cas 546-68-9, Titanium tetraisopropanolate

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Ferroelectric films of Ba0.7-0.8Sr0.2-0.3TiO 3 solid solutions deposited from carboxylate solutions
Ferroelectric films of Ba0.7-0.8Sr0.2-0.3TiO 3 solid solutions 2-3 μm in thickness were deposited onto platinum substrates from carboxylate solutions and characterized by dielectric measurements at 1000 Hz: tC = 15-16°C, ε20 > 1000, tan δ = 0.04-0.06 in the range 10-100°C. The controllability coefficient of the films in a dc electric field between 36 and 42°C is 1.6.
Tomashpol'skii,Golikova,Rybakova
p. 945 - 948
(2002)
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A study on the development of CVD precursors V - Syntheses and characterization of new N-alkoxy-β-ketoiminate complexes of titanium
The synthesis and characterization of various new titanium N-alkoxy-β-ketoiminate complexes are reported. Reactions between N-alkoxy-β-ketoimine ligands and Ti(O- i Pr)4 resulted in dimeric [Ti(O- i Pr)2 (N-alkoxy-β-ketoiminate)]2 complexes or monomeric [Ti(N-alkoxy-β-ketoiminate)2] ones depending on the amount of ligands. Terdentate N-alkoxy-β-ketoiminate ligands do not prevent dimer complexes from undergoing disproportional rearrangement to produce Ti(O- i Pr)4 and [Ti(N-alkoxy-β-ketoiminate)2]. The mechanism of this behavior is too complicated but it may include the dissociation and recoordination of ligands. Crystal structures of [Ti(N-alkoxy-β-ketoiminate)2] (MeC(O)CHC(Me)NC(Et)CH2O (3f) and t-BuC(O)CHC(Me)NCH2CH(Me)O (3k)) show that these are distorted octahedron and β-ketoiminate ligands appear to coordinate as a β-imino enolate. Two terdentate β-ketoiminate ligands coordinate meridionally and they are perpendicular to each other. Thermal characteristics of monomeric and dimeric titanium complexes were determined by TGA and DSC and these are reasonably volatile as potential precursors of TiO2 thin films.
Lim, Sunkwon,Choi, Bohyun,Min, Yo-Sep,Kim, Daesig,Yoon, Il,Lee, Shim Sung,Lee, Ik-Mo
p. 224 - 237
(2004)
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Synthesis, crystal structures and spectroscopic characterization of [Ti8O8(OOCR)16] (where R = But, CH2But, C(CH3)2Et)
Multinuclear titanium(IV) oxo carboxylates of the general formula [Ti 8O8(OOCR)16] (where R = But (1), CH2But (2), C(CH3)2Et (3)) have been synthesized in a reaction of titanium isopropoxide with the appropriate organic acids in a molar ratio of 1:2. The composition and structure of these compounds were identified by elemental analysis, IR, NMR and X-ray single-crystal diffraction. The crystal structure of 1 was solved in the orthorhombic space group Pbca. Titanium atoms form oligomeric [Ti8(μ2-O) 8] rings, where each Ti cation is surrounded by six oxygen atoms (two μ2-oxo and four μ-carboxylato bridges). Within the ring the Ti-Ti distances between neighboring titanium ions range from 3.333(1) to 3.366(1) A? and the mean value of the Ti-Ti-Ti angle is 134.2(1.3)°. Results of IR, NMR and MS studies proved that in the structures of 2 and 3, multinuclear [Ti8(μ2-O)8] clusters stabilized by carboxylate bridges are also formed. TGA/DTG, MS and variable temperature IR + (VT-IR) studies have been carried out in order to determine the thermal stability and thermal decomposition mechanism of the Ti(IV) carboxylates mentioned above.
Piszczek,Richert,Grodzicki,G?owiak,Wojtczak
p. 663 - 670
(2005)
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Ferroelectric lead zirconate titanate films prepared by spray pyrolysis of carboxylate solutions
Ferroelectric PbTi0.6Zr0.4O3films 0.5-1.5 μm in thickness were produced on platinum substrates by spray pyrolysis of carboxylate solutions. The optimized compositions of the precursor solutions, containing methacrylic acid
Tomashpol'skii,Rybakova,Lunina,Fedoseeva,Prutchenko,Men'shikh
p. 500 - 507
(2001)
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Preparation method of titanium tetraisopropoxide
The invention relates to a preparation method of titanium tetraisopropoxide. The preparation method comprises the following steps: mixing a solvent, titanium tetrachloride and isopropanol to prepare amixed reaction system; and adding dialkylamine into the mixed reaction system to react, and carrying out aftertreatment on the obtained reactant to prepare the titanium tetraisopropoxide. The preparation method comprises the following steps: taking titanium tetrachloride and isopropanol as raw materials and adding dialkylamine into the mixed reaction system, wherein the dialkylamine can effectively absorb HCl generated by the reaction of the mixed reaction system, the reaction is promoted, meanwhile, impurities can be prevented from being generated, the high-purity titanium tetraisopropoxidecan be prepared through simple post-treatment, and the yield is high.
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Paragraph 0047-0088

