Structural Study of a Binuclear Zinc Complex of 2,6-Diacetylpyridine Bis{N(4)-dimethylthiosemicarbazone}, [Zn(2,6Ac4DM)]2 · MeCN

2001 ◽  
Vol 56 (3) ◽  
pp. 229-232 ◽  
Author(s):  
Elena Labisbal ◽  
Alfonso Castiñeiras ◽  
Christine A. Brown ◽  
Douglas X. West
Keyword(s):  
Nitrogen Atom ◽  
Sulfur Atom ◽  
Electrochemical Synthesis ◽  
Zinc Complex ◽  
The Other ◽  
Acetonitrile Solution ◽  
Monoclinic Space Group ◽  
Pyridyl Nitrogen ◽  
Imine Nitrogen ◽  
Imine Nitrogen Atom

Abstract Zinc, 2,6-Diacetylpyridine Bis{N(4)-dimethylthiosemicarbazone}, Electrochemical Synthesis Zinc metal was oxidized in the presence of 2,6-diacetylpyridine bis{N(4)-dimethylthiosemi-carbazone} (2 ,6H2Ac4DM) in an acetonitrile solution, to produce a complex of the formula [Zn(2 ,6Ac4DM)]2-CH3CN. One of the zinc atoms is distorted octahedrally 6-coordinate and the coordination involves both pyridyl nitrogen atoms of the two ligands, the imine nitrogen atom and the thiolato sulfur atom of one thiosemicarbazone moiety of each ligand. The other zinc center is distorted tetrahedrally 4-coordinate with NS coordination of the two remaining thiosemicarbazone moieties. The complex crystallizes in the monoclinic space group C2/c with a = 14.952(2), b = 17.656(3), c = 15.553(4) Å, ß = 111.456(16)°, V= 3821.5(13) Å3 and Z = 4.

Synthesis and Properties of 2-(Dimesitylboryl)benzylideneamines

2009 ◽  
Vol 64 (11-12) ◽  
pp. 1381-1386 ◽  
Author(s):  
Zureima García-Hernández ◽  
François P. Gabbaï
Keyword(s):  
Excited State ◽  
Nitrogen Atom ◽  
Intramolecular Charge Transfer ◽  
Quantum Yields ◽  
Structural Studies ◽  
Green Fluorescence ◽  
Imine Nitrogen ◽  
Td Dft ◽  
Imine Nitrogen Atom ◽  
Boron Center

Lithiation of 2-(2-bromophenyl)-dioxolane (1) followed by reaction with dimesitylboron fluoride afforded 2-(2-dimesitylborylphenyl)-dioxolane (2) which was deprotected to afford 2- dimesitylboryl-benzaldehyde (3). Compound 3 reacts with aliphatic amines such as n-butylamine and ethanolamine to afford the corresponding imines 2-(dimesitylboryl)benzylidenebutylamine (4) and 2-(dimesitylboryl)benzylideneethanolamine (5), respectively. Structural studies indicate coordination of the imine-nitrogen atom to the boron center. Imines 4 and 5 emit a green fluorescence near 510 nm with quantum yields approaching 10%. TD-DFT calculations suggest that this emission arises from an intramolecular charge-transfer excited state

Synthesis, Characterization and Molecular Structure of 2-Pyridyl-formamide N(4)-Dimethylthiosemicarbazone and Some Five-Coordinated Zinc(II) and Cadmium(II) Complexes

2001 ◽  
Vol 56 (12) ◽  
pp. 1297-1305 ◽  
Author(s):  
Elena Bermejo ◽  
Alfonso Castiñeiras ◽  
Larissa M. Fostiak ◽  
Isabel García ◽  
Antonio L. Llamas-Saiz ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Hydrogen Bonding ◽  
Sulfur Atom ◽  
Hydrogen Bonding Interaction ◽  
Pyridyl Nitrogen ◽  
Zwitterionic Form ◽  
Anionic Ligand ◽  
Imine Nitrogen ◽  
Thiosemicarbazone Ligand ◽  
Bonding Interaction

