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1.
The reactions of the 2,3‐dihydro‐1H‐furan‐2,3‐dione 1 with Schiff bases 2a‐f at 60–70°C furnish the corresponding 2,3‐dihydro‐1H‐pyrole‐2,3‐diones 3a‐f . The heating of 3a‐d afforded the corresponding 4‐methoxybenzoyl(N‐arylimidoyl)k:etenes 4a‐d as intermediates which undergo a very facile cyclization to quinoline‐4‐ones 5a‐d . According to our PM3 calculations, fragmentation of 4‐formyl‐2,3‐dihydro‐1H‐pyrole‐2,3‐dione and 1,4‐cyclization of formyl(N‐phenylimidoyl)k:etene IN1 to azetin‐2‐one IN2 and oxe‐tone IN3 are pseudopericyclic reactions with two orbital connections, proceed via planar transition structures. Due to to the possibility of syn and anti conformations of the imine phenyl, there are eight E/Z‐iso‐mers of IN1 . In addition, we have also calculated reaction mechanism of formation of quinoline‐4‐ones by the PM3 method. 相似文献
2.
Kazuhiro Kobayashi Natsuki Konishi Teruhiko Suzuki Kazuhiro Nakagawa 《Helvetica chimica acta》2013,96(8):1452-1456
An efficient one‐pot synthesis of novel heterocyclic derivatives, 2‐aryl‐1,4‐oxathiino[2,3‐b]quinoxalines or ‐pyrazines 5 , via the reaction of 2,3‐dichloroquinoxaline or ‐pyrazine with Na2S?9 H2O, and subsequent treatment of the resulting 2‐chloro‐3‐sodiosulfanylquinoxaline or ‐pyrazine 2 with 1‐aryl‐2‐bromo‐1‐alkanones and then NaH under mild conditions is described. 相似文献
3.
Noboru Matsumura Osamu Mori Toshio Takeguchi Yasuyuki Okumura Kazuhiko Mizuno 《Journal of heterocyclic chemistry》2004,41(6):873-876
Photoirradiation of acetone solutions of 2,3‐diallyl‐6,7‐dihydro‐5H‐2a‐thia(2a‐SIV)‐2,3,4a, 7a‐tetraazacyclopent[cd]indene‐ 1,4(2H,3H)‐dithione ( 1 ) in the presence of excess thioacetic acid and thiobenzoic acid afforded addition products, 2,3‐bis(3‐acetylthiopropyl)‐ and 2,3‐bis(3‐benzoylthiopropyl)‐6,7‐dihydro‐5H‐2a‐thia(2a‐SIV)2,3,4a, 7a‐tetraazacyclopent[cd]indene‐1,4(2H,3H)‐dithiones, respectively, in good yields. These photoaddition reactions were facilitated by the addition of oxygen. 相似文献
4.
Insuasty O. Braulio Insuasty I. Henry Quiroga P. Jairo Claudio Saitz Carolina Jullian 《Journal of heterocyclic chemistry》2000,37(2):401-403
Several new 6‐amino‐ and 6,8‐diamino‐4‐aryl‐2,3‐dihydropyrimido[4,5‐b][1,4]diazepines were obtained from the reaction of 4,5,6‐triaminopyrimidine 1a and 2,4,5,6‐tetraaminopyrimidine 1b with one equivalent of 3‐dimethylaminopropiophenones 2 in absolute ethanol. Structure analysis of 6‐amino‐ and 6,8‐diamino‐4‐aryl‐2,3‐dihydropyrimido[4,5‐b][1,4]diazepines 3a‐i , determined by detailed nmr measurements, reveals a high regioselectivity of this reaction. 相似文献
5.
《化学:亚洲杂志》2017,12(18):2399-2403
An intramolecular exo ‐hydroarylation of 2‐aryloxy‐1,4‐disilylbut‐1‐en‐3‐ynes via ortho ‐C−H bond activation under palladium(0) and acid catalysis was found to give 2,3‐bis(silylmethylidene)‐2,3‐dihydrobenzofurans. The two silyl groups present probably promoted the reaction and played a key role in stabilizing the diene moiety in the product. The products readily led to functionalized condensed cycles by a Diels–Alder reaction. 相似文献
6.
