共查询到20条相似文献,搜索用时 31 毫秒
1.
Kaname Takagi Abdelilah Bajnati Michel Hubert-Habart 《Journal of heterocyclic chemistry》1990,27(6):1565-1568
Triacetylmethane ( 1 ) reacts with amidinohydrazines in acidic medium to afford 4-acetyl-3,5-dimethylpyrazole amidinohydrazone derivatives 2,4 . However, a similar reaction of 1 with thiosemicarbazide or semicarbazide led mainly to 3,5-dimethylpyrazole ( 6 ). The great propensity of 1 to hydrolysis accounts for this last transformation, as well as for the fact that with guanidine it led to 2-amino-4,6-dimethylpyrimidine ( 10 ) and with S-methylisothiourea it provided the unexpected 2-amino-4-methyl-6-methylthio-1,3,5-triazine ( 11 ). 相似文献
2.
Six new 4-alkynyl-2-bromoquinolines have been synthesised via palladium catalysed C? C bond formation between 2,4-dibromoquinoline and mono-substituted alkynes. Position of the alkyne substituent was confirmed to be at C-4 by an nOe experiment on some methoxy derivatives prepared by nucleophilic displacement of bromo substituent. 相似文献
3.
Avelina Arnanz Salomé Delgado Consuelo Moreno 《Journal of organometallic chemistry》2008,693(23):3457-3470
A large number of Co2(CO)6- and Co2(CO)4(L-L)-substituted alkyne complexes (L-L = dppa and dmpm) have been prepared, characterized and studied by cyclic and square-wave voltammetry. In this paper we report a comparative electrochemical study of 2,5-, 2,4-, 3,4- and 2,3-bis(trimethylsilylethynyl)thiophene dicobalt substituted alkyne complexes, in order to evaluate the extent of the electronic interaction between the “Co2C2” redox centres depending on the position of the alkynyl substituent on the thiophene ring. 相似文献
4.
V. V. Dotsenko T. Yu. Evmeshchenko N. A. Aksenov I. V. Aksenova G. D. Krapivin D. I. Sharapa F. F. Chausov V. D. Strelkov L. V. Dyadyuchenko 《Russian Journal of General Chemistry》2018,88(10):2050-2057
Aminomethylation of xanthane hydride (5-amino-1,2,4-dithiazole-3-thione) with the RNH2–HCHO system has resulted in the formation of the derivatives of new heterocyclic system (3,7-dihydro-5H-[1,2,4]-dithiazolo[4,3-a][1,3,5]triazine) in low yields. The reaction of xanthane hydride with dicyandiamide has led to thioammeline [4,6-diamino-1,3,5-triazine-2(5Н)-thione]. Some practically important properties of xanthane hydride and its derivatives have been investigated. Xanthane hydride has efficiently exhibited carbon steel corrosion in neutral aqueous media. The prepared compounds have not exhibited growth-regulating or antidote activity to herbicide 2,4-D. 相似文献
5.
It is shown that on boiling 2-amino-4,6-dimethylnicotinic acid arylamides with triethyl orthoformate in acetic anhydride, derivatives of 3-aryl-5,7-dimethyl-4-oxo-3,4-dihydropyrido[2,3-d]pyrimidine are formed. The same compounds are obtained by ternary condensation of ethyl 2-amino-4,6-dimethylnicotinate with triethyl orthoformate and alrylamines. On reaction with urea or ammonium thiocyanate, the ethyl ester or anilides of 2-amino-4,6-dimethylnicothinic acid are converted to 2,4-dioxo- or 4-oxo-2-thio-pyrido[2,3-d]pyrimidines respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1384–1386, October, 1992. 相似文献
6.
7.
G. Mekuskiene M. M. Burbuliene V. Jakubkiene E. Udrenaite P. Gaidelis P. Vainilavicius 《Chemistry of Heterocyclic Compounds》2003,39(10):1364-1368
5-(4,6-Diphenyl-2-pyrimidinyl)-1,3,4-oxadiazole-2-thione reacted with haloalkanes or their derivatives containing side chain oxo group to give S-alkylated compounds. Aminomethylation and acylation of the thione yielded N(3)-derivatives. Treatment of the title compound with hydrazine hydrate in butanol resulted in 4-amino-5-(4,6-diphenyl-2-pyrimidinyl)-1,2,4-triazole-3-thione via a recyclization reaction. Reaction of the title compound with hydrazine hydrate or phenylhydrazine in dioxane led to formation of the corresponding thiocarbohydrazides. The latter in the presence of a base were cyclized to 4-amino-1,2,4-triazole-3-thiones. 相似文献
8.
