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1.
T. A. Kochina D. V. Vrazhnov I. S. Ignat’ev M. G. Voronkov 《Russian Journal of General Chemistry》2006,76(11):1774-1777
Transformation of the diethylsilylium cation Et2Si+H into ethyl-and dimethylsilylium ions EtSi+H2 and Me2Si+H in reactions with nucleophiles is induced by electron-donor compounds. Their activity increases in the order Bu2O < BuOH < (Me3Si)2O < C6H6 and is determined by the structure of the intermediate adduct and electron density distribution in it. Qualitative estimation shows that the affinity of the tritiated diethylsilylium cation Et2Si+T for a nucleophile increases in the order C6H6 < BuOH < Bu2O < (Me3Si)2O. The higher affinity of the Et2Si+H cation for hexamethyldisiloxane compared to dibutyl ether, at similar basicity of the nucleophiles, is attributable to the higher charge of the oxygen atom in (Me2Si)2O. 相似文献
2.
It has been shown that heterocyclic amines can be added to the activated double bond of vinylidenediphosphonic acid to form adducts with betaine structures. Of aliphatic amines only trimethylamine reacts with vinylidenediphosphonic acid.For Part 4, seeIzv. Akad. Nauk, Ser. Khim., 1992, 2180 [Bull. russ. Acad. Sci., Div. Chem. Sci., 1992,41, 1709 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1590–1592, August, 1995. 相似文献
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5.
P. V. Nikul’shin A. M. Maksimov V. E. Platonov 《Russian Journal of Organic Chemistry》2016,52(1):25-31
1,2,4-Trichlorotrifluorobenzene reacted with potassium hydrogen sulfide, potassium hydroxide, sodium isopropoxide, liquid ammonia, and ethyl cyanoacetate via nucleophilic substitution of one fluorine atom with predominant formation of the isomer in which the new substituent replaced fluorine atom in the 5-position. 相似文献
6.
η6-o-Chlorotoluene-η5-cyclopentadienyliron hexafluorophosphate undergoes nucleophilic substitution of the chlorine atom with anions generated (K2CO3/DMF) from methyl thioglycolate, diethyl malonate, dimethyl malonate, methyl acetoacetate and 2,4-pentanedione. The compounds prepared were o-CH3C6H4SCH2CO2CH3FeCp+PF6−, o-CH3C6H4CH(CO2C2H5)2FeCp+PF6−, o-CH3C6H4CH(CO2CH3)2FeCp+PF6−, o-CH3C6H4CH(COCH3)CO2CH3FeCp+PF6− and o-CH3C6H4CH2COCH3FeCp+PF6
. Similarly, the reaction of diethyl malonate, dimethyl malonate, methyl acetoacetate anions and methylamine with η6-2,6-dichlorotoluene-η5-cyclopentadienyliron hexafluorophosphate yielded monosubstitution of one of the chloro groups. The complexes prepared in this study were η6-diethyl(3-chloro-2-methyl) phenylmalonate- η5-cyclopentadienyliron hexafluorophosphate, η6-dimethyl(3-chloro-2-methyl)phenylmalonate-η5-cyclopentadienyliron hexafluorophosphate, η6-methyl(3-chloro-2-methyl)phenylacetoacetate-η5-cyclopentadienyliron hexafluorophosphate and η6-3-chloro(2-methyl-N-methyl)aniline-η5-cyclopentadienyliron hexafluorophosphate. Reaction of η6-2,6-dichlorotoluene-η5-cyclopentadienyliron hexafluorophosphate with excess methanol as well as methyl thioglycolate in the presence of K2CO3 resulted in disubstitution of both chloro groups to yield new complexes, η6-2,6-dimethoxytoluene-η5-cyclopentadienyliron hexafluorophosphate and η6-methyl[(2-methylphenyl)1,3-dithio] diacetate-η55-cyclopentadienyliron hexafluorophosphate, respectively. Complexes o-CH3C6H4CH(CO2C2H5)2FeCp+PF6−, o-CH3C6H4CH(CO2CH3)2FeCp+PF6− and o-CH3C6H4CH2 COCH3FeCp+ PF6− react