Spectral,BVS, and Thermal Studies on Bisdithiocarbamates of Divalent Zn,Cd, and Their Adducts: Single Crystal X-Ray Structure Redetermination of (Diiodo) (Tetraethylthiuramdisulfide)mercury(II), [Hg(tetds)I2]

The current article describes the TG and DT analyses of divalent Zn, Cd, and Hg dithiocarbamato (dtc) complexes and their adducts (dchdtc = N,N-dicyclohexyldithiocarbamate anion, 4-mpzdtc = 4-methylpiperazinecarbodithioato anion, padtc = N,N′-(iminodiethylene)bisphthalimidedithiocarbamate anion, pipdtc = piperidinecarbodithioate anion, 1,10-phen = 1,10-phenanthroline, and 2,2′-bipy = 2,2′-bipyridine) along with the structural reinvestigation of [Hg(tetds)I ₂ ], where tetds = tetraethylthiuramdisulfide. In the case of Zn(II) and Cd(II) dithiocarbamates and their nitrogenous adducts, thermal decomposition of the nitrogenous bases is followed by the decay of dithiocarbamate leading to the formation of ZnS or CdS as residue. The interaction of iodine with [Hg(dedtc) ₂ ] in CHCl ₃ results in the oxidation of diethyldithiocarbamate leading to the formation of [Hg(tetds)I ₂ ], and the structure was redetermined because the earlier determination was by a Polaroid crystallographic technique with a higher R value. The S-Hg-I bond angles [105.09(3); 105.59(3); 109.26(3), and 100.99(3)°] indicate the near tetrahedral environment around the metal ion. ¹ H and ¹³ C NMR spectra of the complex were analyzed. Whether the product formed upon oxidation is a disulfide or an iodo-substituted product, in the present investigation, is clearly decided by the bulkiness of the substituent attached to the nitrogen. Interestingly, the steric influence is a deciding factor only in the case of mercury compounds and the dithiocarbamates involving Zn, Cd forms of the disulfide complexes.     

Supramolecular Organization in Tetra Aqua (μ-8-Hydroxyquinoline-5-sulfonate) Barium (II) and Ag···I Interactions in a Pseudopolymorphic Form of (7-Iodo-8-hydroxyquinoline-5-sulfonate) Silver (I) Monohydrate

Abstract  

The complexes, Ba (HQS) (H₂O)₄ (HQS = 8-hydroxyquinoline-5-sulfonic acid) (1) and Ag (HIQS) (H₂O) (Ferron = 7-iodo-8-hydroxyquinoline-5-sulfonic acid) (2) have been synthesized and characterized by X-ray diffraction analysis and spectroscopic studies. In compound 1, Ba²⁺ ion has a nine-coordinate monocapped antiprismatic geometry. In compound 2, Ag⁺ has distorted tetrahedral coordination and Ag···I interactions generate the supramolecular architectures. The complexes have been characterized by FT-IR and UV–Visible measurements. In both the structures, the inversion-related organic ligands are stacked over one another leading to three-dimensional networks.     

Pseudokobusine

The title compound, hetisan-6,11β,15β-triol, C₂₀H₂₇NO₃, is a hetisane-type diterpenoid alkaloid. It consists of six six-membered rings and two five-membered rings. The fused-ring system contains three chair, two boat, one distorted boat and two envelope conformations. Intramolecular and intermolecular hydrogen bonds are present between the O atoms, with O⃛O separations of 3.006 (3) and 2.743 (3) Å, as well as an O⃛N intermolecular interaction of 2.887 (3) Å.     

Crystal and Molecular Structure of 1-( p -Tolyl)-4-[4-(N-naphthalimido)butyl]piperazine

An X-ray structure analysis of 1-(p-tolyl)-4-[4-(N-naphthalimido)butyl]piperazine (I) was carried out: a=9.551(3), b=13.775(3), á=8.917(4) , =103.96(3), =101.47(4), =92.60(3)°, V=1110.4(7) ³, Z=2,_calc=1.279 g/cm³, =0.644 mm, space group P 1, 4239 nonzero reflections, R=0.056. The molecule is linear elongated. The p-tolyl and naphthalimide fragments are almost planar, while the piperazine cycle has a chair conformation. The long well-packed molecules form parallel and antiparallel chains with van der Waals interactions between them.     

