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The reactions of the isomeric dibrometetrafluorobenzenes with the methanethiolate anion and copper(I) methanethiolate have been examined. Using the thiolate anion replacement of fluorine by the SMe group occurred, but with copper(I) methanethiolate protodebromination and replacement of the bromine with the SMe group occurred. The new compounds isolated have been characterized and their spectra (NMR, IR, and mass) examined. 相似文献
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The reactions of some halogenoaromatic compounds, mainly fluoroaromatics C6FxH6-x with the methanethiolate anion have been studied in DMF or an HMPA/THF mixture. Complete replacement of fluorine occurred forming C6(SMe)xH6-x. Attempts to prepare C6(SEt)6 and compounds such as C6(SEt)2(SMe)4 are described. Other new compounds isolated included C6(SMe)5SH and C6F2(SMe)2(SEt)2. Details of the spectra, particularly NMR, are given. 相似文献
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The reactions of the fluorobenzenes, C6F5H, o-C6H2F4, m-C6H2F4, p-C6H2F4, 1,3,5-C6F3H3, 1,2,4-C6F3H3, o-C6F2H4, m-C6F2H4, p-C6F2H4 and C6F5H with thiolate anion nucleophiles RS? (primarily MeS?), have been studied in ethylene glycol/pyridine mixtures as a solvent. Multiple replacement of fluorine atoms was observed in the more highly fluorinated compounds, but in all cases two aromatic fluorine atoms were not replaced. Difluorobenzene and fluorobenzene did not react. The product orientations have been deduced from their NMR spectra. The mass spectra of the isomeric products C6F2H3(SMe), C6F3H2(SMe) and C6F2H2(SMe)2 have been examined. 相似文献
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Direct nucleophilic substitution with sodium methanethiolate of the pentafluorophenyl compounds C6F5X (X = Cl, Br, I. NO2, NH2, CO2H, SC6F5, OMe, OH) has given varying amounts of XC6F4(SMe), XC6F3(SMe)2, C6F4(SMe)2, XC6F2(SMe)3 and C6F2(SMe)4. In some cases cleavage of the aromatic carbon-X bond (X = Br, I, CO2H, SC6F5) forming C6F4(SMe)H and C6F2(SMe)3H, and the O-Me bond forming HOC6F2(SMe)3 was observed. The new compounds isolated have been characterized by elemental analyses, infrared and mass spectra and their stereochemistries have been from their 1H and 19F NMR spectra. 相似文献
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Direct nucleophilic substitution with sodium methanethiolate of the fluorinated anilines and phenylhydrazines, pentafluorophenylaniline, the three isomeric tetrafluoroanilines, pentafluorophenylhydrazine, and 2,3,5,6-tetrafluorophenylhydrazine, gave replacement of one or two fluorine atoms. The new compounds isolated have been characterized by elemental analysis, infrared and mass spectra and their stereochemistries have been deduced from their NMR spectra (1H, 19F and, in one instance, 13C). 相似文献
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Maurice E. Leblanc Michael E. Peach Heather M. Winter 《Journal of fluorine chemistry》1981,17(3):233-248
The reactions of various nitrofluorobenzenes, C6HxFyNO2, with sodium methanethiolate have been studied in ethylene glycol/pyridine mixture as solvent. All the fluorine atoms, but not the nitrogroups, could be substituted by the methylthio group. The reactions have also been studied with the addition of a deactivating group, either methyl or amino, on the aromatic nucleus. Some of the methylthio groups in the products were oxidized to the corresponding sulfones. The new compounds isolated have been characterized and their spectra (IR, NMR and mass) examined. 相似文献
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The nucleophilic substitution reactions of some simple fluorobenzenes, C6H6?xFx with sodium methanethiolates Na+SR?(R=Et, -Pr, -Bu) have been studied. Some fully substituted products, C6H6?x(SR)x, could be obtained in DMF as solvent with R = Et and -Pr, but not when R = -Bu. All the new products isolated have been characterized by elemental analysis, and NMR (H-1 and F-19), infrared and mass spectroscopy. 相似文献
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Arthur J. Elliott 《Journal of heterocyclic chemistry》1981,18(4):799-800
Benzothiohydrazide acts as a 1,4-bidentate nucleophile under basic conditions, and condenses with suitably substituted pyridines, pyrimidines and quinoxalines to yield ring-fused-1,3,4-thiadiazines un-substituted on the 4-nitrogen position. 相似文献
