Negative hyperconjugation in hexachloro-3-cyclopentenylaminosulphenyl halides: Preparation and X-ray structure of C5Cl6NSBr and synthesis of C5Cl6NS+AsF6−

1991 ◽  
Vol 69 (6) ◽  
pp. 1022-1027 ◽  
Author(s):  
Allen Apblett ◽  
Tristram Chivers ◽  
James F. Fait ◽  
Rainer Vollmerhaus

The reaction of hexachlorocyclopentadiene with (NSCl)3 at 65 °C in the absence of a solvent produced hexachloro-3-cyclopentenylidenaminosulfenyl chloride, C5Cl6NSCl, in good yield. The derivatives C5Cl6NSX(X = Br, I, C5Cl6N, NPr2i, Ph) were prepared by treatment of C5Cl6NSCl with Me3SiBr, Me3SiI, Ph3Sb, iPr2NH, and Ph2Hg, respectively. The crystal structure of C5Cl6NSBr was determined by X-ray crystallography. Crystals of C5Cl6NSBr are triclinic, space group [Formula: see text] with a = 9.626(2), b = 9.810(2), c = 13.736(2) Å, α = 79.68(1), β = 88.62(1), γ = 74.73(1)°, Z = 4, final R and Rw values were0.075 and 0.063, respectively, for 4850 unique observed reflections. The > C=NSBr moiety adopts a syn conformation and there are two different molecules of C5Cl6NSBr in the asymmetric units. The bond lengths are d(C=N) = 1.278(8) and 1.253(8), d(N—S) = 1.560(6) and 1.569(6), and d(S—Br) = 2.229(2) and2.235(2) Å. The bond angles at nitrogen are 146.7(4) and 148.6(4) and those at sulfur are 116.8(2) and 116.5(2)°. The unusual geometry of the < C=NSBr moiety is explained in terms of negative hyperconjugation (nN → σSBr*). A variable temperature 13C NMR of C5Cl6NSCl provides evidence for a fiuxional process (ΔG*298 = 68.1 ± 1.2 kJ mol−1) in solution. The dark purple compound C5Cl6NS+AsF6− was synthesized from the reaction of C5Cl6NSCl and AgAsF6 in SO2. Key words: hexachloro-3-cyclopentenylidenamino sulfides, crystal structure, hexachloro-3-cyclopentenylidenaminosulfenyl bromide.


2006 ◽  
Vol 62 (7) ◽  
pp. o3046-o3048 ◽  
Author(s):  
Ashley T Hulme ◽  
Philippe Fernandes ◽  
Alastair Florence ◽  
Andrea Johnston ◽  
Kenneth Shankland

A polycrystalline sample of a new polymorph of the title compound, C8H11NO2, was produced during a variable-temperature X-ray powder diffraction study. The crystal structure was solved at 1.67 Å resolution by simulated annealing from laboratory powder data collected at 250 K. Subsequent Rietveld refinement yielded an R wp of 0.070 to 1.54 Å resolution. The structure contains two molecules in the asymmetric unit, which form a C 2 2(8) chain motif via N—H...O hydrogen bonds.



2006 ◽  
Vol 84 (10) ◽  
pp. 1294-1300 ◽  
Author(s):  
Keith Vaughan ◽  
Shasta Lee Moser ◽  
Reid Tingley ◽  
M Brad Peori ◽  
Valerio Bertolasi

Reaction of a series of diazonium salts with a mixture of formaldehyde and 1,2-diamino-2-methylpropane affords the 3-({5,5-dimethyl-3-[2-aryl-1-diazenyl]-1-imidazolidinyl}methyl)-4,4-dimethyl-1-[2-aryl-1-diazenyl]imidazolidines (1a–1f) in excellent yield. The products have been characterized by IR and NMR spectroscopic analysis, elemental analysis, and X-ray crystallography. The X-ray crystal structure of the p-methoxycarbonyl derivative (1c) establishes without question the connectivity of these novel molecules, which can be described as linear bicyclic oligomers with two imidazolidinyl groups linked together by a one-carbon spacer. This is indeed a rare molecular building block. The molecular structure is corroborated by 1H and 13C NMR data, which correlates with the previously published data of compounds of types 5 and 6 derived from 1,3-propanediamine. The triazene moieties in the crystal of 1c display significant π conjugation, which gives the N—N bond a significant degree of double-bond character. This in turn causes restricted rotation around the N—N bond, which leads to considerable broadening of signals in both the 1H and 13C NMR spectra. The molecular ion of the p-cyanophenyl derivative (1b) was observed using electrospray mass spectrometry (ES + Na). The mechanism of formation of molecules of type 1 is proposed to involve diazonium ion trapping of the previously unreported bisimidazolidinyl methane (13).Key words: triazene, bistriazene, imidazolidine, synthesis, X-ray crystallography, NMR spectroscopy.