John T. Shaw Wendy L. Corbett Gregory D. Cuny Mallory F. Egler Victoria S. Peciulis 《Journal of heterocyclic chemistry》1991,28(4):987-990
The reaction of 7,9-dibromo-5-tribromornethyl-2-t-butyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 1a ) with p-toluidine is shown to give 4,6-dibromo-2-t-butyl-8,13-dihydro-13-imino-11-methyl-1,3,7,8,13c-pentaazabenzo[de]naphthacene ( 4 ) in two steps with 7,9 dibromo-2-t-butyl-4-cyano-5-p-toluidino-1,3,6,9b-tetraazaphenalene ( 2b ) as the intermediate product. A related annulation reaction of 1a with N-(5-amino-2,4-dimethylphenyl)trimethylacetamide ( 8 ) leads in two steps to 9,11-dibromo-2,13-di-t-butyl-4,6-dimethyl-7H-1,3,7,8,11b,12,14-heptaazadibenzo[de,hi]naphthacene ( 6 ) with 7,9-dibromo-2-t-butyl-4-cyano-5N-(2,4-dimethyl-5-trimethylacetamidophenyl)amino-1,3,6,9b-tetraazaphenalene ( 2d ) as the intermediate product. In a similar fashion the reaction of 1a with o-phenylenediamine forms 14-amino-4,6-dibromo-2-t-butyl-8H-1,3,7,8,13,14c-hexaazobenzo[4,5]cyclohepta[1,2-a]-phenalene ( 12 ) by way of the intermediate 5-N-(2-aminophenyl)amino-7,9-dibromo-2-t-butyl-4-cyano-1,3,6,9b-tetraazaphenalene ( 2e ). The preparation of N-(2,4-dimethyl-5-nitrophenyl)-trimethylacetamide ( 11 ) and its reduction to N-(5-amino-2,4-dimethylphenyl)trimethylacetamide ( 8 ) is also described. 相似文献
9.
By the reaction of 4-chlorobenzaldehyde with ethyl acetoacetate, malononitrile, and hydrazine hydrate, 6-amino-4-(4-chlorophenyl)-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitrile was prepared and then reacted with salicylaldehyde and CoCl2·6H2O to produce nano-Co-[4-cholorophenyl-salicylaldimine-methylpyranopyrazole]Cl2 (nano-[Co-4CSMP]Cl2). The prepared nano-Schiff base complex was reported for the first time and fully characterized by Fourier transform-infrared spectroscopy, thermal gravimetric analysis, differential thermal gravimetric analysis, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, and Brunner–Emmett–Teller analyses and applied as an efficient catalyst for the synthesis of some 1-amidoalkyl-2-naphthol derivatives. 相似文献
10.
4-Amino-5-(4,6-diphenyl-2-pyrimidinyl)-3,4-dihydro-2H-1,2,4-trazole-3-thione is formed from the reaction of 4,6-diphenylpyrimidinecarboxylic
acid or its ethyl ester with thiocarbonyl hydrazide. Alkylation of the product leads to S-alkyl derivaties or 6-substituted
3-(4,6-diphenyl-2-pyriimidinyl)-7H-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazine. Acetylation of 4-amino-5-(4,6-diphenyl-2-pyrimidinyl)-3,4-dihydro-2H-1,2,4-triazole-3-thione
gave under different conditions monoacetyl-, diacetyl, and triacetyl derivatives at the amino group and the N(2) atom, whereas benzoylation gave a benzoyl group at the amino group and 3-(4,6-diphenyl-2-pyrimidinyl)-6-phenyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, 1088–1094, July, 2007. 相似文献
11.
Yuh-Wen Ho 《中国化学会会志》1999,46(1):91-96
The reaction of 3-amino-4,6-dimethyl-2-thieno[2,3-b]pyridine carbohydrazide ( 1 ) with appropriate chalcones 2a-2d in the presence of acid catalyst produced the corresponding 3-amino-2-[(3,5-disubstituted-pyrazolin-1-yl)carbonyl]-4,6-dimethylthieno[2,3-b]pyridines 3a-3d . 3-Amino-2-[(3-substituted-pyrazolin-1-yl)carbonyl]-4,6-dimethylthieno[2,3-b]pyridines 7a, 7b were also obtained by the cyclization reaction of carbohydrazide 1 with Mannich base derivatives 6a, 6b under basic condition. 相似文献
12.
