-oxodrim-8(9)-ene is determined. The crystals are monoclinic. The unit cell parameters are a = 16.716(4) Å, b = 11.052(3) Å, c = 7.542(3) Å, γ = 76.11°, Z = 4, μ = 1.476 cm⁻¹, ρ_calcd = 1.147 g/cm³, and space group P2₁. The structure is solved by the direct method and refined by the least-squares procedure to R = 0.045. There are two molecules of 11-hydroxy-7-oxodrim-8(9)-ene in the asymmetric unit. Both molecules have the same conformation of the skeleton and can be described as rotomers differing in orientation of the OH groups with respect to the skeleton. In both molecules, the cyclohexane rings have a usual chair conformation. In the crystal, two independent molecules are linked by a hydrogen bond. The molecular pairs related by the twofold screw axes are linked by hydrogen bonds into helices running along the z-axis of the crystal. The helices are bound through van der Waals interactions. __________ Translated from Kristallografiya, Vol. 45, No. 2, 2000, pp. 275–278. Original Russian Text Copyright ? 2000 by Chumakov, Simonov, Mazus, Popa, Vlad. Deceased.     

Crystal and molecular structures of two polymorphs of 4-methyl-2-nitroacetanilide (MNA)

Journal of Chemical Crystallography - The crystal and molecular structure of white (MNA-1) and yellow (MNA-3) forms of 4-methyl-2-nitroacetanilide have been determined by X-ray diffraction...     

Crystal and molecular structure of 7-[1-(2-carbomethoxyanilino)-1-(phenyl)-methyl]-quinolin-8-ol(CMAB-Oxine) and comparising consideration to CMAP-Oxine

C₂₄H₂₀N₂O₃, Pbc2₁, a = 11.338(4), b = 7.786(3), c = 44.381(6) Å, D_x = 1.29 Mg · m⁻³, V = 3.82053 · 10⁻²⁷ m³. There are eight molecules in the unit cell (two molecules, A and B, in the asymmetric unit). The substitution of N (CMAP-Oxine) by CH(CMAB-Oxine) in the aldehyde participant of reactants creates differences both in intermolecular contacts and orientation phenomenons of ring planes. A high degree of selectivity of the substitution position for both compounds is given. The reactions to the synthesis of both compounds are difficult to agree upon with the characteristic feature of the Mannichreaction and corresponded more to the character of the electrophilic substitution of aromatics.     

Crystal and molecular structures of 2-amino-5-(m-nitrophenyl)-1,3,4-Thiadiazole

2-Amino-5-(m-nitrophenyl)-1,3,4-thiadiazole (C₈H₆N₄O₂S) is studied using IR and ¹H NMR spectroscopy and X-ray diffraction (CAD4 automated diffractometer, λMoK _α, graphite monochromator, 957 unique reflections, Patterson method, R = 0.0326). The crystals are monoclinic, a = 11.832 Å, b = 9.862 Å, c = 8.353 Å, β = 110.40(3)°, V = 913.6(3) ų, d _calcd = 1.212 g cm^?3, μ(MoK _α) = 0.253 mm^?1, Z = 4, and space group P2₁/c. In the crystal, the C₈H₆N₄O₂S molecules form infinite layers parallel to the xz plane. Each layer contains aromatic rings with nitro groups that deviate from the layer plane on either side of the layer. In the packing, the aromatic rings with nitro groups of one layer fill spaces between aromatic rings with nitro groups of the adjacent layers.     

Crystal and molecular structures of benz-p-nitroanilide and benz-p-methoxyanilide

The crystal structures of the two carboxylic amides C₁₃H₁₀N₂O₃ (I) and C₁₄H₁₃NO₂ (II) have been determined by direct methods and refined by full-matrix least squares. The predominant structural feature is the hydrogen bonding (N-H?O=C) which influences the conformations of both structures.     

Crystal and molecular structure of 15-oxosparteine-N(1)-oxide perchlorate

[C₁₅H₂₅N₂O₂ ⁺·ClO ₄ ^– ,M _r =364.83, is monoclinic:P2₁,a=7.885(1),b=10.685(1),c=10.658(1) Å,=105.63(1)°,V _c =864.8(2) ų,Z=2,D _x =1.39(1)g cm^–3, (CuK)=1.54178 Å,(CuK)=21.4 cm^–1,F(000)=388 e,T=292K,R=0.066 for 1205 unique reflections. The piperidine ringsA, B, C, andD have chair, chair, boat, and half-chair conformations, respectively. The quinolizidine system (ringsA/B) has atrans configuration. The cations are interconnected by a hydrogen bond O(N1)O(C15) of 2.552(10) Å into chains along [010]. Atoms C(12) and C(13) from ringD of the cation are disordered. Very high thermal parameters of the oxygen atoms of the perchlorate anion may indicate its orientational disorder.     

