Mixed-ligand Chromium Complexes Research Articles

Synthesis and spectral study of mixed ligand complexes of Chromium(III) dibasic tridentate schiff schiff bases as primary and naphthoic acid as co-ligand

The transition metal complexes of Schiff bases have been widely researched on account of their importance as biochemical,analytical and antimicrobial reagent. Herein, the transition metal ion complexes of Cr(III) with dibasic tridentae Schiff bases derived by condensation of thiosemicarbazide with acetoacetanilide as primary ligand and 1-hydroxy-2-naphthoic acid as co-ligand have been prepared. The mixed ligand complexes of the above mentioned metal ion were characterized by analytical, magnetic and electronic spectral study. The transition metal complexes were also evaluated for antifungal activity against Drechslera tetramera, Fusarium-oxysporum and Macrophomia phoseoli at different concentrations.

Solid-Phase Transformations in Tetraamine and Hexaamine Mixed-Ligand Complexes of Chromium(III) with Cyclic Tetraamines

We have studied solid-phase transformations in mixed-ligand complexes of chromium(III) with cyclic tetraamines. We have established that tetraamine complexes of chromium(III) with 14-membered tetraaza macrocyclic ligands are relatively thermally stable, and do not undergo isomerization in the solid state. We have observed that solid-phase reactions of ammonia substitution in hexaamine complexes with outer-sphere iodide and boron hydride anions may be accompanied by dehydrogenation processes.

Synthesis and characterization of some mixed ligand complexes of chromium(III)

Synthesis and characterization of some mixed ligand complexes of chromium(III)

Mixed ligand complexes of chromium(III) and iron(III): synthesis and evaluation as catalysts for oxidation of olefins

The mixed ligand complexes Cr III(dpa)(L)Cl and Fe III(dpa)(L)(H 2O) n Cl (where dpa = dipicolinic acid, l = ethylenediamine, 2,2-bipyridine or 1,10-phenanthroline, n = 1 or 2) were synthesized and characterized by elemental analysis and spectral, magnetic, conductance and electrochemical studies. The complexes were evaluated for their activity as catalysts for the epoxidation of olefins. The chromium complexes catalyzed epoxidation of olefins, viz., norbornene, cis-cyclooctene, styrene and cyclohexene with iodosylbenzene, to give corresponding epoxides. Oxidation of cyclohexene gave allylic oxidation products besides the epoxide. The iron complexes were nearly inactive as epoxidation catalysts under these conditions. Spectrophotometric and electrochemical measurements were used to deduce the cause of low catalytic activity.

Mixed Ligand Complexes of Chromium(III) containing some Bidentate Amines and Quadridentate Schiff Base Ligands

Mixed Ligand Complexes of Chromium(III) containing some Bidentate Amines and Quadridentate Schiff Base Ligands

Mixed-Ligand Complexes of Chromium(III) and Ruthenium(III) Ions with Imides and Amines

Abstract Some novel mixed-ligand complexes of chromium(III) and ruthenium(III) ions with imides and tridentate amines have been prepared and characterized by elemental analyses, conductometric, magnetic, infrared, and electronic spectral studies. The complexes have the general formula [M(im)3.L], where M=Cr(III) or Ru(III); im = anion of succinimide (sim) or phthalimide (pirn); L=diethylenetriamine (det) or 2,2′:6′,2″-terpyridine (tpy). A proposed octahedral structure for the complexes is supported by magnetic and spectral data.

Hydration behavior of mixed ligand chromium complexes. Part I: partial molar volumes and partial molar adiabatic compressibilities of oxalato and mixed oxalato ? Ethylxanthato chromate(III) complexes

Densities and ultrasonic velocities in aqueous solutions of cis-K[Cr(ox)2(H2O)2], K3[Cr(ox)3] and KSSCOC2H5 and a mixed ligand complex K2[Cr(ox)2SSCOC2H5], where SSCOC2H5 is the ethylxanthate ligand, have been measured at 25, 35 and 45°C. Limiting partial molar volumes, partial molar adiabatic compressibilities and hydration numbers of the complex salts as well as of the ligand have been calculated. The implication of the findings are discussed.

