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1.
T. A. Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2-3):211-229
Abstract Reactions of phosphorus monothio acids with diazomethane, diazoacetone, diphenyldiazomethane, and diazofluorene have been studied. The ratio of the yields of the S- and O-derivatives QS/QO has been found to be dependent on three factors: i) the nature of substituents at phosphorus - with electron-donor substituents raising the O-derivative yield and the quantity log (QS/QO) varying as εσ of the substituents; (ii) stability of alkyldiazonium and carbocation - with QO increasing with the carbocation stability; and (iii) polarity of the medium - the O-derivative yield rises with dielectric permeability of the medium and QS/QO has been found to be a linear function of 1/D. The most probable mechanism has been established as proton transfer from the acid to the diazocompound followed be formation of the S-derivative and the O-derivative. The former results from an SN2 reaction of the alkyldiazonium cation with the thiol-thione anion within the ion pair. The O-derivative arises from the thiol-thion anion and the carbocation; the latter resulting from decomposition of the alkyldiazonium cation within the ion pair. 相似文献
2.
《Analytical letters》2012,45(15):963-967
Abstract The separation of 13 isonicotinoyl hydrazones derived from some isomeric aromatic carbonyl compounds by thin layer chromatography is described. Methods for separating and identifying the components of complex mixtures of these hydrazones are discussed. 相似文献
3.
Bjarne S. Pedersen Sten Scheibye Sven-Olov Lawesson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):235-236
Abstract Recent studies on thiation of carbonyl compounds with organic P,S-compounds have shown that p-methoxyphenyl-thionophosphinsulfide (1) is the most effective thiation reagent for ketones, carboxamides, esters, and thioloesters hitherto known. 相似文献
4.
Abstract Saturated 1,3-dioxacyclanes under acid catalysis conditions react with thiods forming thioacetals and glycols. The effect of the type of catalysts, structure of reagents and regime parameters on the direaction and selectivity of the process was studies. 相似文献
5.
J. Michalski J. Chojnowski B. Jezierska B. Borecka 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):263-268
Abstract Reactions of hexamethyldisilathiane with oxophosphoranesulfenyl chlorides, oxophosphorane sulfenates and bis-phosphoranyldisulfides were studied. These processes lead to mono o-silyl thionesters of phosphorus. The mechanistic pathways are discussed. 相似文献
6.
研究了邻芳族羟基羰基化合物的Kishner-Wolff改良法还原,并讨论了它们的反应机制.萘酚系羰基化合物5与6中的R为H或C6H5(5a、6a、6b)时,还原后得高得率的正常还原物;如R为C6H5CH2,C6H6CH2CH2(5b、5c、6c),则除得正常还原物外,还得含氮环化物;如R为CH3、CH3CH2、CH3CH2CH2、(CH3)2CH(5d~g),则同时得正常还原物及含氮环化物,增加R中碳原子数,似乎使正常还原物减少,而含氮环化物增加.当R为CH3(CH2)6(5h),则仅得含氮环化物.苯酚系羰基化合物7中的R为烷烃基或芳族基时,均得高得率的正常还原物. 相似文献
7.
Jaroslav Kovác Jolana Kováčoá 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):173-174
Abstract Thiourea and its derivatives easily form the complexes with compounds of CuII, FeIII, PtIV etc. By the formation of complexes as a rule redoxprocess proceeds to give an appropriate thiourea disulphide. It has been shown, that redoxprocess goes on prejudice on the derivatives of thiourea in that case when the thion-thiol tautomerism is possible. 相似文献
8.
Martin Anderson Antony G. Brinnand 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract A wide range of 2-substituted-5,6-dihydro-4H-1,3-thiazines (I) and tetrahydro-2H-1,3-thiazines (II) have been found to undergo a facile ring transformation reaction with aliphatic diamines to form the corresponding dinitrogen heterocycles (III) and (IV). 相似文献
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Paul D. Beer Robert C. Edwards C. Dennis Hall J. R. Jennings R. J. Cozens 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):283-295
Abstract The reactions of a variety of trico-ordinate phosphorus compounds, Ar n P(OR)3-n (n = 1 or 2), and cyclic analogues, with acrylonitrile, ethyl acrylate or ethyl phenylpropiolate and alcohols or phenols in low polarity media gives rise to a wide range of pentaco-ordinate phosphorus compounds. Attempts to extend this synthetic route to phosphoranes containing P[sbnd]N or P[sbnd]S bonds met with no success. 相似文献
11.
Abdelhamid Elias M. Amine Didi Didier Villemin T. Semaoune S. Ouattas 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2599-2607
The reactions of phosphorus pentoxide with two alcohols and one phenol were performed in different conditions under microwave irradiation. The products (alkylphosphates and dialkylphosphates) were identical to those formed by classic heating and were obtained with better yields. The speed of the reaction was increased by a factor from 100 to 4000. 相似文献
12.
This paper reports a new method for oxidizing the α-methyl orα-methylene groups in carbonyl compounds into 1,2-dicarbonyl compoundsby ammonium chlorochromate(ACC). 相似文献
13.
