Cycloaddition reactions of dichlorodithionitronium hexafluoroarsenate(V) with alkynes and alkenes; the preparation and X-ray crystal structure of 1,3-dichloro-1,3,2-dithiazolidinium hexafluoroarsenate(V)

1990 ◽  
Vol 68 (6) ◽  
pp. 852-862 ◽  
Author(s):  
Simon Parsons ◽  
Jack Passmore ◽  
Melbourne J. Schriver ◽  
Peter S. White

The dichlorodithionitronium cation, ClSNSCl+, undergoes symmetry-allowed, concerted, cycloaddition reactions with alkynes and alkenes in liquid sulphur dioxide. With ethyne and propyne it gives corresponding 1,3,2-dithiazolium salts in quantitative yield. Cycloaddition with alkenes yields (hitherto unknown) 1,3-dichloro-1,3,2-dithiazolidinium cations. The reactions are sensitive to substituents, and only the cycloaddition with ethene occurs quantitatively on a preparative scale. Cycloadditions with propyne and E- and Z-2-butene have been observed in solution. The preparation, characterization, and X-ray crystal structure of the product of the reaction of CISNSCl+ with ethene, 1,3-dichloro-1,3,2-dithiazolidinium hexafluoroarsenate(V), are reported. Crystals of 1,3-dichloro-1,3,2-dithiazolidinium hexafluoroarsenate(V) are monoclinic, of space group P21/c, a = 6.3161(6) Å, b = 17.1724(23) Å, c = 19.1558(18) Å, and β = 98.143(8)°; Z = 4 and R = 0.061. The 1,3-dichloro-1,3,2-dithiazolidinium cation consists of a five-membered [Formula: see text]ring, axially substituted at the sulphurs by chlorine (average bond lengths: S—N 1.603(8) Å, S—Cl 2.025(4) Å, S—C 1.822(10) Å, and C—C 1.504(13) Å). Two crystallographically unique cations are linked by weak S..N contacts into pseudo-dimers. These data are used, together with structural comparisons with related SNS-containing cations and the sulphoxides and the 14N chemical shift, to show that the bonding in the SNS region of the cation is best represented by the valence canonicals [Formula: see text] and [Formula: see text], such that the sulphur and nitrogen atoms respectively carry absolute positive and negative charges. This picture is also supported by the fluoride contacts to the cation from the AsF6−anion, which are exclusively to sulphur. Nuclear magnetic resonance data were consistent with the retention of the solid state structure of [Formula: see text] in solution. Keywords: sulphur-nitrogen chloride, sulphur-nitrogen cations, 1,3-dichloro-1,3,2-dithiazolidinium, cycloaddition reactions, X-ray crystallography.

1983 ◽  
Vol 61 (11) ◽  
pp. 2611-2615 ◽  
Author(s):  
F. W. B. Einstein ◽  
C. H. W. Jones ◽  
T. Jones ◽  
R. D. Sharma

The structure of (Ph3Sn)2Te has been determined by X-ray crystallography. The compound crystallizes in the space group C2/c with a = 18.578(3) Å, b = 7.731(1) Å, c = 25.272(4) Å, β = 117.17(1)°, ρc = 1.702 g cm−3, ρo(CHCl3/CH2I2) = 1.69 g cm−3, and Z = 4. Intensities were measured for 2853 independent reflections (2θ ≤ 50°) of which 2044 were observed (I ≤ 2.3σ(I)) and used in subsequent refinement (final R values were R = 0.034 and Rw = 0.045). The (Ph3Sn)2Te molecule exhibits a "bent" structure in which Sn—Te—Sn = 103.68(2)° and Te—Sn = 2.7266(6) Å and in which the Te atom lies on a crystallographic two-fold axis. Comparison of the present structure with corresponding selenide and sulphide analogues indicates that in all three cases the environment about tin corresponds to that of sp3 hybridisation. The 119Sn Mössbauer quadrupole splittings of (Ph3Sn)3E and (Me3Sn)2E, where E = S, Se, or Te, show a correlation with the 119Sn solution nmr chemical shifts and this correlation is discussed.