(2020/11/26)

TRIDENTATE NITROGEN BASED LIGANDS FOR OLEFIN POLYMERISATION CATALYSTS
Catalyst systems and methods for making and using the same are provided. A method for forming a polymer catalyst includes reacting a bromoketone compound with an aryl amine compound to form an amide compound. The amide compound is reacted with an ethylene diamine compound, to form a terminal primary amine compound. The terminal primary amine compound is reacted with a bromoaryl compound to form a ligand.
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(2016/02/16)

Dithiocarbamate complexes of Ti(IV) alkoxides: Synthesis, characterization, and electrochemistry
Isopropoxy- and ferf-butoxy-fr;'s(dithiocarbamato)titanium(IV) complexes of five dithiocarbamate ligands were prepared and characterized by LDI-MS, 1H NMR, 13C NMR, and elemental analysis, as well as by crystallographic determination of two examples. Both
Donzelli, Alberto,Potvin, Pierre G.
p. 4171 - 4178
(2009/09/26)

Use of an organometallic compound to protect and/or strengthen a keratin material, and treatment process
The use of a composition comprising at least one organometallic compound which may be obtained by partial or total hydrolysis, and partial or total condensation, of at least one metallic precursor, to at least one of protect and strengthen a keratin material.
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(2008/06/13)