Crystal and molecular structures of 1-phenyl-4,6-dimethylpyrimidine-2-thionetetraaquacobalt(II) dinitrate complex and of two pyrimidine thiones

The crystal structures of 1-phenyl-4,6-dimethylpyrimidine-2-thionetetraaquacobalt(II) dinitrate (I)a=9.032(2),b=12.458(2),c=18.067(3)Å,=103.25(3)°,Z=4;P2₁/c,R=0.049; 1-phenyl-4,6-dimethylpyrimidine-2-thione (II)a=12.005(3),b=10.090(2),c=9.649(2)Å,=104.4(1)°,Z=4;P2₁/n,R=0.038; and 4,6-dimethylpyrimidine-2-thione (III)a=15.485(3),b=13.255(3),c=7.127(2)Å,=104.3(1)°,Z=8,C2/c,R=0.041 are reported. In (I) the coordination around the cobalt(II) is distorted octahedral involving one ligand moleculevia sulphur and nitrogen atoms and four water molecules. It is relevant that the parameters in the complexed ligand are not different from those found in the uncomplexed one (II), excepting the distances on the nitrogen atom directly involved in the coordination. Bond distances and angles in compound (III) agree with those found in (II).     

Crystal and molecular structures of 2-(p-methylbenzyl)- and 2-(p-chlorobenzyl)-5-(p-bromobenzylidene)cyclopentanone. Influence of chloro and methyl substitution on solid-state reactivity

The crystal structures of the title compounds have been determined as part of an investigation into the factors which may influence the solid-state reactivity of benzylidene cyclopentanones. Thep-methyl derivative, which is photoactive in the crystalline state, in monoclinic:P2₁/c,a=18.381(2),b=11.209(2),c=8.285(2) Å,=94.46(12)°, andz=4. The chloro derivative, which is photostable, is also monoclinic:P2₁/c,a=17.522(4),b=7.906(2),c=11.888(2) Å,=91.19(14)°, andz=4. The structures were solved and developed via the heavy-atom method and refined by least-squares to finalR values of 0.062 and 0.061, respectively, using 1902 and 2356 observed reflections measured using an automatic diffractometer. The conformations of the two molecules in their crystal structures are significantly different and lead to dissimilar packing arrangements, which clearly account for the different photochemical behaviors.     

Crystal and molecular structure of trichloro(1-methylpent-4-enylammonium)platinum(II)

The crystal structure of the olefinic complex of platinum(II) with 1-methylpent-4-enylammonium has been determined from single crystal X-ray data and refined by least-squares methods toR=0.049. The monoclinic crystals have unit cell dimensionsa=11.500(4),b=6.088(4),c=18.961(5) Å,=116.92(4)°, space groupP2₁/c, andZ=4. In the zwitterionic complex the platinum atom is square-planar coordinated by the three chlorine atoms and by the double bond of the unsaturated ammonium cation.Deceased.     

Crystal and molecular structures of the orthorhombic and monoclinic isomers of catena-di-μ-chloro-semicarbazidecopper(II)

The crystal structures of two isomeric complex compounds of formula [Cu(Cl)₂(NH₂NHCONH₂)] have been determined by X-ray diffraction methods. The orthorhombic isomer has space groupPna2₁ and unit cell constants:a = 6·91(1),b = 8·30(1),c = 10·24(1) Å;Z = 4. The monoclinic isomer has space groupP2₁/c and unit cell constants:a = 6·91(1),b = 8·30(1),c = 11·32(1) Å, = 117·1(2)°;Z = 4. In both complexes coordination around copper is octahedral, with chains of coordination polyhedra along [100]. In the monoclinic compound, the two semicarbazide molecules, which are present in two adjacent octahedra along the chain, have the oxygen and nitrogen atoms in thetrans configuration, one with respect to the other, and are correlated by a centre of symmetry. In the orthorhombic compound, the two semicarbazide molecules are in thecis configuration and there is no centre of symmetry. In both compounds packing is determined by the NH···Cl and NH···O hydrogen bonds which join the chains together.The authors are indebted to Mr M. Lanfranchi who prepared the compounds and to Dr A. Immirzi who made abailable his computer programs.     