AbstractSodium in dry methanol reduces 2-cyanopyridine in the presence of N(4)-dimethylthiosemicarbazide to produce 2-pyridyl-formamide N(4)-dimethylthiosemicarbazone, HAm4DM. Com­plexes with zinc(II) and cadmium(II) of formulae [M(Am4DM)(OAc)]2 and [M(HAm4DM)X2] (M = Zn or Cd, X = Cl, Br or I) have been prepared and characterized by spectro­scopic techniques. In addition, the crystal structures of HAm4DM, [Zn(HAm4DM)Br2], and [Cd(HAm4DM)l2] DMSO have been solved. HAm4DM is in the zwitterionic form with a hydrogen bonding interaction between the iminium hydrogen and the thiolato sulfur atom. Co­ ordination of the neutral thiosemicarbazone ligand is via the pyridyl nitrogen, imine nitrogen and thione sulfur atoms, while the anionic ligand in [M(Am4DM)(OAc)]2 coordinates with the same two nitrogen atoms and a thiolato sulfur atom. The [M(HAm4DM)X2] complexes are 5-coordinate with the tridentate thiosemicarbazone and two halogen ligands approaching a square pyramidal stereochemistry.

Preparation and 31P NMR characterization of N-bonded complexes of platinum(II) with a phosphadithiatriazine: X-ray structure of trans-PtCl2(Pet3)(η1-N-Ph2PS2N3)

1992 ◽  
Vol 70 (10) ◽  
pp. 2602-2606 ◽  
Author(s):  
Tristram Chivers ◽  
Robert W. Hilts ◽  
Ian H. Krouse ◽  
A. Wallace Cordes ◽  
Randal Hallford ◽  
...  
Keyword(s):  
Nitrogen Atom ◽  
Free Ligand ◽  
Heterocyclic Ring ◽  
Structural Features ◽  
The Other ◽  
Monoclinic Space Group ◽  
Hydrogen Atoms ◽  
Absorption Bands ◽  
X Ray ◽  
Nmr Characterization

The reaction of Ph2PS2N3 with [Pt2(μ-Cl)2(PEt3)4][BF4]2 or [PtCl2(PEt3)]2, in dichloromethane at 23° C produces the 1:1 adducts cis-[PtCl(PEt3)2(Ph2PS2N3)][BF4], 3, and trans-[PtCl2(PEt3)(Ph2PS3N2)], 4, respectively, in good yields. The 31P NMR data for 3 and 4 indicate that (i) the platinum is attached to a nitrogen atom adjacent to phosphorus in both these adducts, (ii) the PEt3 ligands in 3 are in mutually cis positions, and (iii) the PEt3 ligand in 4 is trans to the heterocyclic nitrogen. These structural features were confirmed by an X-ray analysis of 4. Crystals of 4 are monoclinic, space group P21/c, with a = 14.920(3) Å, b = 8.966(5) Å, c = 19.103(5) Å, β = 109.32(2)°, V = 2411.6(16) Å3, and Z = 4. The least-squares refinement with anisotropic thermal parameters for all non-hydrogen atoms converged at R = 0.050 and Rw = 0.053. The Pt—N bond length is 2.122(15) Å and the coordinated nitrogen atom is lifted ca. 0.63(2) Å out of the plane containing the other heterocyclic ring atoms. The attachment of a platinum(II) centre to the PN3S2 ring perturbs the S—N bond lengths significantly. The S—N distance involving the coordinated nitrogen is 1.672(16) Å, while the other S—N distances are 1.631(19), 1.555(19), and 1.562(19) Å, indicative of a localized sulfur diimide (-N=S=N-) structure. The UV–visible spectra of 3 and 4 in CH2Cl2 exhibit absorption bands at 514 and 528 nm, respectively, but dissociation of these adducts to give the free ligand Ph2PS2N3 occurs readily in dilute solution.

