Tris(N,N-dialkyldithiocarbamato-S,S')thiotungsten(VI) Complexes and the X-Ray Crystal Structure of [WS(S2CNEt2)3]BF4

1994 ◽  
Vol 47 (11) ◽  
pp. 2075 ◽  
Author(s):  
CG Young ◽  
TO Kocaba ◽  
M Sadek ◽  
RTC Brownlee ◽  
ERT Tiekink
Keyword(s):  
Variable Temperature ◽  
The Other ◽  
Axial Position ◽  
Monoclinic Space Group ◽  
Equatorial Position ◽  
Full Matrix ◽  
X Ray ◽  
X Ray Crystallography ◽  
Dithiocarbamate Ligand ◽  
R Value

The orange, diamagnetic compounds [WS(S2CNR2)3]X(R = Me, X- = BF4-, BPh4-;R = Et, X- =BF4-) were prepared by reacting WSCl4 and Me3SiS2CNR2 in dichloromethane, followed by metathesis with NaX in methanol. The compounds were characterized by elemental analysis, infrared and variable-temperature 1H n.m.r. spectroscopy and X-ray crystallography. Crystals of [WS(S2CNEt2)3] BF4 were monoclinic, space group P21/a with a 12.293(1), b 17.229(5), c 14.257(2) Ǻ,β 113.69(1)°, V 2765(2) Ǻ3 and Dc = 1.796 g cm-3 for Z = 4. The structure was solved by the Patterson method and refined by a full-matrix least-squares procedure, 3961data being used, to a conventional R value of 0.039 ( Rw = 0.040). The seven-coordinate cation possesses a pentagonal-bipyramidal geometry; the terminal thio ligand [W=S 2.127(2)Ǻ] occupies an axial position, a unique dithiocarbamate ligand spans the other axial position and an equatorial position while the two other dithiocarbamate ligands occupy the four remaining equatorial sites.

Crystal Structures of (3S*,4S*,5S*,6S*)-3,4-Epoxy- 1,7-dioxaspiro[5.5]undecan-5-ol, (3R*,5S*,6S*)-1,7- Dioxaspiro[5.5]undecane-3,5-diyl Diacetate and (4S*,5S*,6S*)-1,7-Dioxaspiro[5.5]undecane-4,5-diol

1997 ◽  
Vol 50 (2) ◽  
pp. 123
Author(s):  
Margaret A. Brimble ◽  
Andrew Johnston ◽  
Trevor W. Hambley ◽  
Peter Turner
Keyword(s):  
Hydrogen Bonding ◽  
Hydroxy Group ◽  
Axial Position ◽  
Monoclinic Space Group ◽  
Equatorial Position ◽  
Intermolecular Hydrogen Bonding ◽  
Orthorhombic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray Crystallography

The structures of (3S*,4S*,5S*,6S*)-3,4-epoxy-1,7-dioxaspiro[5.5]undecan-5-ol (2), (3R*,5S*,6S*)-1,7- dioxaspiro[5.5]undecane-3,5-diyl diacetate (4) and (4S*,5S*,6S*)-1,7-dioxaspiro[5.5]undecane-4,5-diol (5) have been determined by X-ray crystallography. The unsubstituted tetrahydropyran ring in (2) adopts an axial position with respect to the epoxy-substituted ring and the hydroxy group at C5 is syn to the epoxide group. Intermolecular hydrogen bonding is observed between the C5 hydroxy group and O1. The two six-membered rings in (4) adopt chair conformations and the two acetate groups adopt 1,3-diaxial positions. The C5 hydroxy group in (5) assumes an axial position anti to the C-O bond of the neighbouring ring whilst 4-OH occupies an equatorial position. Intermolecular hydrogen bonding is also observed between 4-OH and 5-OH. Compound (2), C9H14O4, M 186·21, crystallized in the monoclinic space group P 21/c with a 7·867(1), b 12·2060(9), c 9·3676(8) Å, b 102·744(8), V 877·4(1) Å 3 and No 1163 [I > 2·5s (I)], R 0·031, Rw 0·035. Compound (4), C13H20O6, M 272·30, crystallized in the triclinic space group P 1 with a 9·902(1), b 11·0024(9), c 6·9183(5)Å, a 104·078(8), b 96·769(9), g 101·980(8), V 703·8(1) Å 3 , No 1657 [I > 2·5s(I)], R 0·047, Rw 0·044. Compound (5), C9H16O4, M 188·22, crystallized in the orthorhombic space group Pbca with a 25·504(3), b 8·909(2), c 8·038(2) Å, V 1826·4(5) QA 3 , No 1096 [I > 2·5s(I)], R 0·030, Rw 0·030.