Dr. Juri Möbus Dr. Anzhela Galstyan Andreas Feldmann Dr. Constantin G. Daniliuc Dr. Roland Fröhlich Dr. Cristian A. Strassert Dr. Gerald Kehr Prof. Dr. Gerhard Erker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(37):11883-11893
In this study the scope of the 1,1‐carboboration reaction was extended to the preparation of mixed heterole‐based conjugated π‐systems. Two arylbis(alkynyl)phosphane starting materials 2 were synthesized bearing two thiophene isomers at the alkyne units and the bulky tipp‐substituent (tipp=2,4,6‐triisopropylphenyl) at the phosphorous atom. The bis(thienylethynyl)phosphanes 2 were converted into the corresponding 2,5‐thienyl‐substituted 3‐borylphospholes 4 in a double 1,1‐carboboration reaction sequence employing the strongly electrophilic B(C6F5)3 reagent under mild reaction conditions. Subsequent Suzuki–Miyaura type cross‐coupling yielded the corresponding 3‐phenylphospholes 7 in a one‐pot procedure from phosphanes 2 in high yields. Phospholes 7 were converted into the respective phosphole oxides 8 . A photophysical characterization of derivatives 7 and 8 was carried out. The results presented here demonstrate the suitability of the 1,1‐carboboration reaction for the preparation of phosphole‐/thiophene‐based, light‐emitting systems. 相似文献
13.
V RaghukumarD Thirumalai V.T Ramakrishnan V KarunakaraP Ramamurthy 《Tetrahedron》2003,59(21):3761-3768
4,6-Diaryl-2-(pyrrolidin-1-yl)-nicotinonitriles 2a-k and 3-amino-2,4-dicyano-5-aryl-biphenyls 3a-c were synthesized from 1,3-diaryl-prop-2-en-1-ones 1a-k and malononitrile by a convenient one-pot method. Likewise, the reaction of aromatic aldehydes with malononitrile afforded 6-amino-4-aryl-2-(pyrrolidin-1-yl)-pyridine-3,5-dicarbonitriles 6a-f. The reaction of mesityl oxide with malononitrile gave 5-amino-7-(pyrrolidin-1-yl)-2,4,4-trimethyl-1,4-dihydro-1,6-naphthyridine-8-carbonitrile 8. The NLO studies of the pyridinedinitrile derivatives 6a, b, f showed a high value while that of nicotinonitrile 2b was weak. 相似文献
14.
Buryi D. S. Dotsenko V. V. Aksenov N. A. Aksenova I. V. Krivokolysko S. G. Dyadyuchenko L. V. 《Russian Journal of General Chemistry》2019,89(8):1575-1585
The reaction of 3-pentylpentane-2,4-dione with cyanothioacetamide afforded 4,6-dimethyl-5-pentyl-2-thioxo-1,2-dihydropyridine-3-carbonitrile. Alkylation of the latter led to the formation of 2-alkylsulfanyl-4,6-dimethyl-5-pentylpyridine-3-carbonitriles or 3-amino-4,6-dimethyl-5-pentylthieno[2,3-b]pyridines, depending on the alkylating agent and reaction conditions. The structures of the key compounds were proved by 2D NMR spectroscopy and X-ray analysis. Biological activity of the synthesized compounds was evaluated in silico. Some compounds were experimentally found to stimulate growth of sunflower seedlings.
相似文献15.
Lei Zhou Qi Shuai Huan‐feng Jiang Chao‐Jun Li Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(43):11668-11674
A simple and efficient method for the synthesis of γ,δ‐alkynyl‐β‐amino acid derivatives by a copper‐catalyzed three‐component amine–alkyne–alkyne addition reaction was developed. Various γ,δ‐alkynyl‐β‐amino acid derivatives were synthesized in moderate to good yields in one step. With chiral prolinol derivatives employed as the amine component, excellent diastereoselectivities (up to >99:1 diastereomeric ratio (dr)) were obtained. The scope of the reaction and further transformations of the resulting amino acid derivatives, such as deprotection and cyclization are also described. 相似文献
16.
