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1.
Rolf Carlson Alexandre Descomps Alemayehu Mekonnen Andreas Westerlund Martina Havelkova 《合成通讯》2013,43(19):2939-2945
A convenient procedure for the synthesis of 1-bromo-3-buten-2-one, 4, from commercially available 2-ethyl-2-methyl-1,3-dioxolane, 1, is described. The procedure involves three reaction steps: (1) The acetal 1 is converted to 2-(1-bromoethyl)-2-bromomethyl-1,3-dioxolane, 2, by reacting 1 with elemental bromine in dichloromethane to yield 98% of 2. (2) Dehydrobromination of 2 with potassium tert-butoxide in tetrahydrofuran gives 2-bromomethyl-2-vinyl-1,3-dioxolane, 3, in 84–93% yield. (3) Removal of the acetal protection from 3 by formolysis for 6–10 h afforded 1-bromo-3-buten-2-one, 4, in 85–94% yield. A more rapid method is acid hydrolysis of 3 under microwave activation (100 °C, 8–10 min), by which 4 was obtained in 75% yield. Full experimental details are given.
2.
Alexandre Descomps 《合成通讯》2014,44(6):757-761
The unstable ketones 1-bromo-3-buten-2-one, 1-bromo-3-butyn-2-one, and 1,3-dibromo-3-buten-2-one can be obtained from the corresponding acetals in high yields by treating the acetals with anhydrous iron (III) chloride suspended on dry silica. A simplified procedure for preparing the reagent is also given. 相似文献
3.
L. M. Potikha A. R. Turelyk V. A. Kovtunenko A. V. Turov G. V. Palamarchuk R. I. Zubatyuk O. V. Shishkin 《Chemistry of Heterocyclic Compounds》2010,46(6):742-753
(Z)-4-Bromo-1,3-di(2-thienyl)-2-buten-1-one was obtained by the bromination of 1,3-di(2-thienyl)-2-buten-1-one by NBS in anhydrous
CCl4. The starting butanone was obtained by the condensation of 1-(2-thienyl)-1-ethanone by the action of SOCl2. The reaction of (Z)-4-bromo-1,3-di(2-thienyl)-2-buten-1-one with tertiary amines such as Et3N, pyridine, 1-alkyl-1,3-diazole, 1-alkylbenzimidazole, and 1-alkyl-1,2,4-triazole leads to quaternary salts. The azolium
salts cyclize by the action of base to give di(2-thienyl)azolo[a]pyridinium derivatives. 3-Methyl-6,8-di(2-thienyl)[1,3]thiazolo[3,2-a]pyridin-4-ium
and 2,4-di(2-thienyl)pyrido[2,1-b]benzothiazol-10-ium bromides were obtained by the same procedure but without separating
the intermediate quaternary salts. 相似文献
4.
L. M. Potikha A. R. Turelik V. A. Kovtunenko 《Chemistry of Heterocyclic Compounds》2009,45(10):1184-1189
Bromination of 1,3-bis(aryl)-2-buten-1-ones by N-bromosuccinimide in anhydrous carbon tetrachloride gives Z-1,3-bis(aryl)-4-bromo-2-buten-1-ones.
The effect of the nature of substituent in the benzene ring on the course of a reaction with nucleophiles has been studied.
Heating an alcohol solution of these ketones (Ar = 4-MeOC6H4, 4-ClC6H4) in the presence of acid or in the presence of base (Ar = Ph) gave 2,4-bis(aryl)furans. Treatment of 1,3-bis(aryl)-4-bromo-2-buten-1-ones
with thioacetamide gave 2,4-bis(aryl)thiophenes. The oxidation of the halo-substituted dypnones with H2O2/NaOH gave (3-bromomethyl-3-aryl-2-oxiranyl)(aryl)methanones. The reaction of halo-substituted dypnones with aryl hydrazines
gave 1,3,5-triaryl-1,6-dihydropyridazines or 1,3,5-triarylpyridazinium bromides depending on the structure of the reagents. 相似文献
5.