The crystal and molecular structure of a compound containing a novel ring system:(E)-6-(bromomethylene)-5,6-dihydro-4,4-dimethyl-2-phenyl-4H-1,3,4-oxadiazinium bromide

1979 ◽  
Vol 57 (23) ◽  
pp. 3157-3159 ◽  
Author(s):  
Doris Margaret Thompson ◽  
Ian David Brindle ◽  
Mary Frances Richardson
Keyword(s):  
Crystal And Molecular Structure ◽  
Ring System ◽  
The Other ◽  
Monoclinic Space Group ◽  
Single Bond ◽  
X Ray Diffraction ◽  
Full Matrix ◽  
X Ray ◽  
R Factor ◽  
Methylene Group

The crystal structure of (E)-6-(bromomethylene)-5,6-dihydro-4,4-dimethyl-2-phenyl-4H-1,3,4-oxadiazinium bromide has been determined by single crystal X-ray diffraction methods. The crystals are monoclinic, space group P21/c, with a = 12.002(5), b = 6.414(4), c = 17.881(7) Å, β = 101.42(7)°, and Z = 4 formula units of C12H14N2OBr2. The structure was refined by full-matrix least-squares analysis to a conventional R-factor of 0.0491 for 1019 observed reflections. The oxadiazinium ring is in the half-chair form, with the methylene group out of the plane defined by the other five atoms. The C—O bond distances in the ring are somewhat shorter than the distance observed for a carbon–oxygen single bond, suggesting that some delocalization of electron density occurs over part of the ring.

Addition of Alkynes to the Metal-Metal Double Bond in (η-C5Me,5)2Rh2(µ-CO)2; Crystal and Molecular Structure of the Complex (η-C5Me5)2Rh2(µ-CO){µ-C(O)C2(CF3)2}.

1985 ◽  
Vol 38 (2) ◽  
pp. 273 ◽  
Author(s):  
RS Dickson ◽  
GS Evans ◽  
GD Fallon
Keyword(s):  
Room Temperature ◽  
Variable Temperature ◽  
Heavy Atom ◽  
The Other ◽  
Monoclinic Space Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arene Complex ◽  
Metal Metal ◽  
Rhodium Atom

