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1.
2.
A. V. Vypirailenko I. B. Dzvinchuk M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2003,39(1):123-125
2-Phenacylbenzothiazole reacts with hydrazines and o-hydroxybenzaldehydes to give hydrazones and chalcones. These compounds tend to isomerize to benzothiazole-2-spiro-3'-pyrazoles and benzo[b]pyran-2-spiro-2'-benzothiazoles, respectively. 相似文献
3.
V. V. Dovlatyan K. A. Eliazyan V. A. Pivazyan A. P. Engoyan 《Chemistry of Heterocyclic Compounds》2003,39(9):1238-1241
We have carried out solvolysis of the previously described ethyl esters of 3-methyl(aryl)-4-methyl-2-thioxothiazoline-5-carboxylic acids, leading to the corresponding acids without breaking down the heterocycle. We synthesized a series of novel esters from the latter by treatment with dimethyl sulfate or reactive halides. Of these, only in the case of the ethyl ester of 3,4-dimethyl-2-thioxothiazoline-5-carboxylic acid did we obtain the hydrazinolysis product (the hydrazide), from which we synthesized novel hydrazones by treatment with aldehydes and ketones. 相似文献
4.
A. A. Avetissian G. G. Tokmajian L. V. Karapetian 《Chemistry of Heterocyclic Compounds》2005,41(7):841-844
The reaction of 3-acetyl-4,6,6-trimethyl-5,6-dihydro-2-pyrone with the hydrazides of a series of carboxylic acids led to the
synthesis of 5-alkyl(cyanomethyl)carbonyl-3,5a,7,7-tetramethylpyrazolino-4,5-c]tetrahydro-2-pyrones, which are the products
from cyclization of the intermediately formed alkyl(cyanomethyl)hydrazones of 3-acetyl-4,6,6-trimethyl-5,6-dihydro-2-pyran.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 998–1001, July, 2005. 相似文献
5.
The reaction of poly- and perfluoroaldehyde hydrazones with hydrazine hydrate was studied. A new preparative method for obtaining the hitherto inaccessibleN,N-unsubstituted bis-hydrazones of polyfluorinated -oxoaldehydes was developed based on this reaction.For Part 2, seeIzv. Akad. Nauk, Ser. Khim., 1995, 2465 [Russ. Chem. Bull, 1995,44, 2360 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2526–2527, December, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08548) and the International Science Foundation (Grant Nos. NDL 000 and NDL 300). 相似文献
6.
The asymmetric 1,2-addition of trimethylsilyl cyanide to aldehyde SAMP-hydrazones in the presence of titanium tetrachloride and diethylether in dichloromethane at −100°C up to room temperature, removal of the chiral auxiliary and acid hydrolysis affords α-amino acids in high enantiomeric excesses (ee=94-97%). 相似文献
7.
H. M. Dalloul N. S. Al-Abadla Kh. A. El-Nwairy 《Chemistry of Heterocyclic Compounds》2007,43(3):314-319
A new series of substituted 1,2,4-triazoles was synthesized from the cycloaddition reaction of alkanal and cycloalkanal hydrazones
containing electron-withdrawing groups (MeCO, PhCO, and MeOCO) with appropriate hydrazonoyl halides.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 392–398, March, 2007. 相似文献
8.
Shastin A. V. Nenajdenko V. G. Korotchenko V. N. Balenkova E. S. 《Russian Chemical Bulletin》2001,50(8):1401-1405
A new stereoselective method was developed for the synthesis of -bromostyrenes (E/Z > 5/1) starting from hydrazones of aromatic aldehydes and bromoform in the presence of CuCl. 相似文献
9.
10.
Nenaidenko V. G. Korotchenko V. N. Shast A. V. Tyur D. A. Balenkova E. S. 《Russian Chemical Bulletin》2003,52(8):1835-1840
The mechanism of formation of alkene stereoisomers in the catalytic olefination reaction of carbonyl compounds was studied. 4-Chlorobenzaldehyde hydrazone 1 stereoselectively reacts with a number of F-, Cl-, Br-, and I-containing polyhaloalkanes in the presence of catalytic amounts of CuCl to give -substituted styrenes 2 with the more thermodynamically stable alkene isomer being the major product. A model for the formation of the stereoisomers of alkenes 2 in the olefination reaction is proposed. Stereoselectivity of the reaction is determined by elimination of copper(ii) halides from the lowest-lying conformers of organocopper intermediates II. According to quantum-chemical calculations, the elimination should involve the staggered conformations with antiperiplanar arrangement of C—Hal and C—Cu bonds and proceed by the E2 anti-elimination mechanism. The results of quantum-chemical calculations are in good agreement with the experimental E/Z alkene isomer ratios. 相似文献