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1.
Reaction of 3-(Dimethylamino)-2H-azirines with 1,3-Benzoxazole-2(3H)-thione The reaction of 3-(dimethylamino)-2H-azirines 2 with 1,3-benzoxazole-2(3H)-thione ( 5 ), which can be considered as NH-acidic heterocycle (pKaca. 7.3), in MeCN at room temperature, leads to 3-(2-hydroxyphenyl)-2-thiohydantoins 6 and thiourea derivatives of type 7 (Scheme 2). A reaction mechanism for the formation of the products via the crucial zwitterionic intermediate A ′ is suggested. This intermediate was trapped by methylation with Mel and hydrolysis to give 9 (Scheme 4). Under normal reaction conditions, A ′ undergoes a ring opening to B which is hydrolyzed during workup to yield 6 or rearranges to give the thiourea 7. A reasonable intermediate of the latter transformation is the isothiocyanate E (Scheme 3) which also could be trapped by morpholine. In i-PrOH at 55–65° 2a and 5 react to yield a mixture of 6a , 2-(isopropylthio)-1,3-benzoxazole ( 12 ), and the thioamide 13 (Scheme 5). A mechanism for the surprising alkylation of 5 via the intermediate 2-amino-2-alkoxyaziridine F is proposed. Again via an aziridine, e.g. H ( Scheme 6 ), the formation of 13 can be explained. 相似文献
2.
Simon M. Ametamey Roland Prewo Jost H. Bieri Heinz Heimgartner Jean Pierre Obrecht 《Helvetica chimica acta》1986,69(8):2013-2025
Reaction of 3-(Dimethylamino)-2H-azirines with 1,3-Thiazolidine-2-thione Reaction of 3-(dimethylamino)-2H-azirines 1 and 1,3-thiazolidine-2-thione ( 6 ) in MeCN at room temperature leads to a mixture of perhydroimidazo[4,3-b]thiazole-5-thiones 7 and N-[1-(4,5-dihydro-1,3-thiazol-2-yl)alkyl]-N′,N′-dimethylthioureas 8 (Scheme 2), whereas, in i-PrOH at ca. 60°, 8 is the only product (Scheme 4). It has been shown that, in polar solvents or under Me2NH catalysis, the primarily formed 7 isomerizes to 8 (Scheme 4). The hydrolysis of 7 and 8 leads to the same 2-thiohydantoine 9 (Scheme 3 and 5). The structure of 7a, 8c , and 9b has been established by X-ray crystallography (Chapt. 4). Reaction mechanisms for the formation and the hydrolysis of 7 and 8 are suggested. 相似文献
3.
Krishna C. Joshi Anshu Dandia Sangeeta Sanan 《Journal of heterocyclic chemistry》1989,26(5):1397-1400
The reaction of 3-(2-oxocycloalkylidene)indol-2-one 1 with thiourea and urea derivatives has been investigated. Reaction of 1 with thiourea and urea in ethanolic potassium hydroxide media leads to the formation of spiro-2-indolinones 2a-f in 40–50% yield and a novel tetracyclic ring system 4,5-cycloalkyl-1,3-diazepino-[4,5-b]indole-2-thione/one 3a-f in 30–35% yield. 3-(2-Oxocyclopentylidene)indol-2-one afforded 5′,6′-cyclopenta-2′-thioxo/ oxospiro[3H-indole-3,4′(3′H)pyrimidin]-2(1H)-ones 2a,b and 3-(2-oxocyclohexylidene)indol-2-one gave 2′,4′a,5′,6′,7′,8′- hexahydro-2′-thioxo/oxospiro[3H-indole-3,4′ (3′H)-quinazolin]-2(1H)-ones 2c-f . Under exactly similar conditions, reaction of 1 with fluorinated phenylthiourea/cyclohexylthiourea/phenylurea gave exclusively spiro products 2g-1 in 60–75% yield. The products have been characterized by elemental analyses, ir pmr. 19F nmr and mass spectral studies. 相似文献
4.
The reaction of 3-(dimethylamino)-2H-azirines 1a–c and 2-amino-4,6-dinitrophenol (picramic acid, 2 ) in MeCN at 0° to room temperature leads to a mixture of the corresponding 1,2,3,4-tetrahydroquinazoline-2-one 5 , 3-(dimethylamino)-1,2-dihydroquinazoline 6 , 2-(1-aminoalkyl)-1,3-benzoxazole 7 , and N-[2-(dimethylamino)phenyl]-α-aminocarboxamide 8 (Scheme 3). Under the same conditions, 3-(N-methyl-N-phenyl-amino)-2H-azirines 1d and 1e react with 2 to give exclusively the 1,3-benzoxazole derivative 7 . The structure of the products has been established by X-ray crystallography. Two different reaction mechanisms for the formation of 7 are discussed in Scheme 6. Treatment of 7 with phenyl isocyanate, 4-nitrobenzoyl chloride, tosyl chloride, and HCl leads to a derivatization of the NH2-group of 7 (Scheme 4). With NaOH or NaOMe as well as with morpholine, 7 is transformed into quinazoline derivatives 5 , 14 , and 15 , respectively, via ring expansion (Scheme 5). In case of the reaction with morpholine, a second product 16 , corresponding to structure 8 , is isolated. With these results, the reaction of 1 and 2 is interpreted as the primary formation of 7 , which, under the reaction conditions, reacts with Me2NH to yield the secondary products 5 , 6 , and 8 (Scheme 7). 相似文献
5.