Mahfouz A. Abdelaziz Bahia Y. Riad 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):303-309
Abstract 5-Arylidene-2-thiohydantoins (la-c) and 5-arylazo-1-phenyl-2-thiohydantoins (7a, b) were condensed with formaldehyde and primary or secondary aromatic amines to give the corresponding Mannich bases (2a-f) and (8a, b) respectively, which could also be converted into the educts (la-c) and (7a, b) by boiling in ethanolic HCI. On treatment of (2a-f), (5a-c) and (8a, b) with an ethereal diazomethane the colourless cyclopropane products (3a-c) and yellow N-methyl substituted compounds (9, b) were isolated respectively. Alkylation of (2d-f) with methyl iodide and (la-e) with 3-chloropentane-2,4 dione gave the corresponding 2-alkylmercapto derivatives (5a-c) and (2a-c) respectively, the former of which on hydrolysis by boiling ethanolic HCI afforded the hydantoin derivatives (6a-c). Cyclization of (12a-c) using polyphosphoric acid resulted in the formation of imidazothiazole derivatives (13a-c). The structure of the isolated products were established by elemental analyses and spectral data studies. 相似文献
14.
In this article we have proposed two topological rules to account for the electronic structures of transition-metal carbonyl compounds. The second rule is applied to those which have polyhedral metalhc skeletons with triangular faces and their derivates, while the first rule is applied to all the others We have used these two rules to analyze 261 structure-known compounds with the number of metal atoms from 2 to 12, and the results show that the two rules are in good agreement with the experimental facts. Furthermore, we have also derived from the second rule a formula which can be used to account for the electronic structures of closedpacking carbonyl compounds and which is the same as that given by Ciani and his coworkers. 相似文献
15.
Ratajczak等研究了S-(1-二茂铁烷基)疏代乙醇酸的合成与反应Ugi等将它们与羟胺反应,合成了一种有用的手性模板试剂。最近,Czech等用键合载体液相色谱对它们进行了光学拆分研究。本文报导了此类化合物与胺的反应,合成了一类新的化合物-S-(1-二茂铁烷基)硫代乙醇酸胺。 相似文献
16.
Abstract— Ultraviolet excitation of pyrimidine derivatives in aqueous solutions containing acrylonitrile can lead to polymerisation of acrylonitrile and/or photoaddition reactions of acrylonitrile and the pyrimidine. Polymerisation of acrylonitrile induced by excitation of orotic acid occurs even in aerated solutions and is very likely due to radicals derived from excited orotic acid molecuies. Using 14 C-labelied orotic acid, the polymer is shown to contain the pyrimidine. With other pyrimidine derivatives, polymerisation is observed only in deaerated solutions and its low yield did not allow us to determine whether the polymerisation is induced by radicals or by photosensitisation. The role of the lowest excited singlet and triplet states of the pyrimidine derivatives in the photoaddition reaction is discussed. In the case of orotic acid, photoaddition is shown to proceed entirely by way of the triplet state. 相似文献
17.
Ratajczak等研究了S-(1-二茂铁烷基)疏代乙醇酸的合成与反应(?)Ugi等将它们与羟胺反应,合成了一种有用的手性模板试剂。最近,Czech等用键合载体液相色谱对它们进行了光学拆分研究。本文报导了此类化合物与胺的反应,合成了一类新的化合物(?)二茂铁烷基)硫代乙醇酸胺。 相似文献
18.
Jean-Marie Catel Yves Mollier 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract The 3-methylthio-1. 2-dithiolylium including at 5 position a donor substituent, in acetic acid in the presence of pyridine, the 2-methylthio-1. 3-dithiolylium ions in methylene chloride-triethylamine, react with the 2-butene nitrile derivatives and lead to the (A) and (B) corresponding 4-dithiolylidene-2-butene nitriles. In contrast ring opening reaction of the 1, 2-dithiole is observed when 2-cyano-3-phenyl-2-butene nitrile reacts with the 3-methylthio-4-aryl-1. 2-dithiolylium ions in 3 and 5 positions, in methylene chloride-triethylamine. The nucleophilic attack on the 5 position of the dithiolylium ion leads to a 2-cyano-3-phenyl-3 (4-aryl-5-methylthio-2-thienyl) propene nitrile (C), meanwhile the attack on the 3 position leads to a 2-cyano-3-phenyl-3-(4-aryl-3-mercapto-2-thienyl) propene nitrile (D). The proposed structures are established by means of physical methods (IR, NMR, and Mass Spectrometry) and by non ambiguous synthesis. The reactivities of the various sites are explained in function of the electronic and steric effects, furthermore the reaction conditions and the intermediary isolation allow to propose the mecanisms of these reactions. 相似文献
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《Journal of Coordination Chemistry》2012,65(1-3):65-78
Abstract Metal carbonyl anions exhibit one- and two-electron reactions. The two-electron processes involving transfer of groups (hydrogen, alkyl, and halogen) between metal centers are related to the nucleophilicity. The one-electron processes are primarily outer-sphere electron transfer for the metal carbonyl anions. These reactions are observed in the presence of oxidants such as coordination complexes, pyridinium salts, metal carbonyl dimers and metal carbonyl clusters. However, in contrast to organic reactions, the metal carbonyl anions may undergo inner-sphere electron transfer. Reactions of metal carbonyl anions of low nucleophilicity with metal carbonyl cations or halides are best interpreted as inner-sphere, one-electron transfer. 相似文献