Various alkynes (EtC2Et, MeO2CC2CO2Me, CF3C2CF3, PhC2Ph, C6F5C2C6F5, PhC2Me, PhC2C6-F5, PhC2CO2Me) react with (η-C5Me5)2Rh2(μ-CO)2 in acetone at room temperature; no reaction was observed with ButC2But. The σ-bridging alkyne complex, trans-(η-C5Me5)2Rh2(CO)2(μ-η1:η1C6F5C2C6F5), was obtained from the reaction with C6F5C2C6F5. With the other alkynes, dimetallaeneone complexes, (η-C5Me5)2Rh2(μ-CO){μ-η2:η2-C(O)C2RR′}, are formed. Some of these 'eneone' complexes co-exist with (η- C5Me5)2Rh2(CO)2(μ-η1:η1-RC2R�) in the solid state (RC2R� = PhC2C6F5) and/or in solution (EtC2Et, CF3C2CF3, PhC2C6F5); others (MeO2CC2CO2Me, PhC2Ph, PhC2Me, PhC2CO2Me) exist exclusively as (η-C5Me5)2Rh2(μ-CO){μ-η2:η2- C(O)C2RR′} in both the solid and solution states. The geometry of the bridging group in (η-C5Me5)2Rh2(μ-CO){μ-η2:η2-C(O)C2(CF3)2} has been determined from an X-ray diffraction study. The compound crystallizes with four molecules in the monoclinic space group P21/n in a unit cell of dimensions a 9.451(4), b 15.287(5), c 18.821(8)Ǻ, β 98.66(5)°. The structure was solved by conventional heavy atom methods and refined to R 0.066 based on 4356 observed reflections above background. The structure contains a metalla-eneone ring, Rh -C(=O)-C(CF3)=C(CF3), with the alkene bond η2-attached to the second rhodium atom. Variable temperature N.M.R . measurements establish that the complexes (η- C5Me5)2Rh2(μ-CO){μ-η2:η2-C(O)C2R2}(R = CF3 or CO2Me) are fluxional in solution. Facile cleavage of a C(O)-C(R) bond enables the metalla-eneone ring to shift rapidly from one rhodium atom to the other. Other products formed in the reactions between (η-C5Me5)2Rh2(μ-CO)2 and RC2R′ include. (η-C5Me5) Rh {C4(CF3)4CO}, (η-C5Me5) Rh (η4-C6R6) (R = CF3 or CO2Me), (η-C5Me5)2Rh2-(C4R2R′2) (R = R′ = CO2Me; or R, R′ = Ph, C6F5), (η- C5Me5)2Rh2(CO2C2Ph2), (η-C5Me5)- Rh (C4Ph4CO2), (η-C5Me5)2Rh2(CO)2{C4(CF3)4}, (η-C5Me5)2Rh2(CO)(μ-CO){COC4(C6F5)4} and C6R3R′3 (R = R′ = Ph or CO2Me; R = Ph and R′ = Me). Reactions between (η-C5Me5)2-Co2(μ-CO)2 and alkynes at room temperature or above yield mononuclear cyclopentadienone complexes (η-C5Me5)Co{C4R4CO}(R = Me, CF3 or C6F5), and the mononuclear arene complex (η-C5Me5)Co{C6(CF3)6}.

Synthesis, characterization, and single crystal X-ray structures of [CoIII(acacen)(thioacetamide)2]ClO4 and [CoIII((BA)2en)(thioacetamide)2]PF6 — Solvatochromic properties of [CoIII(acacen)(thioacetamide)2]ClO4

2005 ◽  
Vol 83 (12) ◽  
pp. 2073-2081 ◽  
Author(s):  
Mehdi Amirnasr ◽  
Vratislav Langer ◽  
Nahid Rasouli ◽  
Mehdi Salehi ◽  
Soraia Meghdadi
Keyword(s):  
Solid State ◽  
Molecular Structures ◽  
Axial Position ◽  
Monoclinic Space Group ◽  
Solid State Method ◽  
X Ray ◽  
X Ray Crystallography ◽  
H Nmr ◽  
Ligand Charge Transfer ◽  
Wavelength Absorption