Asymmetric synthesis of anti-homopropargylic alcohols from aldehydes and chiral sulfonimidoyl substituted bis(allyl)titanium complexes through generation and elimination of novel chiral alkylidenecarbene (dimethylamino)sulfoxonium ylides
A new method for the asymmetric synthesis of anti-configured homopropargylic alcohols 1 is described, which features the addition of chiral sulfonimidoyl substituted bis(allyl)titanium complexes 3 to aldehydes, the methylation of sulfonimidoyl substituted homoallylic alcohols 2 at the N-atom, and the elimination of alkenyl (dimethylamino)sulfoxonium salts 7 with LiN(H)tBu. The reaction of isopropyl, cyclohexyl, and methyl substituted allylic titanium complexes 3a-c with benzaldehyde, p-bromobenzal-dehyde, p-chlorobenzaldehyde, p-methoxybenzaldehyde, (E)-3-phenylpropenal, and phenylpropynal afforded with high regio- and diastereoselectivities the anti-configured sulfonimidoyl substituted homoallylic alcohols 2a-j, respectively. Only one allylic unit of the titanium complexes 3a-c was transferred in the case of unsaturated aldehydes, and the starting allylic sulfoximines 2a-g were recovered in approximately 50% yield. The methylation of the silyl protected alkenyl sulfoximines 6a-j with Me3OBF4 gave in practically quantitative yields the (dimethylamino)sulfoxonium salts 7a-j, respectively. Salts 7a-e, 7g, 7h, and 7j delivered upon treatment with 2 equiv of LiN(H)tBu the enantio- and diastereomerically pure saturated and unsaturated alkynes 9a-e, 9g, 9h, and 9j, respectively, in high yields. Besides the alkynes the sulfinamide 8 (96% ee) was isolated. Aminosulfoxonium salts 9f and 9i, which carry a CC triple bond, also suffered an elimination under these conditions but did not yield the corresponding diynes. Elimination of salts 7a-e, 7g, 7h, and 7j proceeds most likely through deprotonation at the α-position with formation of the novel alkylidenecarbene aminosulfoxonium ylides 19a-e, 19g, 19h, and 19j, respectively. The ylides 19a-e, 19g, 19h, and 19j presumably eliminate sulfinamide 8 with generation of the chiral nonracemic β-siloxyalkylidene)carbenes 20a-e, 20g, 20h, and 20j, which suffer a 1,2-H-shift with formation of alkynes 9. Support for the formation of the putative alkylidenecarbenes 20 as intermediates comes from the elimination of the β-methyl substituted aminosulfoxonium salt 24, which delivered the enantio- and diastereomerically pure 2,3-dihydrofuran derivative 28 upon treatment with LiN(H)tBu in high yield. Here, the putative β-siloxyalkylidene)carbene 26 suffers a 1,5-O,Si bond insertion rather than a 1,2-Me shift. Methylation of the alkenyl sulfoximine 6a at the α-position with formation of 13 was achieved through deprotonation of the former with formation of the α-lithioalkenyl sulfoximine 11a and its treatment Mel. Reaction of the α-methylated alkenyl aminosulfoxonium salt 14a with LiN/Pr2 at low temperatures gave the enantio- and diastereomerically pure anti-configured homoallenylic alcohol derivative 15, while reaction of the salt with LiN/Pr2 or LiN(H)tBu at higher temperatures afforded the enantio- and diastereomerically pure nonterminal homopropargylic alcohol derivative 17. Deprotonation of the alkenyl (dimethylamino)sulfoxonium salts 7a and 7b with nBuLi afforded the novel alkylidenecarbene aminosulfoxonium ylides 19a and 19b, respectively, which upon treatment with Mel yielded the methylated aminosulfoxonium salts 14a and 14b, respectively.
Reddy, Leleti Rajender,Gais, Hans-Joachim,Woo, Chang-Wan,Raabe, Gerhard
p. 10427 - 10434
(2007/10/03)

Purified alkoxide and process for purifying crude alkoxide
A purified alkoxide from which volatile impurities causing polymerization and degradation of the alkoxide are removed to extremely low concentrations. The purified alkoxide can be obtained by distilling a crude alkoxide and stripping the distilled liquid alkoxide by applying ultrasonic vibration while passing an inert gas through the liquid alkoxide. A high quality thin insulating film excellent in flatness with few defects such as voids can be obtained by using the purified alkoxide of the present invention as a CVD material.
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(2008/06/13)

Heterogeneous epoxidation catalyst
Highly active and selective epoxidation catalysts are prepared by combining high surface area silica support or the like, having surface area greater than 1100 m2/g, with a titanium source. The titanium source is a non-oxygenated hydrocarbon solution of a titanium halide or a vapor stream of titanium tetrachloride. The impregnated support it then calcined at an elevated temperature (preferably, in a substantially oxygen-free atmosphere), and, optionally, reacted with water and/or silylated. The resulting materials are highly active heterogeneous epoxidation catalysts for the reaction of olefins to with organic hydroperoxides.
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(2008/06/13)

