Coordination Compounds Of Titanium Research Articles

Novel synthesis, characterization and antimicrobial activities of coordination compounds of Titanium and Zirconium with Schiff base

The titanium(IV) and Zirconium(IV) complexes derived from Schiff base [(Z)-2-(1-(4-((4-methyl-3H-benzo[b][1,4]diazepin-2-yl)oxy)phenyl)ethylidene)hydrazine-1-carboxamide] are reported and characterized based on (Infra-red) IR spectra, 1H NMR spectra, mass spectra. Complexes were found to possess 1:2 (metal:ligand) stoichiometry. The prepared ligands were act as bidentate ligands. The synthesized ligand, in comparison to their titanium(IV) and zirconium(IV) complexes, were screened for antimicrobial activity.

A Titanium(IV) Complex with an OSO-Type Ligand as a Catalyst for the Synthesis of Ultrahigh-Molecular-Weight Polyethylene

Coordination compounds of titanium(IV) with OSO-type ligands have been prepared and characterized, and their catalytic activity in ethylene polymerization has been studied. It has been shown that in the presence of an {Et2AlCl + Bu2Mg} binary cocatalyst, the activity of the titanium-containing catalyst system reaches 1629 kgPE mol(Ti)−1 h−1 and leads to the preparation of ultrahigh-molecular-weight polyethylene (UHMWPE). The UHMWPE reactor powder has been processed by a solvent-free method to high-strength and high-modulus films (σ = 2.32 GPa, E = 125 GPa).

Polymerization of Ethylene in the Presence of Titanium(IV), Zirconium(IV), and Vanadium(V) Coordination Compounds with Salen Ligands

Coordination compounds of titanium(IV), zirconium(IV), and vanadium(V) with chiral salen ligands have been obtained and characterized, and their catalytic activity in the polymerization reaction of ethylene has been studied. It has been shown that in the presence of polymethylaluminoxane as a cocatalyst, the activity of the titanium-containing catalyst system reaches 944 kgPE mol(Ti)−1 h−1 and leads to the preparation of ultrahigh-molecular-weight polyethylene.

Titanium coordination compounds: from discrete metal complexes to metal-organic frameworks.

Owing to their promise in photocatalysis and optoelectronics, titanium based metal-organic frameworks (MOFs) are one of the most appealing classes of MOFs reported to date. Nevertheless, Ti-MOFs are still very scarce because of their challenging synthesis associated with a poor degree of control of their chemistry and crystallization. This review aims at giving an overview of the recent progress in this field focusing on the most relevant existing titanium coordination compounds as well as their promising photoredox properties. Not only Ti-MOFs but also Ti-oxo-clusters will be discussed and particular interest will be dedicated to highlight the different successful synthetic strategies allowing to overcome the still "unpredictable" reactivity of titanium ions, particularly to afford crystalline porous coordination polymers.

Spectroscopic characterization of some new coordination compounds of titanium(IV) with Schiff bases of amino acids

Spectroscopic characterization of some new coordination compounds of titanium(IV) with Schiff bases of amino acids

Coordination compounds of titanium (IV) and 2-hydroxymethyl-phenol derivatives: Their synthesis, structure and catalytic activity in ethylene and 1-hexene polymerization

A series of titanium complexes LTiCl2·(iPrOH)212-18 and heterobimetallic complex L2Ti·iPrOLi·THF 19 bearing saligenin-type [O,O]2- ligands 6-11 were synthesized in high yields from Cl2Ti(OiPr)2 or LiTi(OiPr)5. X-ray structure analyses for 15 and 19 revealed that these complexes adopt a distorted octahedron or distorted tetragonal pyramid geometry. When activated by binary activator {3Et2AlCl + Bu2Mg}, complexes 12-19 exhibited moderate to high activities toward ethylene and 1-hexene polymerization, giving high molecular weight polymers with broad molecular weight distributions. The results of this study show the unique ability of Li and Mg chlorides to improve the catalytic ability of post-metallocene pre-catalysts.

Coordination compounds of titanium and zirconium with 6,6′-(piperazine-1,4-diyl)-bis-(2,4-di-tert-butylphenol) and study of their catalytic activity towards ethylene and 1-hexene polymerizations

Novel titanium and zirconium alkoxo complexes bearing 6,6′-(piperazine-1,4-diyl)-bis-(2,4-di-tert-butylphenolate) ligand (L), LTi2(OiPr)6 (2) and L2Zr2(OBu)4 (3), has been synthesized in acceptable yields by the stoichiometric reaction of L with the respective M(OR)4. All complexes were fully characterized by elemental analysis and NMR spectroscopy, and the molecular structures of the representative complex 2 was confirmed as distorted trigonal bipyramid at titanium (coordination number 5) by single-crystal X-ray diffraction. Pre-catalysts 2–3 are active in ethylene and 1-hexene polymerization in the presence of Et2AlCl/Bu2Mg binary co-catalyst; but there were completely inactive in presence of MAO or Me3Al. Obtained polyethylene and polyhexene samples were of high molecular weight. The results of this study show the unique ability of Mg derivatives to improve the catalytic ability of post-metallocene pre-catalysts.

