O,O,S-三甲基硫赶磷酸酯在甲胺磷中毒检验中的应用

利用气相色诤质谱(GC-MS)分析了甲胺磷中毒者的检材(血，胃内容物)，均检出了O，O，S-三甲基硫赶磷酸酯，确未检出过甲胺磷。研究了这一现象的原因和确定了O，O，S-三甲基硫赶磷酸酯(O，O，S-TMTP)可作为甲胺磷中毒的佐证物。     

ORGANOGERMANIUM(IV) O,O,ALKYLENEDI-THIOPHOSPHATES

Abstract

Tri- and di-organogermanium(IV) O,O-alkylenedithiophosphates R_4-n ,Ge(S₂PO₂G)_n (where R = Ph. Bu, Et. G =—C(CH₃)₂C(CH₃)₂[sbnd], [sbnd], CH₂C(CH₃)₂CH₂[sbnd], [sbnd]CH—CH₃CH₂C(CH₃)₂[sbnd], n= 1, 2) were synthesized by treatment of organogermanium(IV) chlorides with ammonium O,O-alkylenedithiophosphates in benzene. These are volatile, liquids except the phenyl ones which are solids. All of these are miscible in organic solvents and monomeric in refluxing benzene. Like dialkyldithiophosphate derivatives of organogermanium these cyclic ones also appear to be tetrahedral with the ligands behaving as unidentate ones.     

Synthesis of Pure O,O,S-Trialkyl Phosphorodithioates

Abstract

Esters of phosphorodithioic acid are of importance in pesticide formulations¹ and as oil additives.² The widely used method of preparation is to reflux the alkali metal salt of dialkyl phosphorodithioic acid with an alkyl bromide in alcoholic solution,³ i.e.     

Thermodynamics of Cr2O3, FeCr2O4, ZnCr2O4, and CoCr2O4

High-temperature heat capacity measurements were obtained for Cr₂O₃, FeCr₂O₄, ZnCr₂O₄, and CoCr₂O₄ using a differential scanning calorimeter. These data were combined with previously available, overlapping heat capacity data at temperatures up to 400 K and fitted to 5-parameter Maier–Kelley C_p(T) equations. Expressions for molar entropy were then derived by suitable integration of the Maier–Kelley equations in combination with recent S^∘(298) evaluations. Finally, a database of high-temperature equilibrium measurements on the formation of these oxides was constructed and critically evaluated. Gibbs free energies of Cr₂O₃, FeCr₂O₄, and CoCr₂O₄ were referenced by averaging the most reliable results at reference temperatures of (1100, 1400, and 1373) K, respectively, while Gibbs free energies for ZnCr₂O₄ were referenced to the results of Jacob [K.T. Jacob, Thermochim. Acta 15 (1976) 79–87] at T = 1100 K. Thermodynamic extrapolations from the high-temperature reference points to T = 298.15 K by application of the heat capacity correlations gave Δ_fG^∘(298) = (−1049.96, −1339.40, −1428.35, and −1326.75) kJ · mol⁻¹ for Cr₂O₃, FeCr₂O₄, ZnCr₂O₄, and CoCr₂O₄, respectively.     

Stability of nitrogen-oxygen cages N12O2, N14O2, N14O3, and N16O4

Molecules consisting entirely of nitrogen have been studied extensively for their potential as high energy density materials (HEDM). However, many such molecules are too unstable to serve as practical energy sources. This has prompted many studies of molecules that are mostly nitrogen but which incorporate heteroatoms into the structure to provide additional stability. In the current study, cages of three-coordinate nitrogen are viewed as candidates for stabilization by insertion of oxygen atoms into the nitrogen framework. Cages of N12, N14, and N16 with four-membered rings are studied because four-membered rings have been previously shown to be a destabilizing influence. Insertion of oxygen atoms, which converts N-N bonds to N-O-N bonding groups, relieves ring strain and can potentially result in stable molecules. These molecules are studied by theoretical calculations, using Hartree-Fock and Moller-Plesset (MP3 and MP4) theories, to determine the dissociation energies of the molecules. The primary result of the study is that stable molecules can result from oxygen insertion but that oxygen-oxygen proximity destabilizes the insertion products.     

Synthesis of O2'-methyluridine, O2'-methylcytidine, N4,O2'-dimethylcytidine and N4,N4,O2'-trimethylcytidine from a common intermediate

A facile synthesis of the title compounds from a readily accessible precursor, 3',5'-O-bis-protected O4-(2-nitrophenyl)uridine, is described.     

Total synthesis of N,O,O,O-tetraacetyl-d-ribo-phytosphingosine and its 2-epi-congener

Total synthesis of the natural d-ribo-phytosphingosine I and its 2-epimer III in the protected form was achieved through a common strategy. The aza-Claisen rearrangement of allylic thiocyanate (Z)-V incorporated the new stereogenic centre with nitrogen and the subsequent Wittig olefination constructed a non-polar side chain. Hydrogenation, followed by removal of protecting groups, completed the syntheses of I and III.     