Azolobenzazepine derivatives as neurologically active agents
PCT No. PCT/GB97/00592 Sec. 371 Date Sep. 3, 1998 Sec. 102(e) Date Sep. 3, 1998 PCT Filed Mar. 4, 1997 PCT Pub. No. WO97/32883 PCT Pub. Date Sep. 12, 1997The invention relates to azolobenzazepine derivatives of formula (I), wherein: X is O or S; R1, R2, R3 and R4 are independently hydrogen, perfluorolower-alkyl, halogen, nitro or cyano; and C together with the carbon atoms to which it is attached forms a 5-membered aromatic heterocycle selected from the group consisting of a pyrazol and triazole, to pharmaceutical compositions containing them and to methods for the treatment of neurological disorders utilizing them.
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(2008/06/13)

Di-tert-butyl Phosphate Complexes of Titanium
Reactions of 1 equiv of HO(O)P(O1Bu)2 with Ti(OR)4 (R = Et, 1Pr) give the new molecular titanium phosphates [Ti(OR)3O2P(O1Bu)2]n (1, R = Et; 2, R = 1Pr). In the solid state, 2 exists as a centrosymmetric dimer containing five-coordinate metal centers. Addition of 2 equiv of KOEt to an ethanol solution of 1 led to the formation of [Ti2K(OEt)8O2P(O1Bu} 2]2 (3) and 1 equiv of KO2P(O1Bu)2. A single-crystal X-ray structure analysis of 3 revealed that this complex exists in the solid state as a centrosymmetric dimer containing two Ti-centered. face-sharing pseudooctahedra in the unique half of the dimer. Addition of 2 equiv of KO1Pr to a 2-propanol solution of 2 led to the formation of KO2P(O1Bu)2 (4) and Ti(OiPr)4 in high yield. Cooling a 2-propanol solution of 4 to -80 °C led to crystallization of the solvated tetramer [4·HOiPr3]4 (mp = -30 °C). A single-crystal X-ray structure analysis revealed that this tetramer possesses a cuhelike K4O4 core with 4-fold improper rotation symmetry. Multinuclear NMR studies of 1-3 show that the structures of these complexes are dynamic in solution. Crystals of 4 are tetragonal (P42/n) with a= 18.6261(3) A, c = 14.7114(3) A, and Z = 8.
Lugmair, Claus G.,Don Tilley
p. 1821 - 1826
(2008/10/08)

Process for preparing pyrrolidinones
A process for the preparation of a compound of general formula II: STR1 wherein R1 is hydrogen, or C1 -C10 hydrocarbyl or heterocyclyl having 3 to 8 ring atoms, either of which may optionally be substituted; each R2, R3, R4 and R5 is independently hydrogen or C1 -C4 alkyl; A is an optionally substituted aromatic or heteroaromatic ring system; and R21 is hydrogen, halogen, OH or OCONHR1, wherein R1 is as defined above; the process comprising cyclizing a compound of general formula III: STR2 wherein A, R2, R3, R4, R5 and R21 are as defined in general formula II and R25 is a leaving group such as a halogen atom; under basic conditions.
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(2008/06/13)

HYDROXAMIC ACID AND CARBOXYLIC ACID DERIVATIVES, PROCESS FOR THEIR PREPARATION AND USE THEREOF
This disclosure relates to a novel class of hydroxamic and carboxylic acid based matrix metalloproteinase inhibitor derivatives. The disclosure further relates to pharmaceutical compositions containing such compounds and to the use of such compounds and compositions in the treatment of matrix metalloproteinase induced diseases.
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(2008/06/13)