Timothy B. Patrick Titus Y. Agboka Keith Gorrell 《Journal of fluorine chemistry》2008,129(10):983-985
3-Fluoro-3-buten-2-one (2) is readily prepared from 1-fluoro-1-chloro-2-methoxy-2-methylcyclopropane (1) in 82% yield by heating the cyclopropane in aqueous quinoline solution. Ketone 2 reacts with aryl iodides (3) in a Heck reaction catalyzed by Pd(OAc)2 to give Z-3-fluorobenzalacetones (4) in 36-86% yield. 相似文献
6.
The reaction of 4-bromo-1,3-diphenyl-2-buten-1-one with thiourea or N,N′-diphenylthiourea gives 2-(2-amino-4-phenyl-4,5-dihydro-1,3-thiazol-4-yl)-and
2-[3,4-diphenyl-2-(phenylimino)-1,3-thiazolidin-4-yl]-1-phenyl-1-ethanone — the products of nucleophilic substitution of the
halogen atom and Michael addition at position 3 of the 2-buten-1-one system. A similar reaction with thiosemicarbazide and
1-phenylthiosemicarbazide gives the 4-(2-oxo-2-phenylethyl)-4-phenyl-and 4-(2-oxo-2-phenylethyl)-3,4-diphenyl-1,3-thiazolidin-2-one
hydrobromides respectively.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 103–110, January, 2008. 相似文献
7.
Koval'skaya S. S. Kozlov N. G. Dikusar E. A. 《Russian Journal of Organic Chemistry》2004,40(5):668-674
Reaction of 2-(3-hydroxy-3-methyl-1-butynyl)adamantan-2-ol with acetonitrile under Ritter reaction conditions is accompanied by isomerization and partial hydration where the water addition to the triple bond occurs nonselectively. As a result of reaction carried out in the presence of 8 equiv of sulfuric acid a mixture was obtained of N
2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]-acetamide, and N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-1-oxo-3-butyl]acetamide in ~10:3:2 ratio. In the presence of 2 equiv of the acid the mixture obtained consisted of N
2-[4-(1-acetylamino-2-adamantyl)-2-methyl-3-butyn-2-yl]acetamide, N
3-[1-(1-acetylamino-2-adamantyl)-3-methyl-2-oxo-3-butyl]acetamide, and 1-(1-acetylamino-2-adamantyl)-3-methyl-2-buten-1-one in the same ratio. In Rupe reaction conditions we obtained instead of the expected ,-unsaturated ketones a mixture of 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-1-one and 1-(1-hydroxy-2-adamantyl)-3-hydroxy-3-methylbutan-2-one in a 5:3 ratio. 相似文献
8.
Rulev A. Yu. Fedorov S. V. Chuvashev Yu. A. Voronkov M. G. 《Russian Journal of Organic Chemistry》2003,39(5):646-649
Piperidine reacts with 3-bromo-3-buten-2-one to give a mixture of 3,4-dipiperidinobutan-2-one and 3-piperidino-3-buten-2-one. The latter is also formed by the action of a strong base (Et3N in THF or MeONa in MeOH) on the dipiperidino derivative. Analogous reaction of 2-bromo-3-phenylpropenal with N-methylaniline affords 2-[methyl(phenyl)amino]-3-phenylpropenal which is the first captodative formyl(amino)alkene having a weakly basic tertiary amino group. 相似文献
9.
10.
John F. Hansen John A. Easter David A. Eckert Karen J. Hunt David A. Little 《Journal of heterocyclic chemistry》1994,31(2):281-286
Nitrosation of the oximes of 3-bromo-3-penten-2-one, 3-bromo-4-phenyl-3-buten-2-one, and 2-bromo-1,3-diphenyl-2-propen-1-one using sodium nitrite in acetic acid gave low yields of 4-pyrazolone 1,2-dioxides. Nitrosation using butyl nitrite in the presence of copper(II) sulfate and pyridine in aqueous ethanol produced insoluble copper complexes from which 3,5-dimethyl-, 3-methyl-5-phenyl-, and 3,5-diphenyl-4-bromo-1-hydroxypyrazole 2-oxides could be liberated by treatment with dilute potassium hydroxide, filtration, and acidification of the filtrate. High yields were obtained with the first two oximes, but, presumably due to unfavorable stereochemistry of the oxime, the diphenyl derivative gave a lower yield of the complex, accompanied by 4-bromo- and 4-nitro-3,5-diphenylisoxazole and 4-oximino-3,5-diphenyl-4,5-dihydroisoxazole. 相似文献
11.