1989 ◽  
Vol 67 (11) ◽  
pp. 1687-1692 ◽  
Author(s):  
James P. Johnson ◽  
Gregory K. MacLean ◽  
Jack Passmore ◽  
Peter S. White

The crystal structure of Te(N3)3SbF6 containing the first binary tellurium–nitrogen cation, triazidotellurium(IV) (Te(N3)3+), has been determined by X-ray crystallography. Single crystals of Te(N3)3SbF6 are monoclinic, space group P21/c with a = 9.201(6), b = 8.445(4), c = 13.582(7) Å, β = 100.36(5)°, Z = 4, final R1 = 0.036 for 1286 observed reflections. The structure consists of discrete Te(N3)3+ cations and distorted octahedral SbF6− anions, with some cation–anion interactions. The average Te—Nα—Nβ—Nγ bond distances in Te(N3)3+ are Te—Nα, 1.994(7); Nα—Nβ, 1.237(11); and Nβ—Nγ, 1.116(12) Å. The average bond angles about the Te, Nα, and Nβ atoms are 94.1(3)°, 116.5(6)°, and 173.7(9)°. Structural correlations with other TeX3+ species have yielded an estimate of the electronegativity of the N3− group to be 3.1 ± 0.1. Keywords: tetratellurium (2+) cation, triazidotellurium(IV) cation, electronegativity, azide.


1999 ◽  
Vol 23 (9) ◽  
pp. 578-579
Author(s):  
Rainer Schobert ◽  
Hermann Pfab ◽  
Jutta Böhmer ◽  
Frank Hampel ◽  
Andreas Werner

Racemates of (η3-allyl)tricarbonyliron lactone complex Fe(CO)3{η1:η3-C(O)XCH2CHCMeCH2} 1a (X = O) and (η3-allyl)tricarbonyliron lactam complex 2a (X = NMe) are resolved on a preparative scale by HPLC on cellulose tris(3,5-dimethylphenyl)carbamate/silica gel RP-8 and the absolute configuration of (-)-2a is determined by X-ray crystal structure analysis.


1983 ◽  
Vol 38 (4) ◽  
pp. 426-427 ◽  
Author(s):  
Arndt Simon ◽  
Karl Peters ◽  
Harry Hahn

Abstract The structure of the title compound has been determined by X-ray crystallography. The title compound is synthesized from the elements at 600 °C. Its crystal structure, derived from powder data [3] is refined by single crystal diffractometer data. The structure is trigonal (P3̅ml, α = 684.1(1), c = 724.4(1) pm); Pd2+ cations and PS43- anions form a network with an anti-Claudetite (AS2O3) type structure. The PS4 units are distinctly distorted from ideal tetrahedral symmetry. The Pd atoms have a planar environment of 4 S atoms.


2012 ◽  
Vol 16 (01) ◽  
pp. 154-162 ◽  
Author(s):  
Edwin W.Y. Wong ◽  
Daniel B. Leznoff

The reduction of magnesium phthalocyanine (MgPc) with 2.2 equivalents of potassium graphite in 1,2-dimethoxyethane (DME) gives [K2(DME)4]PcMg(OH)(1) in 67% yield. Compound 1 was structurally characterized using single crystal X-ray crystallography and was found to be a monomeric, heterometallic complex consisting of a μ3-OH ligand that bridges a [MgIIPc3-]- anion to two potassium cations solvated by four DME molecules. An absorption spectrum of 1 confirms the Pc ligand is singly reduced and has a 3–charge. The solid-state structure of 1 does not indicate breaking of the aromaticity of the Pc ligand. Compound 1 is only the second Pc3- complex and the first reduced MgPc to be isolated and structurally characterized.


2011 ◽  
Vol 396-398 ◽  
pp. 2338-2341
Author(s):  
Xing Chuan Wei ◽  
Zhi Li Liu ◽  
Kun Zhang ◽  
Zhi Yun Du ◽  
Xi Zheng

In this paper, (2E,6E)-2,6-Bis(2,3,4-tri-methoxy -benzylidene)cyclohexanone (omitted as tmbcho) (1) was obtained by the reaction of acetic acid, tetrahydrofuran, cyclohexanone and 2,3,4-tri-methoxy-benzaldehyde. Three non-classic hydrogen bonds were observed in the compound. X-ray crystallography shows that the crystal structure is stabilized by intermolecular C-H•••π interactions and it contains plenty of conjugated double bonds. The title compound was characterized by UV-vis and fluorescent spectral studies.


