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亚磷酸二正丙酯的气相色谱法测定 总被引:5,自引:1,他引:4
采用气相色谱法分离和测定合成有机磷农药的中间体亚磷酸二正丙酯。试验结果表明,在 5% OV- 7/Chromosorb W- AW DMCS( 0.231~ 0.387 mm)的色谱柱上,亚磷酸二正丙酯与内标物联苯等之间具有较好的分离效果。并且,以联苯为内标物时,亚磷酸二正丙酯的质量校正因子相当稳定,fW. A=2.47± 0.09(α =0.05,n=5)。该法操作简便、快速,准确度和精密度较好,对同一试样的 5次平行独立测定的相对标准偏差( RSD)为 1.57%;该法的标准加入回收率达 99.2%~ 101.9%。 相似文献
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热脱附气相色谱-质谱联机定性定量分析气体中的亚磷酸三甲酯 总被引:3,自引:0,他引:3
1引言亚磷酸三甲酯(简称三甲酯)是生产有机磷农药久效磷、磷胶等的主要原料。该物质嗅阈值极低,有很强的刺激性气味。工业生产中如有小县泄漏就会使周围环境产生难闻的气昧,目前尚未见到定性、定量测定大气中三甲酯的分析方法。本文研究了用固体吸附、热脱附气相色谱质谱联用分析气体中三甲酯,为污染事故的查出及污染物的监测提供了灵敏度高、准确性好的方法。2实验被分2.1仪器与试剂Varian34O0气相色谱一Finnigan离子阶质谱一IBM电子计算机。8701A热解吸浓缩进样装置(上海分析仪器厂无锡分厂)。上分103型气相层析仪。GB-6A大… 相似文献
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有机相中乙酸-α-氰基-3-苯氧基苄酯的含量与对映体过量值的测定 总被引:1,自引:0,他引:1
光学活性的(S)-乙酸-α-氰基-3-苯氧基苄酯(CPB乙酸酯)是生物农药拟除虫菊酯的重要中间体。研究CPB乙酸酯的合成反应动力学在理论上有重要意义,在实际生产中也可为提高该中间产物的产量提供理论指导。迄今用毛细管气相色谱法测定CPB乙酸酯的含量,尚未见报道。CPB乙酸酯具有立体选择性,为了探讨有机相中脂肪酶催化的该合成 相似文献
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利用Pd(O)催化下R~2R~3P(O)H(R~2,R~3=烷基、芳基、烷氧基)与芳基溴,烯基溴以及丁二烯反应合成芳基、烯基和烯丙基膦酸酯近年来有较多报道,但后者产率仅为10%。Fiaud曾报道了二苯基膦锂和醋酸烯丙酯的反应,但烯丙基膦化合物产率低于15%。我们曾发现醋酸烯丙酯在O,N-二(三甲硅基)乙酰胺(BSA)存在下,用Ni(cod)_3为催化剂与亚磷酸二酯反应,高产率地得到了烯丙基膦酸酯,而Pd(PPh_3)_4不能催化这个反应。我们认为反应的关键是亚磷酸二酯首先与BSA反应生成O,O-二烷基-O-三甲硅基亚磷酸酯 相似文献
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《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2343-2348
A simple method for the preparation of industrially important alkyl aryl ethers is reported. Several phenolic compounds such as phenols, naphthols, and hydroxy coumarins were O-methylated with trimethyl phosphite or trimethyl phosphate under microwave irradiation and solvent-free condition in almost quantitative yields. Reaction of 2-naphthol with trimethyl phosphate gave mixture of 2-methoxynaphthalene and 1-methyl-2-methoxynaphthalene while the reaction with trimethyl phosphite gave mostly 2-methoxynaphthalene. This method is highly efficient for the methylating of phenolic compounds with very easy experimental procedure and environmental friendly conditions. 相似文献
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Yuen-Ki Cheong 《Tetrahedron》2008,64(10):2329-2338
Dimethyl 2-acetoxy- and dimethyl 2-benzoyloxy-benzoylphosphonate undergo cyclisation and deoxygenation in the presence of excess trimethyl phosphite to give dimethyl (3-methyl-1-benzofuran-2-yl)phosphonate and dimethyl (3-phenyl-1-benzofuran-2-yl)phosphonate, respectively. The reaction pathway has been shown to involve phosphite attack on initially formed tricyclic dioxaphospholane intermediates with the subsequent loss of two molecules of trimethyl phosphate. In the absence of additional trimethyl phosphite the initially formed tricyclic dioxaphospholane intermediates lose one molecule of trimethyl phosphate and then undergo a novel rearrangement to give β-ketophosphonates. The mechanism for this reaction helps explain some previously reported epoxide rearrangements. In contrast, the initially formed anionic intermediate from the reaction of dimethyl 2-benzoyloxymethylbenzoylphosphonate with trimethyl phosphite undergoes decomposition to give a carbene intermediate which is trapped by the trimethyl phosphite to give an ylidic phosphonate. 相似文献
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L. M. Pevzner 《Russian Journal of General Chemistry》2007,77(1):111-115
Ethyl 2-methylfuran-3-carboxylate is smoothly chloroethylated at 0°C in the 5 position of the ring. The resulting halide alkylates secondary amines but eliminates HCl with sodium diethyl phosphite under the Michaelis-Becker reaction conditions and with trimethyl phosphite under the Arbuzov reaction conditions. In the reaction with sodium diethyl phosphite, small amounts of 5-[1-(diethoxyphosphoryl)ethyl]furan-3-carboxylate and 5-ethylfuran-3-carboxylate are formed. In the Arbuzov reaction at a 1: 1.22 furan: trimethyl phosphite molar ratio, methyl 2,4-dimethyl-1-methoxy-1-oxo-1λ5-1,2-dihydrophospheto[3,2-b]furan-5-carboxylate was isolated. 相似文献
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Gal JF Herreros M Maria PC Operti L Pettigiani C Rabezzana R Vaglio GA 《Journal of mass spectrometry : JMS》1999,34(12):1296-1302