Thermal and magnetic studies of mixed ligand complexes of chromium(III) containing dithiocarbamate and acetylacetone/oxine/glycine moieties

Chromium(III) complexes of the type Cr(A)(A′)2, Cr(A)2(A′) and Cr(A)3 have been prepared (whereA is either piperidyldithiocarbamate or morpholyldithiocarbamate andA′ is glycine or oxine or acetylacetone moiety). The mixed ligand complexes have been charac terized by elemental analyses, magnetic susceptibility measurements and thermal studies. The complexes show magnetic moment in the range of 3.5–4.3 B.M. which corresponds to three unpaired electrons. TG studies have also been carried out, in order to study the mode of decomposition of the complexes and to evaluate various kinetic parameters.

Mixed-Ligand Complexes of Cr(III), Fe(III) and Ru(III) Diphenates with Heterocyclic Bases

Abstract Several new mixed ligand complexes of chromium(III), iron(III) and ruthenium(III) with diphenic acid (DAH2) and nitrogen-containing heterocyclic bases have been prepared. The complexes have the compositions K[M(DA)2.L2], K[M(DA)2.L1] and K2[M(DA)2 (OX)], where M = Cr(III), Fe(III) or Ru(III); DA = dianion of diphenic acid; L = quinoline (Q), isoquinoline (IQ), pyridine (Py), 2-picoline (2-Pic) or 4-picoline (4-Pic); L′ = 2-aminopyridine (2-Apy), 3-aminopyridine (3-Apy), 2,2′ -bipyridine (Bipy) or 1, 10-phenan-throline (Phen); OX = anion of 8-hydroxyquinoline. The complexes were characterised on the basis of elemental analyses, conductivity measurements, magnetic measurements, infra-red and electronic spectral studies. All the complexes were found to be octahedral.

Chemistry of the phenylglyoxal-p-diethylaminoanil and/or thiourea substituted ammine complexes

Mixed ligand complexes of chromium(III), cobalt(II), cobalt(III), copper(II) and zinc(II) involving either the phenylglyoxal-p-diethylaminoanil and/or thiourea, and ammonia have been obtained by the partial or complete replacement of the strongly coordinated ammonia of ammine complexes. All the products were characterized by elemental analysis, molar conductance, magnetic susceptibility and i.r. and electronic spectral measurements for their bonding and structures.

Synthesis and physicochemical study of complexes of metals of subgroup VIB with amino alcohols

1. New mixed-ligand complexes of chromium(III) with glycine and mono- and diethanolamines and a number of new complexes of molybdenum(VI) and of tungsten(VI) with ethanolamines and aminopropanols have been obtained; the physicochemical investigation of the complexes obtained by various methods has been made. 2. A structure has been proposed for the coordination sphere of the complexes isolated and the dependence of the composition of the products formed on the nature of the central atom and on the properties of the ligands used have been explained.

The reduction of chromium(V) in non-aqueous media: The preparation of mixed ligand complexes of chromium(III) from [bipyH2][CrOCl5] (bipy = 2,2?-bipyridyl)

The chromium(V) complex [bipyH2][CrOCl5] reacts with MeCN to yield the octahedral chromium(III) complex [CrCl3(bipy)(NCMe)], the nitrile ligand of which can be replaced by other ligands to give [CrCl3(bipy)L] complexes (L = py, pyO, and Ph3PO). However, reactions of [bipyH2]-[CrOCl5] with higher nitriles RCN (R = Et, n-Pr, Ph, or PhCH2) or with MeNO2 all lead to the isolation of [CrCl3(bipy)]n (n most probably being 2), which may also be prepared by thermal decomposition of [CrCl3(bipy)(NCMe)].