2007 ◽  
Vol 72 (4) ◽  
pp. 560-568 ◽  
Author(s):  
Goran N. Kaluđerović ◽  
Harry Schmidt ◽  
Christoph Wagner ◽  
Kurt Merzweiler ◽  
Dirk Steinborn

The reaction of solutions of tetraalkyl ethylenediamine-N,N,N',N'-tetraacetate esters (alkyl = Me, 1a; Et, 1b) with H2[PdCl4] led to the complexes [PdCl2(R4EDTA)] (R = Me, 2a; Et, 2b). The coordination of R4EDTA ligands to palladium(II) ions occurs through the two nitrogen donor atoms, as confirmed by IR, 1H and 13C NMR spectroscopies and X-ray crystallography.



2000 ◽  
Vol 55 (9) ◽  
pp. 796-802 ◽  
Author(s):  
H. Kara ◽  
Y. Elerman ◽  
K. Prout

Preparation and magnetic properties of a 3,5-dimethylpyrazolate bridged binuclear copper(II) complex [Cu2(L)(3 ,5 -pyz)] (L = 1,3-Bis(2-Hydroxy-5-Chlorosalicylideneamino)propan- 2-ol) is reported. The crystal structure determined by X-ray diffraction methods. (C22H20N4O3CI2CU2), triclinic, space group P1̄, a = 9.622(3), b = 10.921(2), c = 11.420(3) Å, α = 100.73(2), β = 94.04(2), Υ = 108.08(2)°, V = 1110.2(5) Å3, Z = 2. Two copper(II) ions in a square-planar coordination are bridged via alkoxide oxygen and 3,5-dimethyl pyrozolate nitrogen atoms to form a dinuclear unit. The metal coordination sphere is four-coordinate, planar with an N2O2 donor set. The dihedral angle between the two coordination planes is 166.83°. There are significant intermolecular interactions between neighbouring binuclear entities. The shortest intermolecular Cu (1) ... Cu(1)i distance is 3.383(1) Å and the Cu(1) - O ( 1)i distance is 2.666(3) Å (i = 1 -x, -y, 1 - z). The variable-temperature magnetic susceptibility measurement for a powdered sample of the complex was carried out in the temperature range 5 - 350 K and analysed to obtain values of the parameter J in the exchange Hamiltonian ℋ = -2JScu Scu; 2J = -164 cm-1. The magnetic moment at 300 K is about 2.42 μB, and 0.22 μB at 5 K. The weak antiferromagnetism of the present complex is reasonably explained in terms of the orbital countercomplementary effect based on Hoffmann's theory for super-exchange interaction



2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Xing-Hai Liu ◽  
Jian-Quan Weng ◽  
Cheng-Xia Tan

A new 1,2,3-thiadiazole compound was synthesized and characterized. The crystal structure of the title compound (C15H14FN5S2, Mr = 347.43) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P-1 witha=7.0490(14),b=9.0212(18),c=12.799(3) Å,α= 89.97(3)°,β= 82.27(3)°,γ= 73.17(3)°,V= 771.3(3)  Å3, Z = 2, F(000) = 360, Dc = 1.496 g/cm3,μ= 0.036 mm−1, the finalR1= 0.0358, andwR2= 0.0986 for 2204 observed reflections withI>2σ(I). A total of 5697 reflections were collected, of which 2719 were independent (Rint=0.0028). The herbicidal activity of title compound was determined; the results showed that the title compound displayed excellent fungicidal activity.



2010 ◽  
Vol 65 (2) ◽  
pp. 128-134 ◽  
Author(s):  
Farzin Marandi ◽  
Zahra Nikpey ◽  
Jia Hao Goh ◽  
Hoong-Kun Fun

Three substituted 2,2'-bipyridine adducts of lead(II) thenoyltrifluoroacetonate, [Pb(4,4'-dm-2,2’- bpy)(ttfa)2]2, 1, [Pb(5,5' -dm-2,2’-bpy)(ttfa)2]2, 2, and [Pb(4,4'-dmo-2,2’-bpy)(ttfa)2], 3, (4,4’ -dm- 2,2’-bpy, 5,5’-dm-2,2’-bpy, 4,4’-dmo-2,2’-bpy and ttfa are the abbreviations for 4,4’-dimethyl-, 5,5’-dimethyl-, and 4,4’-dimethoxy-2,2’-bipyridine, and thenoyltrifluoroacetonate, respectively) have been synthesized, characterized by elemental and thermal analysis, IR and 1H- and 13C-NMR spectroscopy, and studied by X-ray crystallography. The supramolecular features in these complexes are guided/controlled by weak directional intermolecular interactions.



