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1.
The reaction of nitrilium salts with azides allows the synthesis with good yields of 1,4,5-alkyl or -aryl-substituted tetrazolium salts. The mechanism of this reaction is discussed. Reduction or alkylation of these tetrazolium salts leads to the corresponding tri- or tetra-substituted tetrazolines. 相似文献
2.
A new and general method for preparing Fischer-type alkoxycarbene complexes 1 is reported. This method involves the alkylation of acylate complexes 7 with alkyldiphenylsulfonium salts 10 with a variety of functionalized alkyl groups. The alkylation of tetramethylammonium pentacarbonyl(1-oxyalkylidene)chromate(0) 7a-c, tetramethylammonium pentacarbonyl(1-oxymethylidene)molybdate(0) 7d, and pentacarbonyl(1-oxymethylidene)tungstate(0) 7e with alkyldiphenylsulfonium salts 10 proceeded smoothly under mild conditions to give the corresponding alkoxycarbene complexes 12-39 in good to high yields. Competitive alkylation of 7a with methyl-11 and isopropyldiphenylsulfonium tetrafluoroborate 40 shows a higher reactivity of the isopropyl group, suggesting the participation of an S-O sulfurane intermediate 41. 相似文献
3.
《Tetrahedron letters》1988,29(47):6079-6082
The highly stereoselective alkylation (% de=99.6 to 97.6) of a new chiral glycine enolate synthon derived from D-2-phenylglycinol is described. Deprotection of the alkylation adducts in a one-pot three-step procedure provides the ethyl ester hydrochloride salts of the corresponding α-amino acids with no attending racemization. 相似文献
4.
The reaction of salts of 5-nitroaminotetrazole, 1- and 2-methyl-5-nitroaminotetrazole, and 2-ethyl-5-nitroaminotetrazole with alkyl iodides is studied. It is established that salts of 2-methyl- and 2-ethyl-5-nitroaminotetrazole are alkylated at the nitroamine group while salts of 1-methyl-5-nitroaminotetrazole are alkylated at the second nitrogen atom of the tetrazole fragment with the subsequent splitting off of the methyl group at the 1-position of the tetrazole ring and further alkylation of the nitroamine group. It is shown that salts of 5-nitroaminotetrazole are initally alkylated at the second nitrogen atom of the tetrazole fragment and then at the nitroamine group. It is hypothesized that the initial alkylation of salts of 1-methyl-5-nitroaminotetrazole and 5-nitroaminotetrazole at the second nitrogen atom of the tetrazole fragment results from their nitroimino tautomeric form.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1090–1093, August, 1986. 相似文献
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7.
The stereoselectivity in the alkylation of sulfonium salts is attributed to the formation of an intermediate lithio-sulfonium salt rather than a free ylid. 相似文献
8.
Two readily available and different quaternary ammonium salts have been prepared by the alkylation of vinamidinium salt reduction products. These salts have been successfully converted to 2-aryl-1-cyano-1-propenes and this methodology represents a clean and efficient procedure for the construction of such systems. 相似文献
9.
D. A. Oparin 《Chemistry of Heterocyclic Compounds》1987,23(2):165-168
Stable 1-ethylthioisoindolinium salts were obtained by alkylation of 2-phenyl-3,3-diaryl-1-thiophthalimidines with triethyloxonium tetrafluoroborate. The reactions of these salts with O-, N-, and C-nucleophiles were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 199–202, February, 1987. 相似文献
10.
Grzegorz Mlostoń Jarosław Romański Marcin Jasiński Heinz Heimgartner 《Tetrahedron: Asymmetry》2009,20(9):1073-1080
New 1-alkoxy-3-alkyl-4,5-dimethylimidazolium bromides were synthesized by alkylation of the corresponding 1-alkylimidazole 3-oxides, which were conveniently prepared via condensation of α-(hydroxyimino)ketones, primary aliphatic amines, and formaldehyde. By using enantiomerically pure chiral amines, optically active imidazolium salts were obtained. Treatment with sodium tetrafluoroborate in acetone yielded the corresponding imidazolium tetrafluoroborates. All these compounds, with only one exception, were obtained as oils, which are considered as potential ionic liquids and ‘chiral ionic liquids’. The reduction of the chiral or non-chiral 1-alkylimidazole 3-oxides with Raney-Ni, followed by alkylation with alkyl bromides and subsequent ion exchange to tetrafluoroborates, gave the corresponding 1,3-dialkylimidazolium salts, most of them showing properties of ionic liquids. The alkylation of 1-butyl-4,5-dimethylimidazole 3-oxide and the corresponding imidazole, respectively, with 1,3-dibromopropane led to the first bis-imidazolium dibromides and bis-tetrafluoroborates. 相似文献
11.
A. I. Glushkov O. P. Shitov A. V. Mezhenin V. A. Tartakovsky 《Russian Chemical Bulletin》2002,51(7):1331-1334
A method for the synthesis of 1,3,5-trisubstituted 1,2,4-triazolio-4-nitroimides was developed. The method is based on the alkylation of the corresponding salts of 3,5-disubstituted 4-nitramino-1,2,4-triazoles. 相似文献
12.