Liwei Cao Charles U. Pittman 《Journal of polymer science. Part A, Polymer chemistry》1999,37(15):2823-2840
Carbon black-supported sulfuric acid or BF3·Et2O-initiated polymerizations of 2-methylene-4,4,5,5-tetramethyl-1,3-dioxolane (1), 2-methylene-4-phenyl-1,3-dioxolane (2), and 2-methylene-4-isopropyl-5,5-dimethyl-1,3-dioxane (3) were performed. 1,2-Vinyl addition homopolymers of 1–3 were produced using carbon black-supported H2SO4 initiation at temperatures from 0°C to 60°C whereas both ring-opened and 1,2-vinyl structural units were present in the polymers using BF3·Et2O as an initiator. Cationic polymerizations of 2-methylene-1,3-dithiolane (4) and copolymerization of 4 with 2-methylene-4-(t-butyl)-1,3-dioxolane (5) were initiated with either carbon black-sulfuric acid or BF3·Et2O. Insoluble 1,2-vinyl addition homopolymers of 4 were obtained upon initiation with the supported acid or BF3·Et2O. A soluble copolymer of 2-methylene-1,3-dithiolane (4) and 4-(t-butyl)-2-methylene-1,3-dioxolane (5) was obtained upon BF3·Et2O initiation. This copolymer is composed of three structural units: a ring-opened dithioester unit, a 1,2-vinyl-polymerized 1,3-dithiolane unit, and a 1,2-vinyl polymerized 4-(t-butyl)-1,3-dioxolane unit. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2823–2840, 1999 相似文献
12.
Roger Martin Christopher B. Chapleo Karen L. Svanholt Andr S. Dreiding 《Helvetica chimica acta》1976,59(8):2724-2727
Synthesis of Bromosubstituted Butenolides II . Methyl 4,4′-dibromosenecioate ( 2 ) was prepared by double N-bromosuccinimide bromination of methyl senecioate ( 1 ) and converted to methyl 4,4′-diiodo-senecioate ( 3 ) with sodium iodide and to 3-bromomethyl-2-buten-4-olide ( 4 ) with aqueous hydrobromic acid. A mixture of methyl (Z)- and (E)-4-bromosenecioate ( 8 and 9 ) yielded 3-methyl-2-butenolide ( 5 ) with aqueous hydrobromic acid and a mixture of (Z)-and (E)-4-methoxy-senecioic acid ( 10 and 11 ) with methanolic potassium hydroxide. N-Bromosuccinimide treatment of the butenolide 5 afforded 4-bromo-3-methyl-2-buten-4-olide ( 6 ) and 4,4-dibromo-3-methyl-2-buten-4-olide ( 7 ). 相似文献
13.
The hydroxyacetylpiperidines, their ethylene ketals, and the N-benzyl derivatives of these new piperidines have been synthesized. Methylolation of 2-(2- and 4-pyridyl)-1,3-dioxolanes by heating with paraformaldehyde at 185° led to 2-hydroxymethyl-2-(2- and 4-pyridyl)-i,3-dioxolanes ( 7,8 , respectively). 2-Hydroxymethyl-2-(3-pyridyl)-1,3-dioxolane ( 13 ) was obtained by reaction of 2-bromomethyl-2-(3-pyridyl)-1,3-dioxolane with aqueous sodium hydroxide at 190°. Hydrogenation of these pyridine ketals with rhodium-charcoal catalyst produced the corresponding piperidine ketals (16,17,18). Acid hydrolysis of the piperidine ketals and their N-benzyl derivatives led to the hydroxyacetylpiperidines (1,2,3) and their N-benzyl derivatives (25,26,27). The N-benzylhydroxyacetylpiperidines undergo rapid hydrogenolysis with palladium-charcoal catalyst to produce the hydroxyacetylpiperidines. Further hydrogenation produces the piperidyl-1,2-ethanediols. The hydroxyacetylpiperidines are somewhat unstable, hygroscopic substances which polymerize with dehydration on standing; in solution they are relatively stable. Their N-benzyl, ketal, and hydrochloride salt derivatives, on the other hand, represent stable, synthetically useful intermediates from which the reactive trifunctional hydroxyacetylpiperidines may readily be prepared. 相似文献
14.