Titanium (IV) and zirconium (IV) chloride complexes on the base of chiral tetraaryl-1,3-dioxolane-4,5-dimetanol ligands in the polymerization of ethylene: The promoting role of lithium and magnesium chloride

Coordination compounds of titanium (IV) and zirconium (IV) with tetra-aryl-1,3-dioxolan-4,5-dimethanol (1,2) derivatives were synthesized and characterized by NMR- and IR-spectroscopy and X-ray crystallography. It was demonstrated that titanium dichloride complexes (5–6, 9–12) when treated with MAO, TMA or TIBA are inactive in ethylene polymerization catalysis. However, these compounds become catalytically active in presence of lithium or magnesium chlorides. It was found that the magnitude of the resulting catalytic activity correlates with the following factors: mode of non-transition metals chlorides introduction to the reaction mixture, the nature of activator, and its overall amount. Resulting catalytic activity varied between 54 and 3500 kg PE/mole Ti٠h٠bar. Formed polymer was a linear polyethylene of high and ultrahigh molecular weight (over 5.95 105 g/mole) with high polydispersity index. Possible mechanisms of lithium and magnesium chlorides ability to promote the catalytic process were proposed.

Synthesis, Structure, and Ethylene/α-Olefin Polymerization Behavior of (Cyclopentadienyl)(nitroxide)titanium Complexes

Mono-Cp titanium coordination compounds bearing monoanionic ligands derived from stable nitroxyl radicals have been synthesized by two methods: (i) trapping of CpTi(III) species with the stable nitroxyl radical TEMPO (2,2,6,6-tetramethylpiperidine-N-oxyl) to provide Cp‘TiCl2(TEMPO) (Cp‘ = Cp (1) and Cp* (2)) and (ii) salt metathesis of Ti(IV) halides with a nitroxide anion generated by the in situ methylation of tert-butyl-α-phenylnitrone. Alkylation of these complexes with MeLi or MeMgBr furnishes Cp*TiMe2(TEMPO) (3) and Cp‘TiMe2(ON(tBu)(CHMePh)) (Cp‘ = Cp(4) and Cp* (5)). The molecular structure of 2 has been determined by X-ray crystallography to reveal a monoanionic η1-TEMPO ligated to titanium. Complexes 3 and 4 activated with iprAFPB (2,6,-diisopropyl-N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate) efficiently copolymerize ethylene and 1-hexene to provide copolymers having higher 1-hexene contents and higher productivities than the related Cp*Ti(CH2Ph)3 under identical conditions. Comparis...

Vaporization of molecular titanium coordination compounds—a structural–thermochemical approach

A semi-empirical structural–thermochemical approach was employed to study the vaporization properties of new molecular titanium coordination compounds. Examination of intramolecular steric shielding of individual atoms, and analysis of intermolecular close contacts, identified which groups of atoms in the molecules were important. Evaporation enthalpies were calculated by summing the contributions from the individual groups. Addition of the measured melting enthalpies gave sublimation enthalpies agreeing closely with data determined experimentally using high temperature mass spectrometry.

Synthetic and biochemical aspects of titanocene- and zirconocene-dichloride chelates of thiosemicarbazones derived from heterocyclic ketones

This communication deals with a brief description of a synthetic procedure and structural characterization of a new class of coordination compounds of titanium and zirconium with sulphur-containing organic moieties derived by the condensation of heterocyclic ketones and thiosemicarbazide. On the basis of various physicochemical and spectral studies, viz., UV, IR, 1H and 13C NMR, a trigonal bipyramidal and octahedral geometries have been suggested for Cp 2M(Tscz)Cl and Cp 2M(Tscz) 2 (where M = Ti(IV) or Zr(IV) and TsczH = ligand molecule) type of compounds, respectively. Finally, attempts have been made to establish a correlation between biological activity and the structures of the resulting products on the basis of different constituents and chemical phenomenon.

Titanium Coordination Compounds: Classification and Analysis of Crystallographic and Structural Data

Article Titanium Coordination Compounds: Classification and Analysis of Crystallographic and Structural Data was published on July 1, 1986 in the journal Reviews in Inorganic Chemistry (volume 8, issue 3-4).

ChemInform Abstract: Some Coordination Compounds of Titanium and Zirconium Halides with Tertiary Phosphines and Related Ligands.

AbstractThe new ligand Bu2PCH2CH2PBu2 reacts with a toluene solution of the group IVA halides to the adducts (I) with the ligand atoms appearantly in cis positions around a 6‐coordinate metal atom.

Some coordination compounds of titanium and zirconium halides with tertiary phosphines and related ligands

Various new adducts of TiCl 4, (PhO) 2TiCl 2, TiCl 3 and ZrCl 4 with phosphine and amine ligands are reported including, (PhO) 2TiCl 2·2L (or L′) (L = PMe 3, PPh 3; L′ = dmpe, dbpe, tmed); MCl 4·L (M = Ti, Zr; L = dbpe): TiCl 3·L (L = dmpe, dbpe, tmed): TiCl 3·tmed·THF and ZrCl 4·1.5tmed. The solution properties of some of the TiCl 4 adducts are discussed, as deduced from 31P NMR spectra.