2,2′-Diphenyl-Δ3,3′-bi-3H-indole-1,1′-dioxide: Molecular interactions and crystal structure

The Dinitrone 2,2-diphenyl-^3,3-bi-3H-indole-1,1-dioxide acts as a demethylating and dehydrogenating agent. The mechanism of interaction of the dinitrone with donors and acceptors does not involve intermediate charge-transfer complexes probably due to a self association between dinitrone molecules (as supported by X-ray determinations). The crystal structure of the dinitrone was obtained by direct methods;a=9.967 (2),b=19.817 (3),c=10.875 (2) Å, =111.2 (2)°, space group P2₁/n. The finalR andR _w were 0.089 and 0.063 for all measured reflexes.

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2,2-Diphenyl-^3,3-bi-3H-indol-1,1-dioxid: Molekulare Wechselwirkungen und Kristallstruktur

Zusammenfassung Das Dinitron 2,2-Diphenyl-^3,3-bi-3H-indol-1,1-dioxid wirkt als Demethylierungs- und Oxydationsmittel. Die Wechselwirkung des Dinitrons mit Elektronen-Acceptoren und Elektronen-Donatoren geht wegen der Selbstassoziation zwischen den Dinitron-Molekülen ohne die dazwischenliegende Bildung eines Charge-Transfer-Komplexes vor sich; das wird auch von Röntgenstrukturuntersuchungen gestützt. Die Kristallstruktur wurde mit direkten Methoden ermittelt:a=9.967 (2),b=19.817 (3),c=10.875 (2) Å; =111.2 (2)°. P2₁/n. Die endgültigen WerteR undR _w waren 0.089 und 0.063 für alle gemessenen Reflexe.

     

Crystal structures of condensation products of 3,5-dibromosalicylic aldehyde with streptocide, norsulfazole, and ethazole

Crystal structures of 4-[(3,5-dibromo-2-hydroxy-benzylidene)-amino]-benzenesulfonamide (I), 4-[(3,5-dibromo-2-hydroxy-benzylidene)-amino]-N-thiazol-2-yl-benzenesulfonamide (II), and 4-[((3,5-dibromo-2-hydroxy-benzylidene)-amino]-N-(5-ethyl-1,3,4-thiadiazol-2-yl)-benzenesulfonamide (III) have been determined. The crystals of I are monoclinic, a = 8.645(2) Å, b = 12.622(3) Å, c = 14.414(3) Å; β = 104.31(3)°, space group P2₁/n, Z = 4, R = 0.0642. The crystals of II are also monoclinic, a = 10.313(2) Å, b = 11.288(2) Å, c = 15.766(3) Å; α = 99.37(3)°, space group P2₁/c, Z = 4, R = 0.0635. The crystals of III are triclinic, a = 10.567(2) Å, b = 10.849(2) Å, c = 18.432(4) Å; α = 75.97(3)°, β = 89.71(3)°, γ = 87.33(3)°, space group P-1, Z = 4, R = 0.0644. The asymmetric part of the unit cell of compounds I and II contains a single molecule of the Schiff’s base, while in III two independent azomethine molecules A and B. The studied compounds I–III adopt the E-configuration relatively to the double azomethine bond C=N. Owing to phenolic oxygen together with nitrogen and oxygen atoms of the sulfonamide group, compound I makes in a crystalline state a two-dimensional hydrogen bonded network parallel to the plane (1 0 1). Compound II forms centrosymmetric dimers in the crystals via N-H…N hydrogen bonds. These dimers, in their turn, are connected by hydrogen bonds O-H…O into infinite chains running along the double screw axis b. As in II, molecules and of compound III form centrosymmetric dimers through hydrogen bonding N-H…N. These dimers are linked into infinite chains running along the c axis by hydrogen bonds C-H…O. The π-π-stacking interaction of aromatic rings is observed in all the compounds studied.     

Synthesis,Spectral, Valence‐Bond Parameters,and Single Crystal X‐ray Structural Studies on [Ni(dnpdtc)(PPh3)(NCS)] and [Ni(dnpdtc)(PPh3)(CN)]

Two new nickel complexes withplanar surrounding of Ni [Ni(dnpdtc)(PPh₃)(NCS)] (1) and [Ni(dnpdtc)(PPh₃)(CN)] (2) (dnpdtc=N, N‐dipropyldithiocarbamate) were prepared from the parent dithiocarbamate and were characterized by elemental analysis, electronic, IR and NMR spectra. The structures of both the complexes were determined by single crystal X‐ray crystallography. Thioureide stretching vibrations occur at 1528 cm^‐1 and 1521 cm^‐1 for 1 and 2 respectively. Large ³¹P chemical shifts were observed for the two compounds. A significant asymmetry in Ni—S bond distances was observed in compound 1 [2.1700(16) and 2.2251(17)Å] whereas in compound 2 the bond distances were almost similar [2.2100(14) and 2.2122(13)Å]. A marginal difference was observed with respect to the thioureide bond distances [1.340(6)Å for 1 and 1.312(5)Å for 2 ]. The observation clearly supports the less effective trans influence of SCN^— over PPh₃. However, PPh₃ and CN^— show almost similar trans influence.     

