Convenient and High-Yielding Preparations of Mono(5-carboxy-2-ethylpentyl) Phthalate and its Ring-Deuterated Isomer – The “Third” Major Metabolite of Bis(2-ethylhexyl) Phthalate

The synthesis of an oxidative major metabolite of bis(2-ethylhexyl) phthalate is described. The target molecule and its ring-deuterated isomer were obtained via acylation of the appropriate -hydroxy benzyl ester or the corresponding carboxylate with phthalic anhydride or phthalic anhydride-d₄. All transformation steps proceed with high yields.     

Isolation of 2-Chloro-5-methylpyridine from its Isomer 2-Chloro-3-methylpyridine by Formation of its Copper(II) Complex

2-Chloro-5-methylpyridine is an important intermediate for the preparation of biological active compounds, especially insecticides1, e.g. imidacloprid2, and is usually manufac- tured from 3-methylpyridine N-oxide. However, the manufacturing process also forms the by-products: 3-methylpyridine and its isomer 2-chloro-3-methylpyridine3. The pro- perties of the isomers are similar, it is difficult to separate by ordinary methods, such as distillation. Scheme 1 79.4%13.6%5.2%NClCH3NCH3ClNC…     

Reactions of Magnesium and Tin with Bis(η5-Cyclopentadienyltricarbonylmolybdenum)indium and -bismuth Chlorides

Oxidation of magnesium and tin with bis(⁵-cyclopentadienyltricarbonylmolybdenum)indium and -bismuth chlorides in polar solvents yielded no organic heteropolymetallic complexes; instead, metallic indium and bismuth were isolated from the reaction mixture.     

One-step in-syringe dispersive liquid–liquid microextraction and GC-FID determination of trace amounts of di(2-ethylhexyl) phthalate and its metabolite in human urine samples

Di(2-ethylhexyl) phthalate (DEHP) is used as plasticizer in polyvinylchloride (PVC) plastics. Its metabolites and the parent phthalates are considered toxic. As the DEHP plasticizers are not chemically bound to PVC, they can migrate, evaporate or be leached into indoor air and atmosphere, foodstuff, and other materials. We have reported a novel, easy and available analytical method for the determination of DEHP and its metabolite, mono(2-ethylhexyl) phthalate (MEHP) in human urine samples by the in-syringe dispersive liquid–liquid microextraction method coupled with gas chromatography with flame ionization detector. The limits of detection and precision (RSD) were 2.5 μg/L and 1.4% for DEHP and 1.1 μg/L and 3.0% for MEHP, respectively. This method could be utilized for routine monitoring of the trace DEHP and MEHP in urine of human exposure to plasticizers.     

Synthesis and characterization of a 2, 5-Bis(trimethylsilyl)-substituted Bis(1, 1′-silolide) dianion

A novel silyl-substituted bis(1, 1′-silolide) dianion has been isolated and characterized by single-crystal X-ray analysis for the first time. The ¹H, ²⁹Si, and ¹³C NMR spectra show significant delocalization of the negative charges to the silole ring. X-ray crystallography revealed equalized C?C distances and DFT calculation also indicates for significant aromaticity. Reaction with trimethylchlorosilane gave the expected bis(1, 2, 5-tris(trimethylsilyl)-3, 4-diphenyl-silacyclopentadienyl).     

A One-dimensional Coordination Polymer of Copper(Ⅱ) and Bis(4,6-dimethyl-2-pyrimidinethiolato)methane

Reaction of bis(4,6-dimethyl-2-pyrimidinethiolato)methane(bpytm) with CuCl2·4H2O in a mixed methanol/dichloromethane solution gave a one-dimensional coordina-tion polymer [CuCl2(μ-bpytm)]n which was characterized by single-crystal X-ray diffraction.It crystallizes in monoclinic,space group P21/c with a=16.9433(5),b=13.6986(4),c=7.8434(2),β=100.371(2)°,V=1790.71(9)3,Z=4,Mr=426.86,Dc=1.583 g/cm3,μ(MoKα)=1.751mm-1,F(000)=868,S=1.025,the final R=0.0399 and wR=0.0924 for 2538 observed reflections with Ⅰ2σ(Ⅰ) and 206 variables.The neutral coordination polymer is constructed by the bidentate thioether ligands to link adjacent copper atoms.Each copper atom is bridged by two adjacent nitrogen atoms of bpytm ligands and terminally bonded by two chloride atoms to form a squareplanar coordination geometry.The average Cu-N and Cu-Cl bond lengths are 2.025(2) and 2.234(1),respectively.     