An NMR study of mixed, tartrate-containing TiIV complexes
The reactions of amines and amino alcohols with diisopropyl or diethyl R,R- or S,S-tartrate and Ti(OiPR)4 were examined by 1H and 13C NMR to obtain and characterize nonfluxional complexes with the tartrate units in novel binding modes.The mildly acidic 8-hydroxyquinoline and N-phenyl-N-benzoylhydroxylamine selectively formed the products of a double OiPr substitution, Ti2(tartrate)2(ligand)2(OiPr)2, and the products of double tartrate substitution, Ti(ligand)2(OiPr)2, while 2,4-pentanedione formed only the latter.Basic amino alkanols formed diastereomerically pure Ti2(tartrate)2(aminoalkoxide)(OiPr)3 species.N,N-Dimethyl-2-aminoethanol (Hdmae) also and uniquely formed monomeric Ti(tartrate)2(Hdmae)2 species that could be described as doubly zwitterionic.Secondary or tertiary amines formed triply C2-symmetric Ti3(tartrate)4(amine)2(OiPr)4 assemblies.Some minor components were belived to be μ-OiPr species.All mixed complexes except Ti(tartrate)2(Hdmae)2 contained chelating and bridging tartrate units, without coordination by ester carbonyls.A nonchelating, nonbridging tartrate unit was also present in the amino alcohol cases.Primary amines, aromatic amines, and hydrazines all failed to provide identifiable complexes.As well, N,N-dibenzylhydroxylamine failed to generate in solution the complex that had previously been characterized by X-ray crystallography.Amidst the rich chemistry of TiIV-tartrate systems, the evident selectivities in product formation were described to macro-ring closures that are specifically directed by the electronic nature of the addend.Transient OiPr-bridged intermediates were also implicated.Key words: mixed TiIV alkoxides, chiral TiIV alkoxides, enantiospecific complexation.
Potvin, Pierre G.,Fieldhouse, Benjamin G.
p. 401 - 413
(2007/10/03)

Mechanism of asymmetric epoxidation. 2. Catalyst structure
The dominant species in equimolar mixtures of titanium tetraalkoxides and dialkyl tartrate esters is shown to be [Ti(tartrate)(OR)2]2, which is identified as the active catalyst for asymmetric epoxidation of allylic alcohols by tertiary alkyl hydroperoxides. The solution-phase structure of this species is consistent with the results of an X-ray structural determination of a titanium tartramide complex reported previously, as analyzed by IR and 1H, 13C, and 17O NMR spectrometry. The first 17O NMR spectra of titanium(IV) alkoxide and alkyl peroxide complexes are reported, as well as the results of a secondary deuterium isotope effect study on the asymmetric epoxidation reaction. General conclusions concerning the mechanism of asymmetric epoxidation are presented.
Finn,Sharpless, K. Barry
p. 113 - 126
(2007/10/02)

Mechanism of asymmetric epoxidation. 1. Kinetics
The rate of titanium-tartrate-catalyzed asymmetric epoxidation of allylic alcohols is shown to be first order in substrate and oxidant, and inverse second order in inhibitor alcohol, under pseudo-first-order conditions in catalyst. The rate is slowed by substitution of electron-withdrawing substituents on the olefin and varies slightly with solvent, CH2Cl2 being the solvent of choice. Asymmetric induction suffers when the size of the alkyl hydroperoxide is reduced. Kinetic resolution of secondary allylic alcohols is shown to be sensitive to the size of the tartrate ester group and insensitive to the steric nature of inhibitor alcohol. Most importantly, the species containing equimolar amounts of Ti and tartrate is shown to be the most active catalyst in the reaction mixture, mediating reaction at much faster rates than titanium tetraalkoxide alone.
Woodard, Scott S.,Finn,Sharpless, K. Barry
p. 106 - 113
(2007/10/02)

SYNTHESIS OF ALKYL ORTHOTITANATES IN TWO-PHASE SYSTEMS.
The authors have carried out an investigation aimed at development of more convenient methods for production of alkyl orthotitanates in two-phase systems. In studies of the reaction of titanium tetrachloride with alcohols in presence of organic amides the authors found that the latter are not indifferent solvents but take part in the reaction. The interaction of titanium tetrachloride, an organic amide, and an alcohol in 1:4:(8-9. 6) molar ratio results in splitting of the amide and formation of the corresponding amine hydrochloride and ester.
Yatluk,Suvorov
p. 1678 - 1680
(2008/10/08)