Extraction of Gallium (III) with O,O, S-Triethyldithiophosphate

Abstract

A method is presented for the rapid solvent extraction of gallium (III) with o, o, s-triethyldithiophosphate. Quantitative extraction results from 4–9 M hydrochloric acid, using 100% extractant. The extract-able species is H[GaCl₄]·2(C₂H₅ O₂)₂ P(S)SC₂H₅.     

Structural, energetic, electronic, bonding, and vibrational properties of Ga3O, Ga3O2, Ga3O3, Ga2O3, and GaO3 clusters

The results of density functional theory based calculations on Ga3O, Ga3O2, Ga3O3, Ga2O3, and GaO3 clusters are reported here. A preference for planar arrangement of the constituent atoms maximizing the ionic interactions is found in the ground state of the clusters considered. The sequential oxidation of the metal-excess clusters increases the binding energy, but the sequential removal of a metal atom from the oxygen-excess clusters decreases the binding energy. The increase in the oxygen to metal ratio in these clusters is accompanied by increase in both electron affinity and ionization potential. The ionization induced structural distortions in the neutral clusters are relatively small, except those for Ga3O2. In anionic (cationic) clusters, the added (ionized) electron is shared by the Ga atoms, except in the case of GaO3. The vibrational frequencies and charge density analysis reveal the importance of the ionic Ga-O bond in stabilizing the gallium oxide clusters considered in this study.     

Oxidizing O,O,O-trimethyl phosphorothioate with hydrogen peroxide or ozone

Oxidization of O,O,O-trimethyl phosphorothioate to the corresponding oxo (P=O) compound is accomplished under mild conditions with hydrogen peroxide or ozone. Urea hydroperoxide was found to be a serviceable solid-state source of hydrogen peroxide; it was a better oxidizing agent than 30% hydrogen peroxide and resulted in better yield. It was also proved that ozone was the most effective oxidizer, with formation of purer products in higher yield (90.1%) than with hydrogen peroxide.     

Synthesis and Characterization of O,S-Dimethylphosphoramidothioate and N-Acetyl O,S-Dimethylphosphoramidothioate

O,S-Dimethylphosphoramidothioate (methamidophos) and N-acetyl O,S-dimethylphos- phoramidothioate (acephate) were synthesized by new methods to investigate the structure–activity study of acetyl cholinesterase (AChE) inhibition through the parameters of logP, δ ³¹P, and IC₅₀. After their characterization by NMR (³¹P, ³¹P{ ¹H}, ¹³C, and ¹H), IR, and mass spectroscopy, logP and δ ³¹P (³¹P chemical shift in NMR) were used to evaluate lipophilicity and electronical properties. The logP values for methamidophos and acephate were experimentally determined by the GC-shake-flask method, and the ability of the compounds to inhibit human AChE was evaluated by a modified Ellman's assay.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Ab initio calculations of nitrogen oxide reactions: formation of N2O2, N2O3, N2O4, N2O5, and N4O2 from NO, NO2, NO3, and N2O

Ab initio computational methods were used to obtain Delta(r)H(o), Delta(r)G(o), and Delta(r)S(o) for the reactions 2 NO <=> N(2)O(2) (I), NO+NO(2) <=> N(2)O(3) (II), 2 NO(2) <=> N(2)O(4) (III), NO(2)+NO(3) <=> N(2)O(5) (IV), and 2 N(2)O <=> N(4)O(2) (V) at 298.15 K. Optimized geometries and frequencies were obtained at the CCSD(T) level for all molecules except for NO, NO(2), and NO(3), for which UCCSD(T) was used. In all cases the aug-cc-pVDZ (avdz) basis set was employed. The electronic energies of all species were obtained from complete basis set extrapolations (to aug-cc-pV5Z) using five different extrapolation methods. The [U]CCSD(T)/avdz geometries and frequencies of the N(x)O(y) compounds are compared with literature values, and problems associated with the values and assignments of low-frequency modes are discussed. The standard entropies are compared with values cited in the NIST/JANAF tables [NIST-JANAF Thermochemical Tables, J. Phys. Chem. Ref. Data Monograph No. 9, 4th ed. edited by M. W. Chase, Jr. (American Chemical Society and American Institute of Physics, Woodbury, NY, 1988)]. With the exception of I, in which the dimer is weakly bound, and V, for which thermodynamic data appears to be lacking, the calculated standard thermodynamic functions of reaction are in good agreement with literature values obtained both from statistical mechanical and various equilibrium methods. A multireference-configuration interaction calculation (MRCI+Q) for I provides a D(e) value that is consistent with previous calculations. The combined uncertainties of the NIST/JANAF values for Delta(r)H(o), Delta(r)G(o), and Delta(r)S(o) of II, III, and IV are discussed. The potential surface for the dissociation of N(2)O(4) was explored using multireference methods. No evidence of a barrier to dissociation was found.