3,5-Di(hydroxyalkyl) derivatives of 4-amino-1,2,4-triazole and the corresponding derivatives of 1,2,4-triazole obtained by diazotizing them are converted by reaction with SOCl2 into the hydrochlorides of 4-amino-3,5-di(chloroalkyl)-1,2,4-triazoles and 3,5-di(chloroalkyl)-1, 2,4-triazoles. The dinitrate of 3,5-di(hydroxymethyl)-1,2,4-triazole has been prepared. When the cyanohydrazide of glycolic acid is heated with hydrazine hydrate, 4,5-diamino-3-hydroxymethyl-1, 2,4-triazole is formed. 相似文献
17.
Shahnaz Rostamizadeh Masoomeh Nojavan Reza Aryan Hamid Sadeghian Mahdieh Davoodnejad 《中国化学快报》2013,24(7):629-632
In this work 4-amino-6-aryl-2-phenyl pyrimidine-5-carbonitrile derivatives were synthesized through a one-pot,three-component reaction of an aldehyde,malononitrile and benzamidine hydrochloride,in the presence of magnetic nano Fe3O4 particles as a catalyst under solvent-free conditions.3-Amino-6-aryl- 2-phenylpyrazolo[3,4-d]pyrimidine derivatives were prepared through an efficient and environmentally friendly reaction between 4-amino-6-aryl-2-phenylpyrimidine-5-carbonitrile derivatives and hydrazine hydrate and their antibacterial activity has been evaluated. 相似文献
18.
《合成通讯》2013,43(24):4229-4234
Abstract Two novel methods for synthesis of nicotinic acid derivatives with unsymmetrical substitution patterns were presented via ketene dithioacetals. The ketene N,S-acetals 2 reacted with β-ketoesters or β-cyanoesters to give 4-amino-5-cyano-2-alkyl-6-methylthio-nicotinic acid derivatives 3 or 2,4-diamino-5-cyano-6-methylthio-nicotinic acid ethyl ester 4. However, 6-amino-5-cyano-2-alkyl-4-methylthio-nicotinic acid esters 6 were obtained by the reaction of the ketene dithioacetals 1 and β-amino-crotonates. 相似文献
19.
V. K. Voronov B. A. Trofimov G. M. Gavrilova S. V. Amosova V. I. Gostevskaya 《Chemistry of Heterocyclic Compounds》1981,17(4):347-349
An analysis of the PMR spectra of 2H, 6H-2, 6-dimethyl-4-amino-1,3,5-dithiazine, its acyl derivatives, and 2H, 3H, 6H-2, 6-dimethyl-4-amino-1,3,5-thiadiazine in various solvents and in the presence of Eu(FOD)3 [tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimettyl-4,6-octanedionato)3 europium] confirms the structure assigned to it and makes it possible to prefer a cis orientation of the methyl substituents in the half-chair conformation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 485–487, April, 1981. 相似文献
20.
Gold(III) Chloride Catalyzed Synthesis of Chiral Substituted 3‐Formyl Furans from Carbohydrates: Application in the Synthesis of 1,5‐Dicarbonyl Derivatives and Furo[3,2‐c]pyridine
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Kanchan Mal Abhinandan Sharma Dr. Indrajit Das 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(37):11932-11945
This report describes a gold(III)‐catalyzed efficient general route to densely substituted chiral 3‐formyl furans under extremely mild conditions from suitably protected 5‐(1‐alkynyl)‐2,3‐dihydropyran‐4‐one using H2O as a nucleophile. The reaction proceeds through the initial formation of an activated alkyne–gold(III) complex intermediate, followed by either a domino nucleophilic attack/anti‐endo‐dig cyclization, or the formation of a cyclic oxonium ion with subsequent attack by H2O. To confirm the proposed mechanistic pathway, we employed MeOH as a nucleophile instead of H2O to result in a substituted furo[3,2‐c]pyran derivative, as anticipated. The similar furo[3,2‐c]pyran skeleton with a hybrid carbohydrate–furan derivative has also been achieved through pyridinium dichromate (PDC) oxidation of a substituted chiral 3‐formyl furan. The corresponding protected 5‐(1‐alkynyl)‐2,3‐dihydropyran‐4‐one can be synthesized from the monosaccharides (both hexoses and pentose) following oxidation, iodination, and Sonogashira coupling sequences. Furthermore, to demonstrate the potentiality of chiral 3‐formyl furan derivatives, a TiBr4‐catalyzed reaction of these derivatives has been shown to offer efficient access to 1,5‐dicarbonyl compounds, which on treatment with NH4OAc in slightly acidic conditions afforded substituted furo[3,2‐c]pyridine. 相似文献