Felipa M. Bautista Juan M. Campelo Angel Garcia Raquel M. Leon Diego Luna Jose M. Marinas Antonio A. Romero 《Reaction Kinetics and Catalysis Letters》1998,65(2):239-244
2-Methyl-3-butyn-2-ol underwent almost exclusively dehydration to 3-methyl-3-buten-1-yne (acid activity) on pure AlPO4, whereas its modification with cesium oxide developed AlPO4-based materials with increased basic properties and hence, high selectivities to the base-catalyzed cleavage of MBOH yielding
acetone and acetylene. At the same conversion level, catalysts obtained from cesium chloride exhibit higher selectivities
to the base-catalyzed process than those obtained from cesium acetate. 相似文献
15.
4-[2-cyclopentenyl]-3-hydroxy [1] bonzopyran-2-one(3) was cyclised to the bicyclie coumar in-1,3-ethano-2-bromo-1,2-dihydro-3H-pyrano [2,3-c] [1] benzopyran-5-one (6) by a sequence of reactions viz. acetylation of 3, addition of bromine to cyclopenteny double bond and treating the resulting acetyldibromo compound (5) with 4% alcoholic KOH, Cyclisation of compound (3) with mercuric acetate in methanol gave condensed furan derivative 7 which on reductive demercuration with zinc borohydride in dimethoxyethane gave the 1,3-propano-1,2-dihydrofuro [2,3-c] [1] benzopyran-4-one, 8. Cyclisation of compound 2 with come. H2SO4 furnished a mixture of bicyclic derivative 9 ad furo coumarin derivative 8. 相似文献
16.
L. G. Shagun I. A. Dorofeev I. A. Mikhailova V. A. Shagun M. G. Voronkov 《Chemistry of Heterocyclic Compounds》2006,42(11):1478-1481
The reaction of 8-mercaptoquinolinium bromide with 1,3-dibromopropane-2-thione or 3,3-dibromobutane-2-thione in methanol gave
the 2-bromomethyl-2-mercaptotetrahydro-1,4-thiazino[2,3,3,4-i,j]quinolinium and 3-bromo-2-mercapto-2,3-dimethyltetrahydro-1,4-thiazino[2,3,3,4-i,j]quinolinium
bromides which readily exchanged the Br− anion for ClO
4
−
upon treatment with sodium perchlorate in methanol. Oxidation of the 3-bromo-2-mercapto-2,3-dimethyltetrahydro-1,4-thiazino[2,3,3,4-i,j]-quinolinium
bromide by selenium dioxide gave 2,2-dithiobis(3-bromo-2,3-dimethyltetrahydro-1,4-thiazino[2,3,3,4-i,j]quinolinium) bromide.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1720–1723, November, 2006. 相似文献
17.