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 62 (9) ◽  
pp. 1133-1138 ◽  
Author(s):  
Veli T. Kasumov ◽  
Ibrahim Uçar ◽  
Ahmet Bulut ◽  
Fevzi Kösal

The coordination chemistry of N-(2,6-di-methylphenyl)-2-hydroxy-3-methoxybenzaldimine (1) with Cu(II) has been investigated by X-ray crystallography, electronic and EPR spectroscopies, as well as by electro- and magnetochemistry. The title complex 2 crystallizes in the orthorhombic space group P212121 (a = 8.1538, b = 17.7466, c =19.8507 Å). The mononuclear square-planar molecules 2 featuring trans-N2O2 coordination are connected via weak intermolecular C-H· · ·π interactions into infinite chains parallel to the a axis. Although the intermolecular Cu· · ·Cu separations within individual chains and between chains are very long (8.154 and 9.726 Å ), the exchange interaction parameter G = 2.03 < 4, estimated from solid state EPR spectra, suggests the existence of long-distance superexchange pathways between adjacent Cu(II) centers. The electronic and electrochemical features of the compound are also discussed.


2006 ◽  
Vol 61 (6) ◽  
pp. 699-707 ◽  
Author(s):  
Daniela John ◽  
Alexander Rohde ◽  
Werner Urland

The gadolinium(III) trifluoroacetates ((CH3)2NH2)[Gd(CF3COO)4] (1), ((CH3)3NH)[Gd(CF3 COO)4(H2O)] (2), Gd(CF3COO)3(H2O)3 (3) as well as Gd2(CF3COO)6(H2O)2(phen)3 · C2H5OH (4) (phen = 1,10-phenanthroline) were synthesized and structurally characterized by X-ray crystallography. These compounds crystallize in the space group P1̅ (No. 2, Z = 2) (1, 2 and 4) and P 21/c (No. 14, Z = 4) (3), respectively, with the following lattice constants 1: a = 884.9(2), b = 1024.9(2), c = 1173.1(2) pm, α = 105.77(2), β = 99.51(2), γ = 107.93(2)°; 2: a = 965.1(1), b = 1028.6(1), c = 1271.3(2) pm, α = 111.83(2), β = 111.33(2), γ = 90.44(2)°; 3: a = 919.6(2), b = 1890.6(4), c = 978.7(2) pm, β = 113.94(2)°; 4: a = 1286.7(8), b = 1639.3(8), c = 1712.2(9) pm, α = 62.57(6), β = 84.13(5), γ = 68.28(5)°. The compounds consist of Gd3+ ions which are bridged by carboxylate groups either to chains (1 and 2) or to dimers (3 and 4). In addition to the Gd3+ dimers, compound (4) also contains monomeric Gd3+ units. The magnetic behaviour of 2 and 3 was investigated in a temperature range of 1.77 to 300 K. The magnetic data for these compounds indicate weak antiferromagnetic interactions


1980 ◽  
Vol 58 (17) ◽  
pp. 1821-1828 ◽  
Author(s):  
Gary D. Fallon ◽  
Bryan M. Gatehouse ◽  
Allan Pring ◽  
Ian D. Rae ◽  
Josephine A. Weigold

Ethyl-3-amino-2-benzoyl-2-butenoate crystallizes from pentane as either the E (mp 82–84 °C) or the Z-isomer (mp 95.5–96.5 °C). The E isomer is less stable, and changes spontaneously into the Z, which bas been identified by X-ray crystallography. The structure is characterised by an N–H/ester CO hydrogen bond and a very long C2—C3 bond (1.39 Å). Nuclear magnetic resonance methods have been used to measure the rate of [Formula: see text] isomerization at several temperatures, leading to the estimate that the free energy of activation at 268 K is 56 ± 8 kJ.


Sign in / Sign up

Export Citation Format

Share Document