Search results for "OCTA"
showing 10 items of 1862 documents
Synthesis, crystal structure and magnetic properties of the chiral iron(II) chain [Fe(bpym)(NCS)2]n (bpym = 2,2′-bipyrimidine)
1996
Abstract The iron(II) compound of formula [Fe(bpym)(NCS)2]n (bpym = 2,2′-bipyrimidine) has been synthesized and its crystal structure determined by X-ray diffraction methods. It crystallizes in the tetragonal P41 (No. 76) and P43 space groups, a = 8.849(2), c=16.486(3) A , V=1290.9(5) A 3 , Z=4, D c =1.699 g cm −3 , M r =330.2, F(000)=664, λ( Mo K α)=0.71073 A , μ( Mo K α)=14.8 cm −1 and T=295 K. A total of 2449 reflections was collected over the range 3≤2ϑ≤55°; of these, 1657 were unique and 1321 were considered as observed (13σ(I)) and used in the structural analysis. The final R and Rw residuals were 0.027 and 0.026, respectively. The structure is made up of chiral (Δ and Λ enantiomers c…
Organotin(IV) chloride complexes with phosphocholine and dimyristoyl-L-?-phosphatidylcholine
2000
Several complexes of R n SnCl 4-n (R = Me, Ph, n = 1-3; R = nBu, n = 2, 3) with phosphocholine and dimyristoyl-L-α-phosphatidylcholine (phospholipid) have been synthesized and characterized by means of Mossbauer spectroscopy and NMR. Triorganotin chlorides form complexes of (R 3 SnCl) 2 .L stoichiometry with a trigonal bipyramidal pentacoordinate tin environment, while the others form 1:1 complexes with an octahedral hexacoordinate tin environment, with the ligands coordinating through anionic phosphodiester moieties in all cases.
Self-Assembly of the Hexabromorhenate(IV) Anion with Protonated Benzotriazoles: X-ray Structure and Magnetic Properties
2014
Two novel ReIV compounds of formulas [HBTA]2[ReIVBr6] (1) and [HMEBTA]2[ReIVBr6] (2) [BTA = 1H-benzotriazole and MEBTA = 1-(methoxymethyl)-1H-benzotriazole] have been synthesized and magneto-structurally characterized. 1 and 2 crystallize in the triclinic system with space group P1̅. In both compounds, the rhenium ion is six-coordinate, bonded to six bromo ligands in a regular octahedral geometry. Short ReIV–Br···Br–ReIV contacts, π–π stacking, and H-bonding interactions occur in the crystal lattice of both 1 and 2, generating novel supramolecular structures based on the ReIV. The different dispositions of the cations and the intermolecular Br···Br contacts in 1 and 2 play an important stru…
Synthesis, structural analysis, and thermal and spectroscopic studies of methylmalonate-containing zinc(II) complexes
2012
The synthesis, crystal structure, thermal analysis and spectroscopic studies of five zinc(II) complexes of formulae [Zn(Memal)(H2O)]n (1) and [Zn2(L)(Memal)2(H2O)2]n (2-5) [H2Memal = methylmalonic acid, and L = 4,4′-bipyridine (4,4′-bpy) (2), 1,2-bis(4-pyridyl)ethylene (bpe) (3), 1,2-bis(4-pyridyl)ethane (bpa) (4) and 4,4′-azobispyridine (azpy) (5)] are presented here. The crystal structure of 1 is a three-dimensional arrangement of zinc(II) cations interconnected by methylmalonate groups adopting the μ3-κ2O:κO’:κO”:κO”’ coordination mode to afford a rare (10,3)-d utp-network. The structures of the compounds 2-5 are also three-dimensional and they consist of corrugated square layers of meth…
Tin(IV) complexes with O-ethyl(N-ethyl-N,N-dimethylammoniomethyl)phosphonate
1999
Abstract O,O-Diethyl-(N,N-dimethylaminomethyl)phosphonate undergoes ethyl migration leading to O-ethyl-(N-ethyl-N,N-dimethylammoniomethyl)phosphonate (L). Several new complexes of tin(IV) and organotin(IV) chlorides with the title ligand have been synthesized. The stoichiometry of the obtained complexes is as follows: (R3SnCl)2 · L (R=Me, Bu, Ph), R2SnCl2 · L (R=Me, Bu, Ph), RSnCl3 L (R=Me, Ph) and SnCl4 · L. All the complexes have been studied in solution by means of 1H-, 13C-, 31P- and 119Sn-NMR spectroscopy. Their solid state structures have been investigated by means of Mossbauer spectroscopy and the molecular structure of the complex (Ph3SnCl)2 · L has been determined by X-ray crystall…