Kamal M. El‐Shaieb 《中国化学会会志》2007,54(5):1353-1358
When 2,3‐dichloro‐1,4‐naphthoquinone (DCHNQ) ( 1 ) is allowed to react with 1‐phenylbiguanide (PBG) ( 2 ), 4‐chloro‐2,5‐dihydro‐2,5‐dioxonaphtho[1,2‐d]imidazole‐3‐carboxylic acid phenyl amide ( 4 ), 6‐chloro‐8‐phenylamino‐9H‐7,9,11‐triaza‐cyclohepta[a]naphthalene‐5,10‐dione ( 5 ) and 4‐dimethyl‐amino‐5,10‐dioxo‐2‐phenylimino‐5,10‐dihydro‐2H‐benzo[g]quinazoline‐1‐carboxylic acid amide ( 6 ) were obtained. While on reacting 1 with 2‐guanidinebenzimidazole (GBI) ( 3 ) the products are 3‐(1H‐benzoimidazol‐2‐yl)‐4‐chloro‐3H‐naphtho[1,2‐d]imidazole‐2,5‐dione ( 7 ) and 3‐[3‐(1H‐benzoimidazol‐2‐yl)‐ureido]‐1,4‐dioxo‐1,4‐dihydronaphthalene‐2‐carboxylic acid dimethylamide ( 8 ). 相似文献
7.
Stanislas Mayer Axelle Arrault GRald Guillaumet Jean‐Yves Mrour 《Journal of heterocyclic chemistry》2001,38(1):221-225
Ethyl 3,4‐dihydro‐2H‐1,4‐benzoxazine‐3‐carboxylate derivatives 2 were obtained and isolated in low yields from the condensation of 2‐aminophenol and ethyl 2,3‐dibromopropanoate. They can be obtained by hydrogenation of ethyl 2H‐1,4‐benzoxazine‐3‐carboxylate in satisfactory yield. Using 2‐iminophenol did not direct the condensation with ethyl 2,3‐dibromopropanoate towards 2 but was fruitfull for the preparation of ethyl 2‐(4‐benzyl‐3,4‐dihydro‐2H‐1,4‐benzoxazin‐3‐yl)acetate from ethyl bromocrotonate. 相似文献
8.
Ashraf A. Aly Alaa A. Hassan Alan B. Brown Kamal M. El‐Shaieb Tarek M. I. Bedair 《Journal of heterocyclic chemistry》2011,48(4):787-791
New imidazoles were easily prepared from 2,3‐diamino‐1,4‐naphthoquinone and stoichiometric quantities of the appropriate aldehydes in dimethyl sulfoxide as a solvent. The reaction proceeded for few hours. The procedure can be generalized to different classes of aldehydes. 2‐Methyl‐1H‐naphtho[2,3‐d]imidazole‐4,9‐dione was also obtained in good yield during refluxing of 2,3‐diaminonaphthoquinone in acetic acid. The structure of the newly synthesized imidazoles was extensively investigated using NMR experiments. J. Heterocyclic Chem., (2011). 相似文献
9.
A Novel Diastereoselective Synthesis of 6‐Aryl‐5‐hydroxy‐2,3‐dihydropyrano[2,3‐c]pyrazol‐4(1H)‐ones
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Samir Bondock 《Journal of heterocyclic chemistry》2014,51(1):127-131
A novel one‐pot diastereoselective synthesis of trans‐6‐aryl‐5‐hydroxy‐2,3‐dihydro[2,3‐c]pyrazol‐4(1H)‐ones 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h is described via the Darzens condensation reaction of 2‐chloro‐1‐(5‐hydroxy‐3‐methyl‐1‐phenyl‐1H‐pyrazol‐4‐yl)ethanone ( 2 ) with different aromatic aldehydes in aqueous basic medium. The structures of the compounds prepared were determined by analytical and spectral analyses. 相似文献
10.
11.
Kirill Popov Tatyana Volovnenko Yulian Volovenko 《Journal of heterocyclic chemistry》2013,50(Z1):E217-E220
A simple, efficient, and clean protocol for the formylation of 2,3‐dihydro‐4H‐1,4‐benzo[e][1,4]thiazin‐3‐on‐1,1‐dioxide is developed. Novel benzothiazine derivatives are synthesized by the reactions of aminovinyl derivative 6 and carbaldehyde 7 with nucleophiles. 相似文献
12.
Green Approach to the Design of Functionalized Medicinally Privileged 4‐Aryl‐1,4‐dihydropyrano[2,3‐c]‐pyrazole‐5‐carbonitrile Scaffold
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Alexey I. Ilovaisky Michael G. Medvedev Valentina M. Merkulova Michail N. Elinson Gennady I. Nikishin 《Journal of heterocyclic chemistry》2014,51(2):523-526
“On water” multicomponent condensation of aromatic aldehydes, malononitrile, and 3‐methyl‐2‐pyrazoline‐5‐one in the presence of sodium hydroxide as catalyst leads to 6‐amino‐3‐methyl‐4‐aryl‐1,4‐dihydropyrano[2,3‐c]pyrazole‐5‐carbonitriles in 85–98% yields. 相似文献
13.