Synthesis and Structure of Bis[2,6-bis(2-pyridylamino)pyridinium] Tetrachlorocadmiumate(II)

1 INTRODUTION The d10 configuration of Cd(II) permits a wide variety of coordination numbers and geometries[1~3]. In recent years, one-, two- and three-dimensional infinite supramolecular coordination assemblies of Cd(II) have been the subject of great interest owing to their potential applications in catalysis, optical properties, clathration, etc[4~8]. In fabricating the coordination assemblies, organic ligands as well as inorganic anions have been observed to control the structural di…     

Application of the Ion Pair of 2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol and Ammonium Tetraphenylborate for Preconcentration of Trace Vanadium and Determination by Third Derivative Spectrophotometry

ＩｎｔｒｏｄｕｃｔｉｏｎＶａｎａｄｉｕｍｉｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｅｌｅｍｅｎｔｗｈｉｃｈａｆｆｅｃｔｓｔｈｅｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｓｔｅｅｌ,ａｌｌｏｙｓａｎｄｈｉｇｈｐｕｒｉｔｙｍｅｔａｌｓ .Ｉｔｉｓｗｉｄｅｌｙｄｉｓｔｒｉｂｕｔｅｄｉｎｔｈｅｅａｒｔｈ’ｓｃｒｕｓｔ,ａｎｄｉｔｓｃｏｍｐｏｕｎｄｓｃａｎｂｅｈｉｇｈｌｙｔｏｘｉｃｔｏｍａｎａｎｄａｎｉｍａｌｓａｎｄｃａｕｓｅｅｎｖｉｒｏｎｍｅｎｔａｌｄｉｓｅａｓｅｓｗｈｅｎｒｅｌｅａｓｅｄｉｎｔｈｅａｔｍ…     

The formation and properties of mono-cyclopentadienyltitanium dichloride complexes containing trimethylphosphine and isonitrile ligands: molecular structure of (η5-C5H5)TiCl2(PMe3)2

Reduction of CpTiCl₃ in THF solution by magnesium in the presence of either excess trimethylphosphine or 2,6-dimethylphenylisonitrile at ca. −30°C produces the titanium(III) complexes CpTiCl₂(PMe₃)₂ and CpTiCl₂(CNC₆H₃Me₂)₂, respectively, in good yields. The X-ray structure of CpTiCl₂(PMe₃)₂ is reported.     

The resonance Rayleigh scattering of the interaction of copper(Ⅱ)-bleomycinA2 with DNA and its analytical application

The forming of bleomycinA2-Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence spectra.The result shows that in aqueous solution,bleomycinA2(BLMA2) can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of BLMA2.When the cationic chelate further bound with DNA to form ternary ion-association complexes,the r...     

Synthesis of l-(5-Nitro-2-Pyridylazo)-2.7-Dihydroxy-naphthalene and its Color Reaction with Cobalt (Ⅱ)

Pytrdylazo reagent is an important chromogenic reagent. PAN is typical one. The new reagent, l-(5-nitro-2-Pyridylazo)-2.7-dihydroxy-naphthalene (5-NO₂-PADN) has been synthesized by to take up -OH and -NO₂ groups at the PAN, and it was confirmed with IR and elements analysis.     

Syntheses and Anti-inflammatory Action of (η-C_5H_5)_2Ti(Cin)_2 and (η-C_5H_5)_2Ti(Tzea)_2

ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｎｃｅＫ ｐｆｄｉｓｃｏｖｅｒｅｄｔｈａｔｄｉｃｙｃｌｏｐｅｎｔａｄｉ ｅｎｙｌｔｉｔａｎｉｕｍｄｉｃｈｌｏｒｉｄｅｅｘｈｉｂｉｔｅｄａｎｔｉｔｕｍｏｕｒａｃｔｉｏｎｉｎ1979,1ａｌａｒｇｅｎｕｍｂｅｒｏｆｃｙｃｌｏｐｅｎｔａｄｉｅｎｙｌｔｉｔａｎｉｕｍｃｏｍ ｐｌｅｘｅｓｂｅａｒｉｎｇｄｉｆｆｅｒｅｎｔｓｕｂｓｔｉｔｕｅｎｔｓｈａｖｅｂｅｅｎｓｙｎｔｈｅ ｓｉｚｅｄ .2 ,3Ｔｈｅｅｘｐｅｒｉｍｅｎｔａｌｄａｔａｒｅｖｅａｌｅｄｔｈａｔ (Ｃｐ) 2 ＴｉＸ2(Ｘ =ｈａｌｏｇｅｎ ,ｐ…     

Characterization and Crystal Structure of Bis(N'-ethyl-N-piperazinly-carbodithioato-S,S') Nickel(II) Complex:Ni(S_2CNC_4H_8NC_2H_5)_2

1 INTRODUCTION The ability of dialkyldithiocarbamate anion, -S2- CNR2 (dtc) ligand, to bind metal has been known for many years[1, 2]. It forms a chelate with virtually all transition elements and is proven to be a versatile chelating agent for the separation and extract of metals in analytical chemistry and mineral floa- ting[3～5]. Water soluble dialkyldithiocarbamate com- plexes have been tested in various medical appli- cations[6]. Some of substituted dithiocarbamate salts also show …     

Methyl 2-[(tert-Butoxycarbonyl)amino]-3-hydroxy-3-phenylpropanoate: Synthesis of Erythro (±) Isomer by Reduction and Threo (±) Isomer by Inversion Method

Russian Journal of General Chemistry - We report an efficient protocol for synthesis of methyl 2-[(tert-butoxycarbonyl) amino]-3-hydroxy-3-phenylpropanoate (Erythro (±)) by simple reduction...     