Hydrogen-bonded supramolecular motifs in crystal structures of trimethoprim barbiturate monohydrate (I) and 2-amino-4,6-dimethylpyrimidinium barbiturate trihydrate (II)

In the present study, we report the crystal structures of two organic salts, namely 2,4-diamino-5-(3′,4′,5′-trimethoxybenzyl)pyrimidinium (TMP) barbiturate monohydrate (TMPBAR) (I), 2-amino-4,6-dimethylpyrimidinium (AMPY) barbiturate trihydrate (AMPYBAR) (II). In both complexes, one ring nitrogen of TMP and AMPY are protonated as a result of proton transfer from the−CH₂ group of barbituric acid. In compound (I), the TMP cation and barbiturate anion are paired through twoN−H···O and one N−H···N hydrogen bonds. This pair further self-organizes through N−H···O hydrogen bonds to generate an array of six hydrogen bonds. These arrays are further cross-linked by N−H···O hydrogen bonds forming a sheet-like structure. The water molecule is also embedded in the sheet via O−H···O and C−H···O hydrogen bonds, forming a rosette-like supramolecular motif. TMP cations are also bridged by alternating water molecules via C−H···O and O−H···N hydrogen bonds. In compound (II), the symmetrical barbiturate anions self-organize on both sides through N−H···O hydrogen bonds generating a supramolecular chain. These chains are cross-linked by the three water molecules. A pair of barbiturate anions and two water molecules constitute an array of four hydrogen bonds (DADA quadruple array). These arrays are cross-linked by another water molecule. 2-Amino-4,6-dimethylpyrimidine cations are paired through N−H···N hydrogen bonds. These pairs are bridged by three water molecules generating a supramolecular ribbon. The barbiturate chains and base pairs are arranged in an alternate manner via N−H···O and O−H···O hydrogen bonds to generate a 3-D network.     

Synthesis and crystal structure of bis(benzimidazolium) tetrahalocobaltate(II)

The crystal structures of benzimidazolium tetrahalocobaltates (HBz)₂[CoX₄] (X = Cl and Br) have been determined. The chloride salt is triclinic, P-1, with a = 7.670(3) Å, b = 8.307(3) Å, c = 15.730(2) Å, and = 87.37(3)°, = 84.99(3)°, = 67.72(2)°. The bromide salt is monoclinic, C2/c, with a = 15.568(2) Å, b = 8.063(3) Å, c = 5.762(2) Å and = 91.36(3)°. The structures of the two salts are closely related. Both the compounds contain isolated tetrahedral CoX₄ ^2– anions and benzimidazolium cations. In the chloride salt, three chloride ions are involved in strong hydrogen bonding while only two bromide ions participate in the bromide salt. The greater deviation from the ideal tetrahedral geometry in CoBr₄ ^2– can be related to the less extensive hydrogen-bonding network compared to the chloro complex.     

Hydrogen bonding patterns in bis(pyrimethamine hydrogen sulfate) monohydrate

The crystal structure of the compound bis [2,4-diamino-5-(p-chlorophenyl)-6-ethyl pyrimidinium hydrogen sulfate] monohydrate was studied by X-ray diffraction methods. The compound crystallises in orthorhombic system, space group P2₁2₁2₁, a=18.531(2) ?, b=16.190(2) ?, c=10.777(2) ?, V=3233.3(8), Z=4. The asymmetric unit shows the presence of two crystallographically independent pyrimethamine molecules, two hydrogen sulfate anions, and a water molecule. The hydrogen sulfate anions form a cyclic hydrogen bonded motif R₂ ²(8) with the 2-amino pyrimidine of the respective protonated pyrimethamine cations, through N–H···O hydrogen bonds. Thus the sulfate anions mimic the role of carboxylate anions observed in many aminopyrimidine-carboxylate interactions. This motif self assembles through DDAA array of quadruple hydrogen bonds, N–H···Cl, O–H···O and C–H···O hydrogen bonds.Supplementary material CCDC-293607 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge at www.ccdc.cam.ac.uk/conts/retrieving.html [or from the Cambridge Crystallographic Data Centre (CCDC), 12 Union Road, Cambridge CB2 IEZ, UK; fax: C44 (0) 1223-336033; e-mail: deposit@ccdc.cam.ac.uk].