Jignesh P. Raval Krunal G. Desai Kishor R. Desai 《Journal of Saudi Chemical Society》2012,16(4):387-393
Heterocyclic compounds containing pyrazolyl-oxopropyl-quinazolin-4(3H)-one are reported to possess significant biological activity. Syntheses of 6-bromo-2-(3-chloro-2-oxopropyl)-3-(4-fluorophenyl)quinazolin-4(3H)-one 2 6-bromo-3-(4-fluorophenyl)-2-(3-hydrazinyl-2-oxopropyl)quinazolin-4(3H)-one 3 and 6-bromo-2-(3-(3-(4-(1-(2-chlorophenyl)-3-methyl-1H-pyrazol-5(4H)-ylideneamino)phenyl)-5-(substituted phenyl)-4,5-dihydro-1H-pyrazol-1-yl)-2-oxopropyl)-3-(4-fluorophenyl)quinazolin-4(3H)-one 5a–j using microwave irradiation have been described. These compounds have been characterized on the basis of the UV, IR, 1H NMR, 13C NMR, Mass and elemental analysis. Compounds have been evaluated for their antimicrobial activity. 相似文献
18.
L. M. Potikha V. A. Kovtunenko A. V. Turov G. V. Palamarchuk R. I. Zubatyuk O. V. Shishkin 《Chemistry of Heterocyclic Compounds》2009,45(3):327-335
The direction of the reaction of 4-bromo-1,3-diphenyl-2-buten-1-one (γ-bromodypnone) with hydrazines depends on the nature
of the substituent they contain. Reaction with 1-methylhydrazinium hydrosulfate gives 1-methyl-3,5-diphenylpyridazin-1-ium
bromide but carboxylic acid hydrazides give N-(2,4-diphenyl-1H-pyrrol-1-yl)carboxylic acid amides. γ-Bromodypnone and phenylhydrazine
give both 1,3,5-triphenyl-1,4-dihydropyridazine and N,2,4-triphenyl-1H-pyrrol-1-amine (15%). 1-(2,4-Dinitrophenyl)hydrazine
gives the 2,4-dinitrophenylhydrazone of (Z)-4-bromo-1,3-diphenyl-2-buten-1-one. Condensation of 2,4-diphenyl-1H-pyrrol-1-amine
with aromatic aldehydes readily leads to N-(arylmethylidene)-2,4-diphenyl-1H-pyrrol-1-amines and alkylation with methyl iodide
gives N,N-dimethyl-2,4-diphenyl-1H-pyrrol-1-amine.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–414, March, 2009. 相似文献
19.
V. V. Shchepin A. E. Korzun M. I. Vakhrin P. S. Silaichev M. A. Ezhikova M. I. Kodess 《Russian Journal of Organic Chemistry》2006,42(9):1344-1347
3-Aroyl-6-bromochromen-2-ones and 2-benzoylbenzo[f]chromen-3-one reacted with zinc enolates derived from 1-aryl-2-bromoalkanones and 1-aryl-2-bromo-2-phenylethanone to give, respectively, 4-(1-alkyl-2-aryl-2-oxoethyl)-3-aroyl-6-bromochroman-2-ones and 1-(2-aroyl-1-methyl-2-oxoethyl)-2-benzoyl-1,2-dihydrobenzo[f]chromen-3-ones as a single stereoisomer. Treatment with acetic anhydride of the intermediate product obtained from 3-benzoyl-6-bromochromen-2-one and [1-(4-chlorophenyl)-2-phenylethen-1-yloxy]-zinc(II) bromide resulted in the formation of 3-(1-acetoxy-1-phenylmethylidene)-6-bromo-4-[2-(4-chlorophenyl)-2-oxo-1-phenylethyl]chroman-2-one. 相似文献
20.
Michael J. Blandamer John Burgess Stephen J. Hamshere Fikry M. Mekhail 《Transition Metal Chemistry》1979,4(2):77-81
Summary Rate constants are reported and discussed for several substitutions of inorganic complexes in ethylene carbonate (1,3-dioxolan-2-one) + water and in propylene carbonate (4-methyl-1,3-dioxolan-2-one) + water solvent mixtures. The reactions include aquation ofcis- and oftrans-[Co(en)2Cl2]+, aquation oftrans-[Cr(OH2)4Cl2]+, bromide substitution at [Pd(Et4dien)Cl]+, thiourea substitution atcis-[Pt(4-NCpy)2Cl2], and aquation and cyanide attack at [Fe(X-phen)3]2+ cations. 相似文献