Electrochemical Synthesis of a 6-Coordinate Cadmium(II) Complex with N-Methylisatin N(4)-cyclohexylthiosemicarbazone

2000 ◽  
Vol 55 (2) ◽  
pp. 162-166 ◽  
Author(s):  
Elena Labisbal ◽  
Antonio Sousa ◽  
Alfonso Castiñeiras ◽  
Jose A. García-Vázquez ◽  
Jaime Romero ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Electrochemical Synthesis ◽  
Acetonitrile Solution ◽  
Monoclinic Space Group ◽  
Space Group ◽  
Anionic Ligands ◽  
Cadmium Metal

Abstract Cadmium metal was oxidized in the presence of N-methylisatin N(4)-cyclohexyl-thiosemicarbazone (HMeIs4Chex) in an acetonitrile solution, which produced a complex of the formula [Cd(MeIs4Chex)2]. The two MeIs4Chex ligands are at an angle close to 90° from each other, and there is hydrogen bonding to two adjacent molecules by the anionic ligands remaining NH groups. The complex crystallizes in the monoclinic space group P21/c with a = 11.820(4), b = 11.491(4), c = 27.834(4) Å, β = 106.82(2)°, V = 3618.7(17) Å3 and Z = 4.

Reaktionen von 1,2,4-Thiadiazol-3,5-dicarbonitril mit Schwefelchloriden: Röntgenstrukturanalyse von S3(CN)4Cl2·AsF5 und S3(CN)8Cl2/Reactions of 1,2,4-Thiadiazol-3,5-dicarbonitrile with Sulfur Chlorides: X-Ray Crystal Structure Analysis of S3(CN)4Cl2·A sF5 and S3(CN)8Cl2

1986 ◽  
Vol 41 (2) ◽  
pp. 162-166 ◽  
Author(s):  
Herbert W. Roesky ◽  
Jörg Sundermeyer ◽  
Jürgen Schimkowiak ◽  
Thomas Gries ◽  
Mathias Noltemeyer ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Nitrogen Atom ◽  
Sulfur Atom ◽  
Experimental Error ◽  
Crystal Structure Analysis ◽  
The Other ◽  
Space Group ◽  
X Ray ◽  
Ring Nitrogen

The reactions between 1,2,4-thiadiazol-3,5-dicarbonitrile, S(CN)4, and sulfur chlorides (SCl2 and S2Cl2) in the presence of Adogen® 464 (Aldrich) proceeds with formation of S3(CN)4Cl2 (1) and S3(CN)8Cl2 (2). These main products were characterized by X-ray structure determination of an adduct 1a and of 2. This adduct 1a was obtained by addition of the Lewis acid AsF5 in liquid SO2. 1a crystallizes with one SO2 molecule in the space group P21/n with a = 1177.3(2), b = 1082.8(1), c = 1255.3(5) pm, β = 109.73(3)°, Z = 4, V = 1.5061 nm3. It contains two five-membered rings connected by a nitrogen atom. AsF5 is coordinated to one of the ring nitrogen atoms [N(1)] adjacent to the sulfur atom S(1) and C(1)Cl-group. The other ring contains an S(2)-S(3) bond of length 207.7(4) pm. The rings are planar within experimental error. 2 crystallizes in the space group P21/n with a = 782.12(6), b = 1498.1(5), c = 1217.8(2) pm, β = 102.43(1)°, Z = 4, V = 1.3934 nm3. 2 is formed by addition of one molecule of SCl2 to two molecules of S(CN)4.

scholarly journals New Molybdenum(II) Complexes with α-Diimine Ligands: Synthesis, Structure, and Catalytic Activity in Olefin Epoxidation

Molecules ◽  
2019 ◽  
Vol 24 (3) ◽  
pp. 578 ◽  
Author(s):  
Maria Vasconcellos-Dias ◽  
João Marreiros ◽  
Rita Sales ◽  
Vitor Félix ◽  
Paula Brandão ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Catalytic Activity ◽  
Heterogeneous Catalysts ◽  
The Other ◽  
29Si Nmr ◽  
Olefin Epoxidation ◽  
Diimine Ligands ◽  
Imine Nitrogen ◽  
Imine Nitrogen Atom ◽  
Mcm 41

