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1.
Syntheses of 2,5-bis(4-methyl-2-thienyl)thiophene 3 and 2,5-bis(4-methyl-2-thienyl)pyrrole 4 are described. The key step involves Stetter reaction between 4-methyl-2-thiophenecarboxaldehyde and divinyl sulfone. Cyclizaton of the resulting 1,4-bis-(4-methyl-2-thienyl)-1,4-butanedione 2 with Lawesson's reagent gives 2,5-bis(4-methyl-2-thienyl)thiophene 3, whereas condensation with ammonium acetate provides the 2,5-bis(4-methyl-2-thienyl)pyrrole 4. 相似文献
2.
2, 5-Dimethyl-4-styrylpyridine and 2,5-dimethyl-4-phenylethynylpyridine are prepared from 2, 5-dimethyl-4-β-phenylethylpyridine. Hydration of the second of these compounds gives gw-(2,5-dimethylpyridyl-4)acetophenone. 相似文献
3.
The reactions of 1-aryl-4-hydrazinocarbonyl-2-pyrrolidinones with 2,4-pentanedione and 2,5-hexanedione have been studied.
It was found that heating the hydrazinocarbonyl compounds with 2,4-pentanedione gave 3,5-dimethylpyrazole compounds and with
2,5-hexanedione gave 1-substituted 2,5-dimethylpyrroles.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 229–232, February, 2008. 相似文献
4.
A. G. Mal''kina V. V. Nosyreva R. N. Kudyakova L. V. Sokolyanskaya B. A. Trofimov 《Russian Journal of Organic Chemistry》2001,37(5):649-654
The reaction of 4-alkyl-4-hydroxy-2-alkynenitriles with hydrogen halides (HCl and HI) in dioxane is accompanied by intramolecular cyclization with formation of 5,5-dialkyl-4-halo-2-imino-2,5-dihydrofuran hydrohalides. Treatment of the latter with K2CO3 in ethanol yields 5,5-dialkyl-4-halo-2-imino-2,5-dihydrofurans. 相似文献
5.
Synthesis of 2-imino-4-vinyl-2,5-dihydrofuran-3-carboxamides and some their chemical transformations
A. A. Avetisyan L. V. Karapetyan M. D. Tadevosyan 《Russian Journal of Organic Chemistry》2009,45(7):1031-1035
2-Imino-2,5-dihydrofuran-3-carboxamides containing 2-phenyl- and 2-furylvinyl substituents in position 4 of the furan ring were synthesized by condensation of 2-imino-4-methyl-2,5-dihydrofuran-3-carboxamides with the corresponding aldehydes. Acid hydrolysis of 4-(2-arylvinyl)-2-imino-2,5-dihydrofuran-3-carboxamides gave 4-(2-arylvinyl)-2-oxo-2,5-dihydrofuran-3-carboxamides, and their condensation with malononitrile resulted in the formation of 2-dicyanomethylidene derivatives. 相似文献
6.
《合成通讯》2012,42(24):3401-3411
AbstractThe base-catalyzed reaction of 1,5-diphenyl-pentane-1,3,5-trione with aromatic/heteroaromatic 1,2-diones leading to the synthesis of 2,5-diaroyl-4-hydroxycyclopent-2-enones and its conversion to 2,5-diaroylcyclopentadienones is reported here. 2,5-Dibenzoyl-4-hydroxycyclopent-2-enone and 2,5-dithenoyl-4-hydroxycyclopent-2-enone are valuable compounds which act as chemosensors for selective detection of Fe3+ and Cu2+, respectively. 相似文献
7.
Reaction between the title compounds gave the unexpected 3-[5,5-dimethyl-2,5-dihydrofur-4-yl-2-(3-isopropanol-2-propenonitrile)imino]benzothiazol-2-one, as a result of the addition of two cyanoacetylene molecules.Irkutsk Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, Irkutsk 664033. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 4, pp. 1003–1005, April, 1992. 相似文献
8.
Gas-phase eliminations of 4-substituted-2-alkoxythiazoline-5-ones have been studied. These compounds eliminate via a six-membered transition state to produce 4-substituted-thiazolidine-2,5-diones. These eliminations are unimolecular first-order reactions. Utilization of this thermolysis reaction in the synthesis of new 4-substituted-thiazolidine-2,5-diones is considered. Additional mechanistic information was obtained by comparing the kinetic data for thermal elimination reactions of these compounds with that of 1-ethoxythiazole. © 1996 John Wiley & Sons, Inc. 相似文献
9.
A. Sh. Sharifkanov Sh. S. Akhmedova R. A. Timirova I. S. Chanysheva E. G. Il' yasov 《Chemistry of Heterocyclic Compounds》1971,7(3):326-327
1,4-Bis(2,5-dimethyl-4-hydroxypiperidino)-2-butene and 1,4-bis(2,5-dimethyl-4-hydroxypiperidino)-2-butyne (II and III) were obtained by the action of 1,4-dibromo-2-butene and 1,4-dibromo-2-butyne on the form of 2,5-dimethyl-4-piperidol (I). The benzoates (IV and V) were obtained by acylation of II and III with benzoyl chloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 352–353, March, 1971. 相似文献
10.