Albert Lévai József Jekő Tímea Gondos András Simon Gábor Tóth 《Journal of heterocyclic chemistry》2007,44(6):1453-1458
14.
Alaa A. Hassan Nasr K. Mohamed Lamiaa E. Abd El‐Haleem Stefan Bräse Martin Nieger 《中国化学》2016,34(8):814-822
A one step synthesis protocol for the conversion of heteroylthiosemicarbazides and 2,3‐dichloro‐1,4‐naphthoquinone to naphtho[2,3‐d]thiazoles, naphtho[2,3‐e][1,3,4]thiadiazines as well as bis(naphtho[2,3‐d]thiazolyl)copper(II) derivatives is described. The products were conclusively confirmed by single crystal X‐ray analyses. A mechanism for the formation of the products is presented. 相似文献
15.
A facile synthesis of the imidazo[1,5‐d]thieno[2,3‐b][1,4]thiazine ring system is described. Reaction of 6‐benzyl‐2,3‐dihydro‐1H‐thieno[2,3‐b][1,4]thiazine‐2‐one ( 1 ) with potassium tert‐butoxide and diethylchlorophosphate gave intermediate 2 which resulted in the disired ring system after adding the corresponding isocyanides and potassium tert‐butoxide. 相似文献
16.
Synthesis of 5,7‐Disubstituted 7H‐Pyrrolo[2,3‐d]Pyrimidin‐4(3H)‐ones and Their N‐Alkylation's under Phase Transfer Conditions
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5,7‐disubstituted 7H‐pyrrolo[2,3‐d]pyrimidin‐4(3H)‐ones 2 were synthesized by the cyclocondensation of 1,4‐disubstituted 2‐amino‐3‐cyanopyrrole 1 with formic acid. When comparative study of N versus O alkylation of ambident 5,7‐disubstituted 7H‐pyrrolo[2,3‐d]pyrimidin‐4(3H)‐ones 2 was carried out under liquid–liquid PTC, solid–liquid PTC, and solid–liquid solvent free conditions using various alkylating agents 3 , the N‐alkylated product 4 were obtained selectively and exclusively. 相似文献
17.
Polyamides containing 1,4‐dithiin‐2,3 : 5,6‐tetrayl diimide structures were synthesised by condensation reaction of bis[N,N′‐(4‐chlorocarbonylphenyl)‐1,4‐dithiin‐2,3 : 5,6‐tetrayl diimide] ( 3 ) with various aromatic diamines. Monomer 3 was synthesised by nucleophilic substitution of N‐(4‐carboxyphenyl)‐3,4‐dichloromaleimide ( 1 ) with sodium sulfide nonahydrate. Their structures were confirmed by IR and UV spectroscopy, as well as elemental analysis. The polymers were characterised by viscometric measurements, softening points and thermogravimetric data. They showed good solubility in aprotic solvents and high thermal stability with the decomposition temperature being in the range 392–415°C. 相似文献
18.
Amrah Nouri Ahmad Poursattar Marjani Jabbar Khalafy 《Journal of heterocyclic chemistry》2019,56(10):2912-2921
A new series of benzo[g]thiazolo[2,3‐b]quinazolin‐4‐ium and benzo[g]benzo[4,5]thiazolo[2,3‐b]quinazolin‐14‐ium hydroxide derivatives have been synthesized by the one‐pot, three‐component reaction of aryl glyoxal monohydrates, 2‐hydroxy‐1,4‐naphthoquinone, and 2‐aminothiazole or 2‐aminobenzothiazole in the presence of triethylamine and p‐toluenesulfonic acid as organocatalysts in H2O/acetone (2:1) at room temperature. This method offers mild reaction conditions, excellent yields, easy workup, and readily accessible starting materials and catalysts. 相似文献
19.
Eduardo Cortés Erik Peréz Ramírez Olivia García‐Mellado de Cortés 《Journal of heterocyclic chemistry》2007,44(1):189-192
20.
New Convenient Five‐Component One‐Pot Synthesis of 3‐Alkyl‐6‐amino‐1,4‐dihydro‐4‐{[(1,2,3‐triazol‐4‐yl)methoxy]phenyl}pyrano[2,3‐c]pyrazole‐5‐carbonitrile Derivatives
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Minoo Dabiri Peyman Salehi Mahsa Fakharian Siyavash Kazemi Movahed David I. MaGee 《Helvetica chimica acta》2015,98(5):633-641
3‐Alkyl‐6‐amino‐1,4‐dihydro‐4‐{[(1,2,3‐triazol‐4‐yl)methoxy]phenyl}pyrano[2,3‐c]pyrazole‐5‐carbonitrile derivatives were synthesized through a one‐pot five‐component condensation reaction. 相似文献