2004 ◽  
Vol 59 (3) ◽  
pp. 291-297 ◽  
Author(s):  
Andreas Sofetis ◽  
Giannis S. Papaefstathiou ◽  
Aris Terzis ◽  
Catherine P. Raptopoulou ◽  
Theodoros F. Zafiropoulos

The reaction of Ga2(SO4)3·18H2O and excess 2,2′:6′,2″-terpyridine (terpy) in MeOH / H2O leads to [Ga(OH)(SO4)(terpy)(H2O)]·H2O (1·H2O] in good yield. The structure of the complex has been determined by single-crystal X-ray crystallography. The GaIII atom in 1·H2O is 6-coordinate and ligation is provided by one terdentate terpy molecule, one monodentate sulfate, one terminal hydroxide and one terminal H2O molecule; the coodination polyhedron about the metal is described as a distorted octahedron. There is an extensive hydrogen-bonding network in the crystal structure which generates corrugated layers parallel to bc. The new complex was characterized by IR and 1H NMR spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding



2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Jing Li ◽  
Handong Yin ◽  
Min Hong

The complex dibutyltin 2-oxo-2-phenylacetic acid 4-hydroxybenzohydrazone has been synthesized and characterized by elemental analysis, IR, 1H and 13C NMR, and X-ray single-crystal diffraction studies. The crystal structure belongs to triclinic, space group P-1 with a=9.3220 (10) Å, b=9.8779 (11) Å, c=15.9401 (17) Å, β=97.0930 (10)∘, Z=2, V=1427.6(3) Å3, Dc=1.413 mg/cm3, μ=0.936 mm−1, F(000)=628, R=0.1158, and wR=0.2522. X-ray analysis indicates that O(2), N(2), O(4), and O(4)#1 from the ligand and O(5) from ethanol molecule are in the equatorial positions; the axial positions are occupied by two n-butyl groups. It shows a distorted pentagonal bipyramid configuration with seven-coordination for central tin atom. Fascinatingly, the supramolecular infrastructures are observed, which exist as two-dimensional sheets assembled from the organometallic subunits through intermolecular and intramolecular O–H⋯X or C–H⋯X (X = O or N) hydrogen bonds.



2000 ◽  
Vol 55 (10) ◽  
pp. 966-970 ◽  
Author(s):  
Igor O. Fritsky ◽  
Jolanta Świątek-Kozlowska ◽  
Anatoliy A. Kapshuk ◽  
Henryk Kozłowski ◽  
Tatiana Yu. Sliva ◽  
...  

AbstractThe new mixed metal assembly [Ni(phen)3][Cu(H-1pap)]2(NO3 ) · 8 H2O (2) (H2pap = CH3- C(=NO H)-C(O )-NH-(CH2)3-NH-C(O )-C(=NOH)-CH3) was obtained by co-crystallisation of [Li(H2O)4][Cu(H-1pap)] · 2 H2O (1) and tris(1,10-phenanthroline)nickel(II) nitrate and studied by means of X-ray crystallography (triclinic, space group P1, a = 13.471(3), b = 13.641(3), c = 15.401(3) Å, α = 108.21(3), β = 97.73(3), γ = 107.74(3)°, V = 2476.6(9) Å , Z = 2 ,R1 = 0.0677 for 4672 unique reflections with I > 2σ(I)). The assembly indicates a network structure and consists of isolated cationic and anionic modules (octahedral [Ni(phen)3]2+ and square-planar [Cu(H-1pap)]-), non-coordinated nitrate anions and solvating water molecules. The elements of the crystal structure are linked by interactions of different types: by an extended system of H bonds, stacking interactions between aromatic rings, long apical Cu-N contacts and specific π-π interaction between a deprotonated oxime group of the complex anion and a phenanthroline ligand



1991 ◽  
Vol 44 (2) ◽  
pp. 303 ◽  
Author(s):  
R Bhula ◽  
DC Weatherburn

The crystal structure of [ Mn ( terpy )2](I3)2( terpy = 2,2°:6°,2°-terpyridene) has been determined by X-ray crystallography. The crystals are triclinic, space group Pī , a 9.357(4), b 8.600(2), c 24.531(8) Ǻ, α 93.64(2), B 95.58(3), γ 91.52(2)°, Z 2, V 1960(1)Ǻ3. The structure has been refined to a residual R of 0.065 (Rw 0.070). The coordination sphere of the metal ion is distorted octahedral with each terpy ligand coordinated in a meridional fashion. The structure is compared with those of other M( terpy )2n+ complexes formed by first-row transition metal ions.



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