with excess K2CO3 and benzyl bromide in refluxing methylene chloride to give 80–90% yields of complexes o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6−, o-CH3C6H4C(CH2C6H5)(CO2CH3)2FeCp+PF6− and o-CH3C6H4CH(CH2C6H5)COCH3FeCp+PF6−, respectively. Reaction of complex, o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6− with one molar equivalent of t-BuOK followed by acidic work-up gives o-(C2H5CO2CH2)C6H4CH(CO2C2H5)CH2C6H5FeCp+PF6−. Similarly, reactions of complexes o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6− and o-CH3C6H4C(CH2C6H5)(CO2CH3)2FeCp+PF6− with t-BuOK in THF followed by alkylation with methyl iodide gave the new complexes, o-(C2H5O2C(CH3)CH)C6H4CH(CH2C6H5)CO2C2H5FeCp+PF6− and o-(CH3O2C(CH3)CH)C6H4CH(CH2C6H5)CO2CH3FeCp+PF6−, respectively. Vacuum sublimation of the new complexes, o-CH3C6H4C(CH2C6H5)(CO2C2H5)2FeCp+PF6− and o-(C2H5O2CCH2)C6H4CH(CH2C6H5)CO2C2H5FeCp+PF6− gives o-CH3C6H4C(CH2C6H5)(CO2C2H5)2 and O-(C2H5O2CCH2)C6H4CH(CH2C6H5)CO2C2H5, respectively. 相似文献
7.
K. P. Madhusudanan Raka Jain Shubhra Mittal Susheel Durani R. S. Kapil 《Journal of mass spectrometry : JMS》1986,21(12):781-784
From a study of the reactions of nucleophiles with 1,2,3-triaryl-propenones and-butenones in a chemical ionization source it has been found that stronger nucleophiles, such as, MeO?, EtO? and MeS?, attack the α,β-unsaturated system at the β-carbon (Michael addition) or the carbonyl carbon giving rise to tetrahedral adducts, while weaker nucleophiles, such as, Cl? form the adduct ion by H-bonding with the β-hydrogen. The effect of substituents and source temperature supports the operation of these processes. The triaryl butenone did not give the adduct ion with MeO? as deprotonation leads to a stable [M ? H]? ion. 相似文献
8.
V. V. Mezheritskii A. L. Vasserman G. N. Dorofeenko 《Chemistry of Heterocyclic Compounds》1974,10(7):780-783
Nitriles, Grignard reagents, and CH-acid compounds attack the -carbon atom in -ethoxyvinylpyrylium salts to give, respectively, nitrilium salts, styrylpyrylium salts, and pyrylomerocyanines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 897–900, July, 1974. 相似文献
9.
A. A. Ladatko I. D. Sadekov L. N. Étmetchenko V. I. Minkin 《Chemistry of Heterocyclic Compounds》1989,25(5):577-580
10-Telluroniaanthracene perchlorates react with nucleophiles (X–=halide, hydroxide, methoxide) via intermediate free telluroxanthyl radicals. With 9-aryl-10-telluroniaanthracene perchlorates, high yields of 9-aryl-9-X-telluroxanthenes are obtained, but with 10-telluroniaanthracene the principal product is 9,9-bis(telluroxathenyl) as a result of rapid competitive dimerization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–695, May, 1989. 相似文献
10.
Sulfur-containing derivatives of the camphene series have been obtained by the nucleophilic addition of isothiouronium salts and thiourea under the conditions of base catalysis.S. V. Kurashov Kazan' State Medical Institute, 420012 Kazan', ul. Butlerova, 12. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 244–246, March–April, 1994. 相似文献
11.
Sulfur-containing derivatives of the camphene series have been obtained by the nucleophilic addition of isothiouronium salts
and thiourea under the conditions of base catalysis.
S. V. Kurashov Kazan' State Medical Institute, 420012 Kazan', ul. Butlerova, 12. Translated from Khimiya Prirodnykh Soedinenii,
No. 2, pp. 244–246, March–April, 1994. 相似文献
12.