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A kinetic study of the reactions of thiolate ions with three Fischer-type [aryloxy(phenyl)carbene]pentacarbonyl chromium(0) complexes in 50% MeCN-50% water (v/v) is reported. Br?nsted plots of the second-order rate constants are biphasic with an initial steep rise for weakly basic thiolate ions (beta(nuc) approximately equal to 1.0) followed by a slightly descending leg with a negative slope (beta(nuc) approximately equal to -0.2) for strongly basic thiolate ions. This indicates a change from rate-limiting leaving group departure at low pK(RSH)(a) to rate-limiting nucleophilic attachment at high pK(RSH)(a). The negative beta(nuc) values result from a combination of minimal progress of C-S bond formation at the transition state and the requirement for partial desolvation of the nucleophile before it enters the transition state. Possible factors that may affect the degree of bond formation in reactions of Fischer carbene complexes as well as reactions of other unsaturated electrophiles with thiolate ions are discussed. 相似文献
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Piskunov A. V. Maslennikov S. V. Spirina I. V. Maslennikov V. P. Artemov A. N. 《Russian Journal of General Chemistry》2002,72(1):65-67
Tin was oxidized with tricarbonylcyclopentadienylmolybdenum and tricarbonylcyclopentadienyltungsten chlorides to obtain polynuclear organometallic compounds [5-C5H5M(CO)3]2SnCl2 (M = Mo, W). The reactions of the above-mentioned oxidants with lead gave lead chloride and [5-C5H5M(CO)3]2 dimers. Formal-kinetic regularities of tin oxidation with tricarbonylcyclopentadienylmolybdenum chloride in N,N-dimethylformamide were found. Thermodynamic parameters of adsorption of the reagent on the metal surface were determined. 相似文献
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Computations show how the solvated fluoride ion can be a good nucleophile in spite of its high solvation energy. 相似文献
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[reaction: see text] An efficient method for the synthesis of five-membered carbo- and heterocyclic compounds, including fused rings, was reported using acetate as a nucleophile in the cyclization of 1,6-enynes under palladium(II) catalysis. The reaction is initiated by trans-acetoxypalladation of the alkynes and quenched by either trans- or cis-deacetoxypalladation in the presence of 2,2'-bipyridine as the ligand. An example of the catalytic asymmetric cyclization is presented with moderate enantioselectivity using chiral bisoxazoline ligand. 相似文献
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Octafluorobut-2-ene is much more difficult to dimerise, with fluoride ion, than is hexafluoropropene but perfluoro-3,4-dimethylhex-3-ene is obtained under more forcing conditions. In contrast, polyfluoroalkylations with octafluorobut-2-ene are very efficient and results with perfluoro-pyridine, -pyridazine, and -quinoline are described, giving various perfluoro-2-butyl derivatives. Reactions with nitropentafluorobenzene and perfluorotoluene are also described. The 19F n.m.r. spectra of perfluoro-2-butylaromatic compounds reveal restricted rotation, even at room temperature. 相似文献
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Exposure of acetonitrile/methanol solutions of [PPN][Ru(DPPBT)3] [PPN = bis(triphenylphosphoranylidene); DPPBT = 2-diphenylphosphinobenzene thiolate] to oxygen initiates metal-centered oxidation, yielding the ruthenium(III) thiolate Ru(DPPBT)3. Ru(DPPBT)3 further reacts with oxygen, at sulfur, to give the ruthenium(III) sulfinate complex [Ru(DPPBT-O2)2(DPPBT)], which is reduced under ambient conditions to [PPN][Ru(DPPBT-O2)2(DPPBT)]. Ruthenium(II) sulfinate is the only product isolated from acetonitrile/methanol. Yellow crystals of [PPN][Ru(DPPBT-O2)2(DPPBT)] were obtained. Ruthenium(III) sulfinate was isolated as green prism-shaped crystals upon oxygenation of [PPN][Ru(DPPBT)3] in chlorobenzene/hexane. Electrochemical oxidation of ruthenium(II) sulfinate yields the ruthenium(III) derivative, which is rapidly reduced back to ruthenium(II) upon the addition of hydroxide. 相似文献
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Several aromatic compounds containing one or two C6F5S groups have been prepared by nucleophilic displacement reactions using CuSC6F5 in DMF solution. Aromatic iodine or bromine, rather than chlorine of fluorine is replaced by the SC6F5 group using CuSC6F5. A mechanism is postulated. New compounds prepared include -(C6F6F5S)2C6H4, - and -(C6F5S)2C6F4 and XC6H4SC6F5(X=C1, NO2, I, CH3, CO2C2H5). 相似文献
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Reactions of carbonate radical anion with amino-carboxylate complexes of manganese(II) and iron(III)
Amir Mizrahi Eric Maimon Haim Cohen Israel Zilbermann 《Journal of Coordination Chemistry》2018,71(11-13):1749-1760
AbstractThe reaction kinetics of eight amino-carboxylate complexes of Fe(III) and Mn(II) with carbonate radical anion were studied using the pulse radiolysis method and UV-vis spectroscopy. Difference spectra revealed the formation of Fe(IV) and Mn(III) after reaction with CO3??. Spectral measurements revealed the first step to be the coordination of carbonate to the metal center. All of these led to the conclusion that the role of coordinated carbonate is essential to the electron transfer process by carbonate radical anion. 相似文献