The trans-[CoIII(acacen)(ta)2]ClO4 (1) and trans-[CoIII((BA)2en)(ta)2]PF6 (2) complexes, where H2acacen = bis(acetylacetone)ethylenediimine, H2(BA)2en = bis(benzoylacetone)ethylenediimine, and ta = thioacetamide, have been synthesized by a solid-state method, and characterized by elemental analyses, IR, UV–vis, and 1H NMR spectroscopy. The crystal and molecular structures of 1 and 2 were determined by X-ray crystallography. Both compounds crystallize in the monoclinic space group P2/n. The ClO4 and PF6 ions are both disordered, ClO4 on a twofold axis in 1 and PF6 on an inversion center in 2. Also bridging N-CH2-CH2-N is disordered in both compounds. The octahedral coordination of Co(III) is slightly distorted in both cases. The thioacetamide ligands are S-bonded and occupy the axial position. The IR, UV–vis, and 1H NMR spectra of the two complexes and their solvatochromic properties are also discussed. The longest wavelength absorption that appears at 517 nm for 1 and at 528 nm for 2 in chloroform is solvent dependent, and is assigned as a metal-mediated ligand-to-ligand charge transfer (LLCT).Key words: solid-state synthesis, thioactamide, Co(III) (Schiff base), crystal structure, solvatochromism, metal-mediated LLCT.

Trimethyl(3-Oxido-1-Oxoinden-2-Yl)Ammonium, a New 1,4-Dipolar Ylide

1986 ◽  
Vol 39 (1) ◽  
pp. 183 ◽  
Author(s):  
E Horn ◽  
GP Jones ◽  
RH Prager ◽  
MR Snow ◽  
AD Ward
Keyword(s):  
Least Squares ◽  
Title Compound ◽  
Dimethyl Acetal ◽  
Chemical Degradation ◽  
Monoclinic Space Group ◽  
Full Matrix ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography

Reaction of isobenzofuran-1(3H)-one ( phthalide ) and its derivatives with dimethylformamide dimethyl acetal in the presence of base gives small amounts (c. 10%)1 of the ylid trimethyl (3-oxido-1-oxoinden-2- yl )ammonium (3). The same compound is formed in higher yield from the corresponding 3-dimethylaminomethyleneisobenzofuran-1(3H)-one. Support for this structure comes from chemical degradation and its mode of synthesis, but relies mainly on X-ray crystallography. The title compound crystallizes as clear prisms in the monoclinic space group P21/n with a 15.992(2), b 9.329(4), c 7.112(3)Ǻ, β 90.15(3)° and Z 4. The structural final refinement of a full-matrix least-squares calculation converged with R 0.044 and Rw 0.045.

Structural Studies of Technetium Complexes. XI. The Crystal Structure of Bis(tetraphenylarsonium) Bis(1,2-dicyanoethenedithiolato)nitridotechnetate(V)

1989 ◽  
Vol 42 (6) ◽  
pp. 875 ◽  
Author(s):  
GA Williams ◽  
J Baldas
Keyword(s):  
Crystal Structure ◽  
Monoclinic Space Group ◽  
Coordination Geometry ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
Apical Position ◽  
Full Matrix ◽  
X Ray ◽  
R Value ◽  
Centrosymmetric Structure

The crystal structure of [AsPh4]2 [ TcN(mnt)2] ( mnt = 1,2-dicyanoethenedithiolate) has been determined by single-crystal X-ray diffraction methods at 21 � 1 C. Crystals are monoclinic, space group Pn , with a 11 369(2), b 15.530(2), c 14.421(3) � , P 97.58(2)�, and Z 2. Full-matrix least-squares refinement gave a final R value of 0.057 for 4232 independent reflections. The technetium atom in the [TcN( mnt )2]2- anion has square-pyramidal coordination geometry with the nitrido ligand in the apical position, Tc =N 1.59(1) � , and four Tc -S bonds with distances varying between 2.367(4) and 2.419(4) �. The Tc =N core is disordered about a pseudo-inversion centre, but unequal occupancies of the disordered sites preclude a centrosymmetric structure.

