Synthesis and Structural Characterization of N-[4-(2-Hydroxyethyl)-1,2,4-oxathiazinan-3-ylidene]-benzamide and its Mercury(II) Chloride Adduct

2005 ◽  
Vol 60 (9) ◽  
pp. 945-950 ◽  
Author(s):  
Jorge R. Angulo-Cornejo ◽  
Ketty Ayala-León ◽  
Gabriel García Herbosa ◽  
José V. Cuevas ◽  
Virginia Diez ◽  
...  
Keyword(s):  
Structural Characterization ◽  
Variable Temperature ◽  
Molecular Mechanic ◽  
Chair Conformation ◽  
Boat Conformation ◽  
X Ray ◽  
H Nmr ◽  
Conformational Interconversion ◽  
Chloride Adduct

The synthesis of N-[4-(2-hydroxyethyl)-1,2,4-oxathiazinan-3-ylidene]-benzamide (2a) and N-[4- (2-hydroxyethyl)-1,2,4-oxathiazinan-3-ylidene]-2-fluorobenzamide (2b) by oxidation of the corresponding 1,1-bis(2-hydroxyethyl)-3-aroylthioureas with potassium iodate in aqueous solution is reported. Variable temperature 1H NMR spectra of 2a prove that the heterocyclic 1,2,4-(O, S,N) sixmembered ring is involved in a dynamic chair-boat conformational interconversion. Molecular mechanic calculations show that the chair conformation is more stable than the boat conformation by 3.0 kcal/mol. The synthesis of the adduct [(2a)·0.5 HgCl2] 3 as well as the X-ray structural characterization of 2a and 3 are also reported.

Iridium(I) complexes containing bidentate pyrazolylgallate ligands. X-ray crystal structures of [Me2Gapz2]Ir(COD), [Ir(μ-pz)(CO)2]2, and [Ir(μ-3,5-Me2pz)(CO)2]2

1985 ◽  
Vol 63 (3) ◽  
pp. 692-702 ◽  
Author(s):  
Sophia Nussbaum ◽  
Steven J. Rettig ◽  
Alan Storr ◽  
James Trotter
Keyword(s):  
Crystal Structures ◽  
Variable Temperature ◽  
Hydrogenation Reaction ◽  
Synthesis And Characterization ◽  
Nmr Studies ◽  
X Ray ◽  
H Nmr ◽  
Measurable Activity

The synthesis and characterization of a number of Ir(I) complexes incorporating bidentate, chelating, pyrazolylgallate ligands are described. Non-rigidity for some of the complexes in solution has been demonstrated by variable temperature 1H nmr studies. Crystal structures of three complexes, [Me2Gapz2]Ir(COD), [Ir(μ-pz)(CO)2]2, and [Ir(μ-3,5-Me2pz)(CO)2]2 are reported and confirm the expected boat conformations for the six-membered M—(N—N)2—Ir rings (where M = Ir or Ga) in the compounds. One of the complexes studied has exhibited measurable activity as a catalyst in the hydrogenation reaction of cyclohexene.

Synthesis and characterization of 2,2-diphenyl-1-(5-acetonyl-2,4,6-trinitro-1,3-cyclohexadienyl)hydrazine, C21H19N5O7

1993 ◽  
Vol 71 (7) ◽  
pp. 1057-1063 ◽  
Author(s):  
Donna L. Draper ◽  
Richard J. Barton ◽  
Beverly E. Robertson ◽  
Barbara R. Nelson ◽  
John A. Weil
Keyword(s):  
Nitro Group ◽  
Synthesis And Characterization ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Phenyl Rings ◽  
Common Plane ◽  
Twist Boat

The reaction of 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazine with the enolate of acetone, followed by acidification, yields the title compound 2,2-diphenyl-1-(5-acetonyl-2,4,6-trinitro-1,3-cyclohexadienyl)hydrazine, C21H19N5O7. The identity of the latter was confirmed by a combination of mass spectrometry, FTIR, elemental analysis, and 1H NMR. Crystals were grown from dichloromethane –95% ethanol and the structure was determined by X-ray diffraction. Crystals are monoclinic, P21/c, a = 9.254(3), b = 13.531(3), c = 17.39(5) Å, β = 106.18(2)° at 225 K. R = 0.073, Rω = 0.038 for reflections with I > 2σ(I). The Zachariasen extinction factor, g, refined to 18(3) × 10−4. The cyclohexadiene ring is puckered with a primarily twist-boat conformation. Atoms C(1) to C(3), C(6), the nitro group on C(2), and the hydrazine moiety (N(8)—N(7)—H(7) attached to C(1)) all lie close to a common plane. The planes of the two phenyl rings, the acetonyl substituent, and the C(6) nitro group are each roughly perpendicular to this plane. The C(5) acetonyl and C(6) nitro groups are trans to each other.