A Combined Experimental and Theoretical Study on Bis(μ‐alkoxo)diiron(III) Complexes with Hydroxybenzylaminoethanol [O,N,O] Donor Ligands: Syntheses, …
2011
Three new neutral bis(μ-alkoxo)diiron(III) complexes were prepared from N(R),N-(2-methylene-4,6-di-tert-butylphenol)aminoethan-1-ol ligands (H2L1, R = Me and H2L2, R = H). In these complexes, the ligand wraps around the metal center exhibiting a tridentate facial coordination mode with alkoxo-bridging oxygen, amine nitrogen and phenoxo oxygen donor atoms. In the complex [Fe(acac)L1]2·MeCN (1) acetylacetonato coligand complete the distorted octahedral coordination spheres of the iron(III) ions, whereas in the five-coordinate iron(III) chloride complexes [FeClL1]2 (2) and [FeClL2]2 (3) the ligands induce a geometry that is intermediate between square pyramidal and trigonal bipyramidal. Magnet…
Synthesis, crystal structure and magnetic properties of a new [ZnII6DyIII6] dodecanuclear motif
2013
Abstract A new dodecanuclear complex, [{(HL)(L)(dmf)ZnIIDyIII(dmf)(H2O)}6]·3dmf·4.2H2O has been assembled using a supramolecular compartmental ligand (H3L results from the condensation reaction of 3-formylsalicylic acid and hydroxylamine). The six DyIII ions describe an octahedron that is inscribed into the octahedron generated by the zinc(II) ions each DyIII ion from this motif behaving as a single ion magnet.
Crystal structure and mössbauer spectroscopy studies of the ferrimagnetic complex bimetallic salt hexaamminechromium (III) hexachloroferrate (III), […
1992
The crystal and molecular structures of the ferrimagnetic bimetallic complex salt hexaamminechromium(III) hexachloroferrate(III), [Cr(NH3)6][FeCl6], have been determined from single-crystal, three-dimensional x-ray diffraction counter data. The compound crystallizes as orange coloured crystals in the space groupC2/c of the monoclinic system with Z=4 and has cell dimensionsa=11.325(1) A,b=11.387(1) A,c=11.233(1) A, and β=90.83(1)A. The structure was refined by using segmented block diagonal least-squares techniques to discrepancy indices R and Rw of 0.0233 and 0.0285, respectively. The metal ions occupy sites with symmetry $$\bar 1$$ and are nearly octahedrally coordinated. In the [FeCl6]3− …
Organoelement derivatives of steroids: synthesis and structural characterization of diorganotin chloride adducts of hormones
1986
Abstract Ten new diorganotin dichloride adducts of hormones of the type R 2 SnCl 2 ·2L [where R = Me, Et, n-Bu, Oct and Ph; L = 4-androsten-17s-ol-3-one ( A ); 5-androsten-3s-ol-17-one ( B ); 4-androsten-17α- methyl-17s-ol-3-one ( C ) and 3,17-dihydroxy-5- pregnene-20-one ( D )] have been prepared and characterized at 297 K and 223 K. Spectroscopic measurements (IR; Raman; 1 H, 13 C, 119 Sn NMR) suggest the dissociation or fast ligand exchange in solution at 297 K. Hexa-coordinated adducts with bonding through carbonyl oxygen and trans -R groups in octahedral geometry are formulated at 223 K.
One-dimensional oxalato-bridged copper(II) complexes with 3-hydroxypyridine and 2-amino-4-methylpyridine
2001
Two new one-dimensional oxalato-bridged copper(II) compounds of formula [Cu(ox)L2]n (1) and {[Cu2(ox)2L%3]·L%}n (2) [ox oxalate dianion, L3-hydroxypyridine (pyOH) and L% 2-amino-4-methylpyridine (ampy)] have been synthesized and characterized by FT-IR spectroscopy, variable-temperature magnetic measurements and single-crystal X-ray diffraction. The crystal structure of 1 comprises chains of copper atoms in which cis-[Cu(pyOH)2] 2 units are sequentially bridged by asymmetric bis-bidentate oxalato ligands with an intrachain copper‐copper separation of 5.548(1) A, . Each copper atom is six-coordinated: four oxygen atoms belonging to two bridging oxalato ligands and two nitrogen atoms from two …