The crystal and molecular structure of N-(3,4,5-trimethoxycinnamoyl)-Δ3-piperidine-2-one, an amide alkaloid (piperlongumine), C17H19NO5

1986 ◽  
Vol 64 (5) ◽  
pp. 876-880 ◽  
Author(s):  
Tapati Banerjee ◽  
Siddhartha Chaudhuri
Keyword(s):  
Molecular Conformation ◽  
Crystal And Molecular Structure ◽  
Lone Pair ◽  
Monoclinic Space Group ◽  
Boat Conformation ◽  
Carbonyl Groups ◽  
Full Matrix ◽  
X Ray ◽  
X Ray Crystallography ◽  
Intramolecular Hydrogen

The crystals of C17H19NO5 belong to the monoclinic space group P21/n with a = 15.793(3), b = 4.089(4), c = 24.649(5) Å, β = 97.56(3)° V = 157 8(2) Å3, and Z = 4. The structure was solved by MULTAN 78 and refined by full-matrix least-squares to a final R of 0.053 for 1863 observed reflections. X-ray crystallography has revealed that the molecule is the Δ3 isomer and not the Δ5 isomer suggested originally from nmr spectroscopy. The piperidyl nitrogen is sp2 hybridized with its electron lone pair involved in conjugation with the carbonyl groups. The piperidone ring adopts a distorted boat conformation. An interesting feature of the structure is the formation of two C(ethylenic)—H … O(keto) intramolecular hydrogen bonds which stabilize the molecular conformation.

The cycloaddition of norbornadiene to (triphenylphosphoranediyl)aminocyclotrithiatriazene; the crystal and molecular structure of Ph3PN—S3N3•C7H8

1983 ◽  
Vol 61 (9) ◽  
pp. 2062-2067 ◽  
Author(s):  
Stephen W. Liblong ◽  
Richard T. Oakley ◽  
A. Wallace Cordes ◽  
Mark C. Noble
Keyword(s):  
Molecular Structure ◽  
Crystal And Molecular Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Monoclinic Space Group ◽  
Frontier Orbitals ◽  
Full Matrix ◽  
X Ray ◽  
X Ray Crystallography ◽  
Kinetics Of

The reaction of norbornadiene with (triphenylphosphoranediyl)aminocyclotrithiatriazene produces the cycloadduct Ph3PN—S3N3•C7H8. The crystal and molecular structure of this compound has been determined by X-ray crystallography. Crystals of Ph3PN—S3N3•C7H8 are monoclinic, space group P21/c, a = 9.757(1), b = 15.114(1), c = 16.535(2) Å, β = 100.73(1)°, V = 2395.7(9) Å3, and Z = 4. The structure was solved by direct methods and refined by Fourier and full-matrix least-squares procedures to give a final R of 0.040 and Rw of 0.058 for 2620 observed reflections. The structure reveals that the S3N3 ring adds to norbornadiene in an exo fashion via two sulphur atoms. The S3N3 ring adopts a chair conformation with the three ligands occupying axial positions on the same side of the ring. The relative rates of this and other cycloadditions involving SN substrates and olefins are discussed in terms of the energies of the interacting frontier orbitals. The results suggest that HOMO(olefin)–LUMO(SN substrate) interactions control the kinetics of these reactions.

Supramoleküle aus Kronenethern und geminalen Sulfonen: Synthese von vier binären Komplexen und Kristallstruktur von (CH2CH2O)4·2H 2C(SO2C2H5)2/Supramolecules of Crown Ethers with Geminal Sulfones: Synthesis of Four Binary Complexes and Crystal Structure of (CH2CH2O )4·2H2C(SO2C2H5)2

1995 ◽  
Vol 50 (7) ◽  
pp. 1018-1024 ◽  
Author(s):  
Axel Michalides ◽  
Dagmar Henschel ◽  
Armand Blaschette ◽  
Peter G. Jones
Keyword(s):  
Monoclinic Space Group ◽  
Triclinic Space Group ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
H Nmr ◽  
Binary Complexes ◽  
Cyclic Polyethers ◽  
Adjacent Unit ◽  
Methylene Group