Three new complexes [Mo(η3-C3H5)Br(CO)2{iPrN=C(R)C5H4N}], where R = H (IMP = N-isopropyl 2-iminomethylpyridine), Me, and Ph, were synthesized and characterized, and were fluxional in solution. The most interesting feature was the presence, in the crystal structure of the IMP derivative, of the two main isomers (allyl and carbonyls exo), namely the equatorial isomer with the Br trans to the allyl and the equatorial with the Br trans to one carbonyl, the position trans to the allyl being occupied by the imine nitrogen atom. For the R = Me complex, the less common axial isomer was observed in the crystal. These complexes were immobilized in MCM-41 (MCM), following functionalization of the diimine ligands with Si(OEt)3, in order to study the catalytic activity in olefin epoxidation of similar complexes as homogeneous and heterogeneous catalysts. FTIR, 13C- and 29Si-NMR, elemental analysis, and adsorption isotherms showed that the complexes were covalently bound to the MCM walls. The epoxidation activity was very good in both catalysts for the cis-cyclooctene and cis-hex-3-en-1-ol, but modest for the other substrates tested, and no relevant differences were found between the complexes and the Mo-containing materials as catalysts.

scholarly journals {1-[1-(2-Hydroxyphenyl)ethylidene]-2-(pyridin-2-yl-κN)hydrazine-κ2 N′,O}{1-[1-(2-oxidophenyl)ethylidene]-2-(pyridin-2-yl-κN)hydrazine-κ2 N′,O}nickelate(II) nitrate hemihydrate

2018 ◽  
Vol 74 (5) ◽  
pp. 642-645 ◽  
Author(s):  
Sarr Mamour ◽  
Diop Mayoro ◽  
Thiam Elhadj Ibrahima ◽  
Gaye Mohamed ◽  
Barry Aliou Hamady ◽  
...  
Keyword(s):  
Nitrogen Atom ◽  
Hydrogen Bonds ◽  
Oxygen Atom ◽  
Carbonyl Compounds ◽  
Three Dimensional ◽  
Optical Isomers ◽  
Imine Nitrogen ◽  
Phenolic Oxygen ◽  
Imine Nitrogen Atom ◽  
Nitrate Anions

The 2-hydrazinopyridine precursor has been widely used to prepare ligands of various kinds by condensation with carbonyl compounds. These types of ligands are suitable for synthesizing novel transition metal (II) complexes with interesting magnetic properties. In this context we have synthesized the ligand 1-(2-hydroxyphenyl-2-ethylidene)-2-(pyridin-2-yl)hydrazine (HL) which was used in the preparation of the mononuclear title complex, [Ni(C13H12N3O)(C13H13N3O)]NO3·0.5H2O. As a result of the presence of HL and L in the [{Ni(HL)(L)}]+ unit, the complex appears to be a supramolecular dimer composed of the Δ(−) and Λ(−) optical isomers, which are linked by strong hydrogen-bonds. As well as the dimer generated by two mononuclear [{Ni(HL)(L)}]+ cations, the asymmetric unit also contains two nitrate anions and one water molecule. Each Ni atom is coordinated to two ligand molecules by a nitrogen atom of the pyridine ring, an imine nitrogen atom and a phenolic oxygen atom of one of the ligand molecules and a phenolate oxygen atom of the other organic molecules. The environment around the cation is a distorted octahedron. The basal planes are defined by the two nitrogen atoms of the pyridine rings and the two phenolic oxygen atoms of the ligand, the apical positions being occupied by the azomethine atoms. The O atoms of one of the nitrate ions are disordered over two sets of sites in a 0.745 (9):0.255 (9) ratio. In the crystal, the dimers are linked by numerous hydrogen bonds, forming a three-dimensional framework.

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