Synthesis, characterization, and dynamic behaviour of pseudoferrocene complexes

1990 ◽  
Vol 68 (11) ◽  
pp. 1923-1931 ◽  
Author(s):  
Michael D. Clerk ◽  
Michael J. Zaworotko ◽  
Bozena Borecka ◽  
T. Stanley Cameron ◽  
Donald L. Hooper ◽  
...  
Keyword(s):  
Dynamic Behaviour ◽  
Variable Temperature ◽  
Grignard Reagents ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
X Ray ◽  
H Nmr ◽  
Ring Rotation ◽  
Methyl Phenyl

Carbanion sources (organolithium and Grignard reagents) react with [(mesitylene)2Fe]2+ and [(mesitylene)(Ch)Fe]+ cations (Ch = cyclohexadienyl) to afford neutral Ch2Fe and ChCh′Fe ("pseudoferrocene") complexes, respectively. Addition of R− (R− = methyl, phenyl, benzyl, and t-butyl) occurs stereospecifically via exo addition at an unsubstituted carbon atom of the arene ring. The synthesis and characterization of these complexes is detailed and the structure of bis(η5-exo-6-phenyl-1,3,5-trimethylcyclohexadienyl)iron(II), 3b, has been determined by single crystal X-ray diffraction analysis. 3b crystallizes in the triclinic space group [Formula: see text], with a = 11.947(2), b = 12.784(1), c = 8.865(2), α = 108.59(1)°, β = 108.19(1)°, γ = 84.91(1)°, and Dcalcd 1.227 g cm−3 for Z = 2. Least-squares refinement gave a conventional R value of 0.0452 for 2080 independent observed reflections. The structure reveals that the complex adopts a gauche-eclipsed conformation. The variable temperature (vt) 1H NMR spectra of pseudoferrocenes are interpreted in terms of restricted ring rotation around the ligand—metal—ligand axis. Keywords: arene, cyclohexadienyl, pseudoferrocene, variable temperature NMR, X-ray diffraction.

New horizons for the structural characterization of stainless steel slags by X-ray powder diffraction

2007 ◽  
Vol 2007 (suppl_26) ◽  
pp. 61-66 ◽  
Author(s):  
B. Peplinski ◽  
B. Adamczyk ◽  
G. Kley ◽  
K. Adam ◽  
F. Emmerling ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Powder Diffraction ◽  
Structural Characterization ◽  
X Ray ◽  
New Horizons

Crystal structure determination of the conformation of two bicyclo[3.3.1]nonan-ones

1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen
Keyword(s):  
Crystal Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Molecular Structures ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Final Agreement

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.

scholarly journals Structural Characterization of Heterodinuclear ZnII-LnIII Complexes (Ln = Pr, Nd) with a Ring-Contracted H2valdien-Derived Schiff Base Ligand

2021 ◽  
Author(s):  
Shabana Noor ◽  
Richard Goddard ◽  
Fehmeeda Khatoon ◽  
Sarvendra Kumar ◽  
Rüdiger W. Seidel
Keyword(s):  
Molecular Structure ◽  
Schiff Base ◽  
Structural Characterization ◽  
Schiff Base Ligand ◽  
Crystal And Molecular Structure ◽  
X Ray ◽  
X Ray Crystallography ◽  
Imidazoline Ring

AbstractSynthesis and structural characterization of two heterodinuclear ZnII-LnIII complexes with the formula [ZnLn(HL)(µ-OAc)(NO3)2(H2O)x(MeOH)1-x]NO3 · n H2O · n MeOH [Ln = Pr (1), Nd (2)] and the crystal and molecular structure of [ZnNd(HL)(µ-OAc)(NO3)2(H2O)] [ZnNd(HL)(OAc)(NO3)2(H2O)](NO3)2 · n H2O · n MeOH (3) are reported. The asymmetrical compartmental ligand (E)-2-(1-(2-((2-hydroxy-3-methoxybenzylidene)amino)-ethyl)imidazolidin-2-yl)-6-methoxyphenol (H2L) is formed from N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) through intramolecular aminal formation, resulting in a peripheral imidazoline ring. The structures of 1–3 were revealed by X-ray crystallography. The smaller ZnII ion occupies the inner N2O2 compartment of the ligand, whereas the larger and more oxophilic LnIII ions are found in the outer O2O2’ site. Graphic Abstract Synthesis and structural characterization of two heterodinuclear ZnII-LnIII complexes (Ln = Pr, Nd) bearing an asymmetrical compartmental ligand formed in situ from N1,N3-bis(3-methoxysalicylidene)diethylenetriamine (H2valdien) through intramolecular aminal formation are reported.

Synthesis and structural characterization of a magnesium phthalocyanine(3–) anion

2012 ◽  
Vol 16 (01) ◽  
pp. 154-162 ◽  
Author(s):  
Edwin W.Y. Wong ◽  
Daniel B. Leznoff
Keyword(s):  
Absorption Spectrum ◽  
Solid State ◽  
Single Crystal ◽  
Structural Characterization ◽  
Heterometallic Complex ◽  
State Structure ◽  
Solid State Structure ◽  
X Ray ◽  
X Ray Crystallography

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.

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