Yu. V. Bakhtiyarova R. R. Minnullin D. I. Bakhtiyarov M. V. Morozov K. A. Ivshin I. V. Galkina O. N. Kataeva V. I. Galkin 《Russian Journal of General Chemistry》2017,87(12):2789-2793
The new alkylation reactions of a series of mono- and dicarboxylate phosphabetaines with methyl and ethyl iodides in different solvents have been studied. These reactions have afforded stable compounds: iodine-containing salts of phosphonium with different structure. 相似文献
13.
Russian Journal of General Chemistry - Preparation of salicylic and acetylsalicylic acid esters via esterification and alkylation of the salts with alkyl halides has been examined. The effect of... 相似文献
14.
Sanjeev Kumar 《Tetrahedron》2005,61(29):7022-7028
We report herein, the influence of substituted aryl groups in quaternary ammonium salts derived from cinchona alkaloids on enantioselectivity of the alkylation of glycine ester enolates. 相似文献
15.
A. V. Kuchin A. Yu. Spivak G. A. Tolstikov V. N. Yur'ev 《Russian Chemical Bulletin》1982,31(4):803-806
Conclusions A study was carried out on the alkylation of trimethylchloro- and dimethyldichlorosilanes by higher trialkylaluminums containing linear and cycloalkenyl groups and a bulky alicyclic group. The catalytic effect of transition metal salts was studied for the alkylation reaction in the case of trihexylaluminum; TiCl4 was found to demonstrate the greatest activity.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 910–913, April, 1982. 相似文献
16.
[structure: see text] The Cinchona alkaloid-derived quaternary ammonium salts containing 2'-N-oxypyridine and 2'-cyanobenzene moieties were prepared and evaluated as phase-transfer catalysts in the enantioselective alkylation of glycine imine ester 1. The N-oxypyridine and cyanobenzene moieties might play an important role to form a rigid conformation by coordinating with H(2)O via hydrogen bonding leading to high enantioselectivity (97 approximately >99% ee), which provides evidence of an electronic factor for the high enantioselective catalytic efficiency in phase-transfer alkylation. 相似文献
17.
Kim Dmitry G. Kalita Elena V. Sharutin Vladimir V. Ovchinnikova Irina G. Ezhikova Marina А. Kodess Mikhail I. Slepukhin Pavel А. Vasilenko Anna V. 《Chemistry of Heterocyclic Compounds》2019,55(6):566-572
Chemistry of Heterocyclic Compounds - The sequence of condensation, alkylation, and halocyclization reactions during the synthesis of the target 2,3-dihydro[1,3]oxazolo[3,2-a]-pyridinium salts was... 相似文献
18.
R. I. Yurchenko Yu. M. Klimko A. A. Esipenko E. D. Butova A. G. Yurchenko 《Russian Journal of General Chemistry》2009,79(8):1632-1634
By reaction of di(adamant-1-yl) and di(adamant-2-yl) phosphites with sulfur in the presence of triethylamine diadamantylthiophosphoric
acid triethylammonium salts were obtained. The latter by the action of hydrochloric acid were converted into free thiophosphoric
acids and by the reaction of alkylation into the respective triesters which have thionic structure. Applicability in such
reactions also of triethylammonium salts of diadamantyldithiophosphoric acids was demonstrated. 相似文献
19.
N. P. Ramzaeva I. N. Goncharova M. Yu. Lidak Yu. Sh. Gol'dberg M. V. Shimanskaya 《Chemistry of Heterocyclic Compounds》1987,23(1):93-98
The mixture of 9-, 3-, and 7-benzyl-6-substituted purines is formed in almost quantitative yield by the alkylation of 6-benzylamino-, 6-furfurylamino-, 6-methylthio-, and 6-chloropurine with benzyl halides in the biphasic system of the liquid-liquid or liquid-solid type in the presence of interphase catalysts (quaternary ammonium salts, 18-crown-6). The catalytic activity of the quaternary ammonium salts increases with the increase in the lipophilicity of the cation. Taking the alkylation of 6-benzylaminopurine as an example, the possibility of the application of triphasic catalysis in the alkylation reaction of purines is indicated. The alkylation of 6-substituted purines with isopropyl bromide proceeds regioselectively under the conditions of the interphase catalysis with the formation of the corresponding 9-isopropylpurines.For the preliminary communication, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 113–118, January, 1987. 相似文献
20.
Shitov O. P. Korolev V. L. Bogdanov V. S. Tartakovsky V. A. 《Russian Chemical Bulletin》2003,52(3):695-699
A method for the synthesis of 1-alkyl-1,2,4-triazolium 4-nitroimides was developed based on alkylation of 4-nitramino-1,2,4-triazole Na and Ag salts with halo- and dihaloalkanes. 相似文献