In a systematic search for supramolecular complexes involving all combinations of the cyclic polyethers 12-crown-4 (12C4), 15-crown-5 (15C 5), 18-crown-6 (18C 6) and dibenzo- 18-crown-6 (DB -18C6), and the geminal di- or trisulfones H2C(SO 2Me)2, H2C (SO2Et)2 and HC (SO2Me)3-n (SO2Et)n (n = 0 -3 ) , only the following four complexes could be isolated and unequivocally characterized by elemental analysis and 1H NMR spectroscopy: [(12C4){H2C (SO2Et)2}2] (3), [(18C6){H2C (S O2Me)2}] (4), [(DB -18C 6){H2C (SO2Et)2}] (5) and [(D B -18C 6)2{HC (SO2Me )(SO2Et)2}3] (6). The structure of 3 (triclinic, space group P1̄) consists of crystallographically centrosymmetric formula units, in which the disulfone molecules are bonded on each side of the ring by two C -H ··· O(crown) interactions originating from the central methylene group (H···O 213 pm) and from the methylene group of one EtSO2 moiety ( H ··· O 237 pm). Formula units related by translation are connected into parallel strands by a third type of reciprocal C -H ···O bond (H ···O 232 pm) between the second H atom of the central methylene group and a sulfonyl oxygen atom of the adjacent unit. The structure of 4 (monoclinic, space group C2/c) showed severe disorder of the crown ether and could not be refined satisfactorily. Compounds 5 and 6 crystallized as long and extremely thin fibres, indicative of linear-polymeric supramolecular structures; single crystals for X-ray crystallography were not available.

Zirconium complexes of a cyclopentadienyl-amido ligand with a pendant amine donor via amine and alkane elimination

1996 ◽  
Vol 74 (9) ◽  
pp. 1696-1703 ◽  
Author(s):  
Ying Mu ◽  
Warren E. Piers ◽  
Donald C. MacQuarrie ◽  
Michael J. Zaworotko
Keyword(s):  
Lewis Acids ◽  
Methyl Chloride ◽  
Monoclinic Space Group ◽  
One Pot ◽  
Amido Complexes ◽  
X Ray ◽  
X Ray Crystallography ◽  
Zirconium Complexes ◽  
Alkane Elimination

Zirconium complexes of the multidentate ligand CpHNMeSiN(H)R (SiNR = -SiMe2N-t-butyl; NMe = -CH2CH2NMe2, 1) were prepared and characterized via amine and alkane elimination procedures. Reaction of 1 with Zr(NMe2)4 gave a mixture of bis-amido complexes 2 in which the ligand was 1,2 and 1,3 substituted. This mixture was converted to the analogous dichlorides 3 using Me2NH•HCl and 1,3-3 was purified at this stage; alternatively, 1,3-3 was obtained in one pot from 1 and Zr(NMe2)4 in ≈70% yield. Conversion of 1,3-3 to dimethyl compound (CpNMeSiNR)Zr(CH3)2, 1,3-4, was accomplished via reaction of the dichloride with methyllithium; methide abstraction with the Lewis acids B(C6F5)3 and [Ph3C]+[B(C6F5)4]− generated the cationic alkyls [(CpNMeSiNR)Zr(CH3)]+[R′B(C6F5)3]− (R′ = CH3, 6a; C6F6, 6b), which were characterized by NMR spectroscopy. Zirconium complexes containing 1 ligated as its 1,2 isomer were obtained from alkane elimination reactions between 1 and in situ prepared RnZrCl4−n (R = CH3, n = 3; R = CH2SiMe3, n = 2). 1,2-3 and the methyl chloride complex 1,2-(CpNMeSiNR)Zr(CH3)Cl, 5, were obtained in 18 and 30% yield, respectively. Complex 5 was characterized by X-ray crystallography (monoclinic, space group P21/a, a = 9.6951(10) Å, b = 14.3794(16) Å, c = 14.364(3) Å, V = 1990.3(5) Å3, Z = 4, R = 0.046, Rw = 0.041.) Key words: amine elimination, Cp-amido, zirconium complexes.

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