Crystal and molecular structure of 1-(2-aminoethyl)biguanide-isothiocyanato-copper(II) thiocyanate

The crystal structure of 1-(2-aminoethyl)biguanide-isothiocyanato-copper(II)thiocyanate, [Cu(aebg)(NCS)] (SCN) (aebg = NH₂. CH₂. CH₂. N=C(NH₂). NH. C(NH). NH₂) has been determined and refined by Fourier methods using three-dimensional X-ray data collected on a Weissenberg automatic diffractometer. The unit cell parameters are:a = 11·41(2),b = 8·81(2),c = 7·45(2) Å; = 87·6° (2); = 67·2° (2); = 70·1° (2);Z = 2.Assuming space group P¯1, the structure was refined down toR = 8·5 %. The coordination around Cu is slightly distorted square planar and concerns three N atoms from the aebg ligand (Cu-N = 1·988(8), 2·019(7), 1·963(5) Å) and the terminal N of an isothiocyanate group (Cu-N = 1·941(5) Å). Two unsymmetrical, long interactions (Cu-N = 3·367(7) and 2·947(7) Å), with the N atoms belonging to two NCS groupstrans with respect to the coordination plane, complete the coordination to a distorted octahedron. In the aebg ligand the double bonds are localized on the C-N groups, whose nitrogen atoms coordinate to the metal.This work was carried out with the aid of financial support from the Consiglio Nazionale delle Ricerche, Roma.     

Crystal and molecular structures of tri(o-tolyl)phosphinegold(I) purine-6-thiolate ethanol solvate (1/1) and tri(c-hexyl)phosphinegold(I) 6-methyl-2-thiouracilate

The crystal and molecular structures of the title compounds, [(o-tol)₃PAu(6-MP)]·EtOH and [(c-hexyl)₃PAu(6-Me-2-TU)], have been determined and each show the presence of a linear geometry about the Au atom; both of the thionucleobases function as thiolate ligands. Important interatomic parameters for [(o-tol)₃PAu(6-MP)] are Au–S 2.266(2), Au–P 2.239(2) and S–Au–P 177.03(8)° and for [(c-hexyl)₃PAu(6-Me-2-TU)]: Au–S 2.299(3), Au–P 2.244(3) and S–Au–P 176.1(1)°. Crystals of [(o-tol)₃PAu(6-MP)]·EtOH are monoclinic with space groupP2₁/n, and unit cell dimensionsa=10.067(2),b=10.518(2),c=25.416(4) , =98.42(2)°,Z=4. The structure was refined to finalR=0.040 for 4183 data withI3.0(I). Crystals of [(c-hexyl)₃PAu(6-Me-2-TU)] are monoclinic with space groupP2₁/c, and unit cell dimensionsa=9.692(4),b=15.822(4),c=15.775(3) , =94.00(2)°,Z=4,R=0.033 for 2666 data.     

Crystal and molecular structures of dimethyl 4-phenylthiosemicarbazidediacetate and its adduct with rhodium(II) acetate

The crystal structures of dimethyl 4-phenylthiosemicarbazidediacetate C₁₃H₁₇N₃O₄S (I) and its adduct [C₈H₁₂O₈Rh₂ (C₁₃H₁₇N₃O₄S)₂] (II) with rhodium(II) acetate are determined by X-ray diffraction analysis. The unit cell parameters of crystals I are as follows: a = 8.066(6) Å, b = 15.812(6) Å, c = 24.977(8) Å, β = 94.88(3)°, space group P2₁/n, and Z = 8. The unit cell parameters of crystals II are a = 8.513(1) Å, b = 16.055(1) Å, c = 16.071(3) Å, β = 104.99(1)°, space group P2₁/c, and Z = 2. In structure I, two crystallographically independent molecules considerably differ from each other in the mutual orientation of the structural fragments containing the ester groups. In the centrosymmetric dimeric complex II, the organic molecule I acts as a monodentate thio ligand and adopts only one conformation.     

Crystal and molecular structures of (1,3,4-thiadiazolyl-2)aminodipropionic and (5-methyl-1,3,4-thiadiazolyl-2)aminodipropionic acids

Crystal structures of (1,3,4-thiadiazolyl-2)aminodipropionic (I) and (5-methyl-1,3,4-thiadiazolyl-2) aminodipropionic (II) acids are determined [R = 0.0363 and 0.0529 for 2706 and 1614 reflections with I > 2σ(I) for I and II, respectively]. The similarity and distinctions in the hydrogen-bond systems and molecular-packing motifs of crystals I and II are discussed.     

Crystal and molecular structure of four compounds resulting from nucleophilic addition of 2H-pyrroles to dimethyl acetylene-dicarboxylate,methyl propiolate and phenyl isocyanate

Journal of Chemical Crystallography -