Reactions of 4-chlorothiopyrylium cation (1) with a variety of nucleophiles have been investigated. Thiophenol, aniline, N-methylaniline, sodium phenoxide and sodium methoxide reacted with 1 to give 4-substituted products. On the other hand, Grignard reagents and alkyl amines afforded ring-opened products by nucleophilic attack at the 2-position. The difference in reaction position according to the kind of nucleophile can be reasonably intrepreted in terms of the principle of hard and soft acids and bases. The “aromatic character” of thiopyrylium cation is discussed on the basis of the relative reactivities in nucleophilic substitution of 1, N-methyl-4-chloropyridinium (2) and 4-chloropyrylium (8) cations. 相似文献
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Graham Pattison Graham Sandford Emma V.B. Wallace Dmitry S. Yufit Judith A.K. Howard John A. Christopher David D. Miller 《Journal of heterocyclic chemistry》2008,45(1):143-147
Nucleophilic aromatic substitution reactions of tetrachloropyridazine with a series of aliphatic primary and secondary amines led selectively to products arising from replacement of chlorine at the 4‐position in all cases. The structures of the products were unambiguously confirmed by X‐ray crystallography. Substitution occurs at the most activated site para to ring nitrogen, despite the possible steric hindrance to substitution by adjacent chlorine atoms, reflecting the activating influence of ring nitrogen meta to the site of attack. N,N′‐Dimethylethylene diamine gave a mixture of [6,6] ring fused products following initial substitution at the 4‐position. 相似文献
15.
Ya. Ya. Khomutnik P. P. Onys’ko Yu. V. Rassukanaya A. G. Vlasenko A. N. Chernega V. S. Brovarets S. G. Pil’o A. D. Sinitsa 《Russian Journal of General Chemistry》2012,82(6):1058-1064
Reactions of N-aroyltrichloroethaneimines CCl3C(R)=NCOAr (II, R = COOMe, CN) with phosphorus nucleophiles were studied. The reaction of imines II with o-phenylenediethylamidophosphite proceeded as [4+1]-cycloaddition leading to formation of stable spirocyclic phosphoranes. The structure of one of them was proved by the XRD analysis. The reaction of imine II with acyclic P(III) derivatives [Ph3P, Ph2POEt, (PhO)3P] also includes the formation of labile monocyclic phosphoranes which eliminate phosphine oxide and undergo chlorotropic transfer leading to trichloroazadienes CCl2=C(R)N=C(Cl)Ar. The reaction of imines II with (EtO)2POH in the presence of triethylamine leads to the formation of (EtO)2P(O)Cl and the corresponding dichlorovinylamides CCl2=C(R)NHCOAr. 相似文献
16.
Carbon nucleophiles were used to open a 2,2,3-trisubstituted ethynylaziridine. A cyanide nucleophile opened the ring at the more substituted carbon, proceeding regioselectively with inversion of configuration. In an attempt to expand upon the scope of the reaction, Normant cuprates were reacted with a 2,2,3-trisubstituted ethynylaziridine. This reaction produced chiral allenes via an anti-SN2′ pathway. X-ray analysis of a derivative allowed the absolute stereochemistry of the anti-allenes to be assigned as P. 相似文献
17.
《Tetrahedron letters》1987,28(40):4707-4710
Reactions of cycloalkeno-1,2,3-selenadiazole and various nucleophiles were studied. In the case of 5-membered ring fused 1,2,3-selenadiazole, nucleophilic attack on selenium atom exclusively resulted in a formation of vinyl selenide derivatives. 相似文献
18.
The review analyzes the reactions of alicyclic epoxy compounds with oxygen-containing nucleophiles (alcohols, water, and organic acids), describes biologically active products of these reactions, and discusses their mechanisms and results of their simulation by quantum-chemical methods. The regio-and stereoselectivity of nucleophilic reactions of epoxy compounds and the activation of epoxy ring by achiral and chiral catalysts are also considered. 相似文献
19.
E. V. Aleksandrova A. N. Kravchenko P. M. Kochergin 《Chemistry of Heterocyclic Compounds》2010,46(1):1-14
Published data on the reactions of 4(5)-halo-5(4)-nitro- and 2-halo-4(5)-nitroimidazoles with nucleophiles are reviewed and
classified. 相似文献