Synthesis of volatile copper(II) β-diketonates, β-ketiminates, and β-diiminates. The problem of synthesis of copper(II) Bis(2,2,6,6-tetramethyl-3-methylaminoheptane-5-onate)

The methods of synthesis of the copper(II) β-diketonates, β-ketiminates, and β-diiminates containing in the composition CH₃, CF₃, C(CH₃)₃, and Ph substituents were summarized. At the formation of metallocycles with 2,2,6,6-tetramethyl-3-methylaminoheptane-5-one ligand the intraligand repulsion of tret-butyl group and the methyl group at the nitrogen atom is noted, impeding the complexation.     

Synthesis and Structure of Catena-[Bis(2-Methylimidazole)(μ-Phthalato)cobaltate(II)]

A new coordination compound [Co(Pht)(2-MeIm)₂] (I), where Pht^2–is the deprotonated radical of o-phthalic acid (H₂Pht) and 2-MeIm is 2-methylimidazole, was synthesized. Its structure was established using X-ray diffraction analysis. The crystal is orthorhombic: space group Pca2₁, a= 15.350(3), b= 7.957(2), c= 13.997(3) Å, (calcd.) = 1.505 g/cm³, and Z= 4. The tetrahedral coordination of the Co(II) atom includes two N atoms of two 2-methylimidazole molecules and two oxygen atoms of two carboxyl groups from different acid radicals. The Co–N distances are equal to 2.022(2) and 2.031(2) Å, while the Co–O distances are 1.972(2) and 2.000(2) Å. The carboxyl groups of the Pht^2–radical and the aromatic nucleus form angles of 47.2° and 35.9°, whereas the angle formed by the carboxyl groups themselves is 50.3°. Compound Iis a polymer, which is confirmed by the 1,6-bridging function of the o-phthalic acid radical. The Co···Co distance in a chain is equal to 7.367 Å. Separate chains are united in the crystal into a framework via N–H···O hydrogen bonds.     

Potential propelling and rotating functions of propeller-type complexes. II. Preparation and molecular dynamics simulation of tris(5-carboxy-2,2′-bipyridine)cobalt(III)

Isolation of four optically active isomers of the 5-substituted 2,2′-bipyridine complexes [Co(cbpy)₃]³⁺ (cbpy?=?5-carboxy-2,2′-bipyridine) was achieved using cation-exchange column chromatography (SP-Sephadex C-25) eluting with either sodium (?)-O,O′-dibenzoyltartrate or sodium ((+)-tartrato)antimonate(III). Structure optimization and molecular dynamics (MD) simulations of the system consisting of the propeller-type complex fac-[Co(cbpy-H)₃] (cbpy-H?=?2,2′-bipyridine-5-carboxylate anion) and 80 water molecules were performed using the AMBER?6 program. Results of the MD simulation revealed that distinct translating and rotating behaviors can be obtained in this complex in aqueous solution upon IR irradiation.     

The crystal and molecular structure of bis(η5-trimethylsilylcyclopentadienyl)titanium(IV) dichloride,Ti(η5-C5H4SiMe 3)2Cl2

Summary The crystal and molecular structure of the titanocene complex Ti(⁵-C₅H₄SiMe ₃)₂Cl₂ has been determined by X-ray diffraction studies. The compound crystallizes in the triclinic crystal system [a=6.747(8),b=12.815(2),c=12.928(4) Å and =67.16(2), =82.29(5), =74.83(4)°] in the space group with 2 formula units in the unit cell. The coordination about the titanium atom formed by the two chlorine atoms and the centroids of the cyclopentadienyl rings is that of a distorted tetrahedron. The Cl-Ti-Cl angle is 91.63° while the (centroid)-Ti-(centroid) angle is 131.02°.

---

Die Kristall- und Molekülstruktur von Bis(⁵-trimethylsilylcyclopentadienyl)titan(IV)dichlorid, Ti(⁵-C₅H₄SiMe ₃)₂Cl₂

Zusammenfassung Die Kristall- und Molekülstruktur des Titanocen-Komplexes Ti(⁵-C₅H₄SiMe ₃)₂Cl₂ wurde durch eine Röntgenstrukturanalyse bestimmt. Die Verbindung kristallisiert im triklinen Kristallsystem [a=6.747(8),b=12.815(2),c=12.928(4) Å und =67.16(2), =82.29(5), =74.83(4)°] in der Raumgruppe mit 2 Formeleinheiten pro Elementarzelle. Das Titanatom ist von zwei Chloratomen und den Centroiden der Cyclopentadienylringe umgeben, wobei die Koordination des Titanatoms verzerrt tetraedrisch ist. Die Winkel Cl-Ti-Cl und (Centroid)-Ti-(Centroid) betragen 91.63° bzw. 131.02°.