Self-condensation ion-molecule reactions of trimethyl phosphite, triethyl phosphite, dimethyl phosphonate, trimethyl phosphate and 2, 2-dichlorovinyl dimethyl phosphate (dichlorvos) were investigated by ion trap mass spectrometry and Fourier transform ion cyclotron resonance mass spectrometry. Reaction paths for the main processes observed were elucidated by parent ion selection and for reaction times up to 500 ms. In parallel, high-resolution measurements were performed in order to determine the composition of the principal ions. Among the compounds under examination, trimethyl phosphite and triethyl phosphite mainly give [M + H](+) and [M + (RO)(2)P](+) (R = CH(3), C(2)H(5)) adduct ions, whereas trimethyl phosphate and dimethyl phosphonate display [2M + H](+) ions, as the only abundant products, formed by reaction of [M + H](+) and M. 2,2-Dichlorovinyl dimethyl phosphate mostly shows fragmentation processes. The reaction patterns of the compounds examined were related to their different structural features. Gas-phase basicities of the phosphoryl compounds were also determined or re-examined. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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György Keglevich Imre Petneházy László Tőke Harry R. Hudson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-4):341-349
Abstract α-Hydroxyphosphonates are formed, in addition to vinyl phosphates and dehalogenated ketones, in the reactions of trimethyl phosphite (in methanol) or triethyl phosphite (in ethanol) with variously substituted α-chloro, α-bromo, and α,α-dichloro-acetophenones. Tri-isopropyl phosphite in propan-2-ol gives only the vinyl phosphate. Ketophosphonates are not detectable amongst the reaction products under the conditions used. Trends in product composition can be correlated with the leaving ability of halogen, substituent effects, structure of the phosphite, and reaction temperature. Additional products are obtained in the reactions of trimethyl phosphite in methanol with 4-nitro-α-chloroacetophenone, which gives the dehalogenated hydroxyphosphonate, and with the α,α-dichloroacetophenones which undergo monodehalogenation. Twenty three new α-hydroxyphosphonates are reported. 相似文献
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The reaction of dimethyl acetylenedicarboxylate (DMAD) with 2-naphthol in the presence of trimethyl or triphenyl phosphite leads to stable dimethyl oxa-2 lambda 5-phosphaphenanthrene derivatives in good yields. The reaction of DMAD and trimethyl phosphite in the presence of 1-naphthol or 8-hydroxyquinoline leads to dimethyl 2-(dimethoxyphosphoryl)-3-(1-hydroxy-2-naphthyl)succinate or dimethyl 2-(dimethoxyphosphoryl)-3-(8-hydroxyquinolin-7-yl)-succinate in excellent yields. Using triethyl phosphite and DMAD in the presence of 2-naphthol or 1-naphthol produces methyl 3-oxo-2,3-dihydro-1H-benzo[f]chromene-1-carboxylate or methyl 2-oxo-3,4-dihydro-2H-benzo[h]-chromene-4-carboxylate in excellent yields. 相似文献
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P. A. Chopard 《Helvetica chimica acta》1967,50(4):1021-1027
In acetic acid, trimethyl phosphite dealkylates and simultaneously forms dimethyl (1-dimethoxyphosphono-ethyl) phosphate. This is interpreted as evidence of an attack at the carbonyl group of the carboxylic acid. 相似文献
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Ethyl 5-isobutyl-2-methylfuran-3-carboxylate is selectively brominated with N-bromosuccin-imide by the methyl group to give an unstable bromide. The latter on heating or in the presence of bases un-dergoes dehydrobromination accompanied by rearrangement, leading to a (2'2-dimethylvinyl)furan derivative.Phosphorylation of this bromide with trimethyl phosphite gives a 2-dimethoxyphosphorylmethyl derivativeand a product containing the phosphonate group to the isobutyl radical. Chloromethylation of the startingester proceeds in the 4 position of the furan ring. The resulting chloride undergoes phosphorylation underconditions of the Michaelis-Becker reaction to give the corresponding 4-(dialkoxyphosphorylmethyl)furan'and under the action of trimethyl phosphite a mixture of the same phosphonate, a dehalogenation producthaving a dimethylvinyl fragment. Bromination of the 4-chloromethyl derivative with N-bromosuccinimideinvolves the 2-methyl group. The dihalide reacts with trimethyl phosphite by way of reduction of the bromomethyl group to give 4-chloromethyl- or 4-dimethoxyphosphorylmethyl derivatives, as well as analogous dehydrohalogenation products containing a 5-dimethylvinyl fragment. A scheme describing the sequence of formation of these products in the course of the reaction is offered. 相似文献
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A simple,efficient,and general method has been developed for the one-pot,three-component synthesis ofα-aminophosphonates from condensation reaction of trimethyl phosphite,aryl aldehydes and aryl amines in the presence of CoCl2-6H2O under solvent-free conditions.Thusα-aminophosphonates were synthesized relatively quickly in good yields at room temperature. 相似文献
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Gerard M. Anderson James H. Cameron A.Graham Lappin John M. Winfield Alexander McAuley 《Polyhedron》1982,1(5):467-470
Reduction of the solvated copper(II) cation by trimethyl phosphite in acetonitrile occurs via a short-lived purple intermediate believed to be a copper(II)-phosphite complex. 相似文献