A. Sh. Sharifkanov K. Kh. Tokmurzin R. B. Atshabarova 《Chemistry of Heterocyclic Compounds》1969,5(4):555-556
They -isomers of 1-(3-chlorobuten-2-yl)- and 1-benzyl-2,5-dimethyl-4-ethynylpiperid-4-ols (I, II) and of 1-(3-chlorobuten-2-yl)-2,5-diemethyl-4-vinylpiperid-4-ol (III) and the quaternary salts of compounds I–III and of the -isomers of the 1,2,5-trimethyl-4-ethynyl-(vinyl)piperid-4-ols [1] have been synthesized. 相似文献
11.
Oxidation of 2-formyl-4-methoxyphenol with thallium trinitrate in methanol and trimethylorthoformate gives 2-dimethoxymethyl-4,4-dimethoxycyclohexa-2,5-dienone whereas oxidation of 2-methoxycarbonyl-4-methoxyphenol gives 2-methoxycarbonyl-3,4,4-trimethoxycyclohexa-2-5-dienone. 相似文献
12.
K. Kh. Tokmurzin A. Sh. Sharifkanov S. Shyntasova T. Kenzhegalieva 《Chemistry of Heterocyclic Compounds》1975,11(8):965-966
2-Vinylpyridine adds to 2,5-dimethyl-4-piperidone in the 1 position in the presence of acetic acid and in the 5 position in the presence of sodium metal. 相似文献
13.
The reaction of 1,2-ethanediol with 4-hydroxy-4-methyl-2-pentynonitrile in the presence of a catalytic amount of metallic sodium or triethylamine leads to 2,5-dihydro-5,5-dimethyl-2-imino-4-(2-hydroxyethoxy)furan.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1671–1673, July, 1991. 相似文献
14.
Organolithium react with 5-ethoxy 2,5 dihydro-furan-2-one , easily obtained by photoxidation of furfural, leading selectively to 5-hydroxy-2,5-dihydro-furans or to 5-ethoxy-2,5 dihydro-furans disubstituted on carbon 4 ; the odcydation of the hemi-acetals transforms them with good yields in 3-2 butenolides disubstituted on carbon 4. 相似文献
15.
16.
Rajab Abu-El-Halawa Alaa Sarabi Mustafa M. El-Abadelah 《Monatshefte für Chemie / Chemical Monthly》2008,44(8):1251-1255
Interaction between 2,5-dichlorothiophene-3-carbonyl isothiocyanate, accessible via 2,5-dichlorothiophene-3-carbonyl chloride, and model heterocyclic amines produced the respective 2,5-dichloro-N-(substituted aminocarbonothioyl)thiophene-3-carboxamides. Upon heating, the deprotonated form of the latter underwent intramolecular
cyclization to deliver the corresponding 2-(substituted amino)-4H-thieno[3,2-e]-1,3-thiazin-4-ones. The structures of these new bicyclic derivatives and their acyclic precursors are based on microanalytical
and spectral (IR, MS, and NMR) data. 相似文献
17.
A. D. Dubonosov S. V. Galichev V. A. Chernoivanov V. A. Bren' V. I. Minkin 《Russian Journal of Organic Chemistry》2001,37(1):67-71
3-(4-Nitrophenyl)bicyclo[2.2.1]hepta-2,5-diene-2-carbaldehyde and its derivatives at the formyl group were synthesized. By reduction of the nitro group the corresponding 3-(4-aminophenyl)-substituted compounds were obtained, as well as 4,4'-bis(bicyclo[2.2.1]hepta-2,5-dien-2-yl)azobenzenes. Irradiation of the resulting norbornadiene derivatives in the region of their absorption maxima resulted in valence isomerization with formation of the corresponding quadricyclanes. The reverse transformations are promoted by molybdenum(VI) oxide as heterogeneous catalyst. 4,4'-Bis(bicyclo[2.2.1]hepta-2,5-dien-2-yl)azobenzenes undergo reversible (on heating) photochemical EZ/ isomerization at the NÍN bond. 相似文献
18.
A. A. Moiseeva G. V. Gavrilova E. K. Beloglazkina D. M. Krut’ko N. V. Zyk 《Russian Journal of General Chemistry》2011,81(8):1658-1663
Electrochemical investigation of 4(6)-dihalomethyl-4(6)-methylcyclohexa-2,5(2,4)-dien-1-ones using cyclic voltammetry (CVA)
and rotating disc electrode (RDE) methods has been performed. The reductive dehalogenation of cyclohexa-2,5(2,4)-dien-1-ones
having a dihalomethyl substituent at the tertiary carbon atom was shown to proceed as a two-electron reductive elimination
of the geminal halogen atoms with the intermediate formation of carbene and subsequent rearrangement of cyclohexadienone with
the ring expansion to the corresponding 4- or 2-methylcyclohepta-2,4,6-trien-1-one. 相似文献
19.
4-羰基-2-戊烯醛与硫代乙酸加成的研究 总被引:1,自引:1,他引:0
以2-甲基-2,5-二甲氧基-2,5-二氢呋喃水解产物与硫代乙酸加成并在不同条件下关环,制得了β-乙酰硫基呋喃、噻吩和毗咯的各种异构产物,提供了按需要制备不同α-甲基-β-巯基呋喃、噻吩和吡咯衍生物的途径。 相似文献
20.
Joseph G. Lombardino 《Journal of heterocyclic chemistry》1973,10(5):697-698
Several 2-aryl-4-phenyl-5-trifluoromethylimidazoles have been made from the previously unknown 1-phenyl-3,3,3-trifluoro-1,2-propanedione monohdyrate. One analog, 4-phenyl-2,5-bis(trifluoromethyl)imidazole, is quite acidic, exhibiting pKa 8.1. 相似文献