Nurani S. Narasimhan Heinz Heimgartner Hans-Jürgen Hansen Hans Schmid 《Helvetica chimica acta》1973,56(4):1351-1370
Benzonitrile p-nitrobenzylide ( 5 ) undergoes 1,3-dipolar cyclo-additions in the presence of 3-phenyl-2H-azirines ( 1 ), yielding in benzene at 0° 2-(p-nitrophenyl)-4,5-diphenyl-1,3-diazabicyclo[3.1.0]hex-3-enes ( 7 , scheme 2). Under the basic conditions of the reaction mixture, 7 a and 7 b are partially converted to 2-(p-nitrophenyl)-4,5-diphenyl-1,6-dihydropyrimidines ( 8a, b ) which are dehydrogenated by oxygen to the corresponding pyrimidines 9a and 9b , respectively. 3-Phenyl-2H-azirines ( 1 ) form, on heating at 145° in xylene in the presence of the azalactone 32 (2,4-diphenyl-Δ2-oxazolin-5-one), 4-(aziridin-2′-yl)-2,4-diphenyl-Δ2-oxazolin-5-ones ( 33 , scheme 11). 33 arises from an ene reaction of the enol form of 32 with 1 . Similar ene reactions are observed with the azirines 1 and dimedone ( 37 , scheme 12). Under the ene reaction conditions (xylene, 145°), the non-isolated intermediate primary adducts ( 38a and 38b ) undergo rearrangements of the vinylcyclopane-cyclopentene type to give 6,6-dimethyl-4-oxo-1,3-diphenyl-4, 5, 6, 7-tetrahydroisoindole ( 40 ) and 6, 6-dimethyl-4-oxo-3-phenyl-4, 5, 6, 7-tetrahedroindole ( 42 ), respectively. 相似文献
6.
Persephone Canonne Raynald Boulanger Bernard Chantegrel 《Journal of heterocyclic chemistry》1989,26(1):113-117
A one-step synthesis of spiro[cycloalkane-1,4′-2H-3′,1-benzoxazin]-2′-ones and spiro[cycloalkane-1,4′-1H-pyrido[2′,3′-d][1,3′]oxazin]-2′-ones, obtained in good yield from the corresponding 1-(o-aminophenyl) and 1-(2′-amino-3′-pyridinyl)cycloalkanols is described using ethyl carbonate in presence of n-butyllithium. 相似文献
7.
Synthesis of 3,3′-(1,6-hexanediyl)bis-pyrimidine derivatives and 3,4-dithia[6.6](1.3)pyrimidinophane
Toshio Kinoshita Shirou Odawara Keiko Fukumura Sunao Furukawa 《Journal of heterocyclic chemistry》1985,22(6):1573-1576
Several 3,3′-(1,6-hexanediyl)bis[6-methyl-2,4(1H,3H)-pyrimidinedione] derivatives ( 4a, 4b , and 4c ) were synthesized from 1,6-(hexanediyl)bis[6-methyl-2H-1,3-oxazine-2,4(3H)-dione] (3) . Compound 4c was converted to 6, which reacted with thiourea giving thiuronium salt 7 . 3,3′-(1,6-Hexanediyl)bis [1-(2-mercaptoethyl)-6-methyl-2,4(1H,3H)-pyrimidinedione] (9) was obtained by the hydrolysis of 7 , and then 9 was oxidized to 12,22-dimethyl-3,4-dithia[6.6] (1.3)-1,2,3,4-tetrahydro-2,4-dioxopyrimidinophane (10) . 相似文献
8.
1H,3H-Imidazo[1,5-c]thiazole-5,7-[6H,7aH]-dione and the corresponding 7-thione derivatives as well as 7,8-dihydro-5H-imidazo[1,5-c][1,3]thiazine-1,3-[2H,8aH]-dione and the corresponding 3-thione derivatives were synthesized starting from L -cysteine and DL -homocysteine thiolactone, respectively. The second group of bicyclic compounds represents a new heterocyclic ring system. The structures of the compounds were confirmed by spectroscopic studies and elemental analyses. 相似文献
9.
Reactions of 3-methyl-6-[4-(4-hydroxyphenyl)-1-piperazinyl]-2(3H)-benzoxazolone, 3-methyl-6-[4-(4-hydroxy-phenyl)-1-piperazinyl]-2(3H)-benzothiazolone and 1,3-dimethyl-5-[4-(4-hydroxyphenyl)-1-piperazinyl]-2(3H)-benzimidazolone with cis-{[2-(2,4-dichlorophenyl) -2-(1H-imidazol-1-ylmethyl)]-1,3-dioxolan-4-yl}methyl meth-anesulfonate in the presence of sodium hydride furnish the title compounds. 相似文献
10.
Ricardo Bossio Stefano Marcaccini Valerio Parrini Roberto Pepino 《Journal of heterocyclic chemistry》1985,22(4):1147-1148
2-(Benzimidazol-2-ylamino)pyridine (4a) , 2-(benzimidazol-2-ylamino)pyrazine (4b) , and 2-(benzimidazol-2-ylamino)thiazole (4c) underwent a ring-closure reaction on treatment with phosgene affording 6H-pyrimido-[1′,2′:5,4][1,3,5]triazino[1,2-a]benzimidazol-6-one (1a) , 6H-pyrazino[1′,2′:5,4][1,3,5]triazino[1,2-a]benzimidazol-6-one (1b) , and 5H-thiazolo[2′,3′:4,5][1,3,5]triazino[1,2-a]benzimidazol-5-one (1c) respectively. The structure of these hitherto unknown heterocyclic systems was confirmed by their ir and mass spectra. 相似文献
11.
Daniel Obrecht Roland Prewo Jost H. Bieri Heinz Heimgartner 《Helvetica chimica acta》1982,65(6):1825-1836
1,3-Dipolar Cycloadditions of 2-(Benzonitrilio)-2-propanide with 4,4-Dimethyl-2-phenyl-2-thiazolin-5-thione and Carbon Disulfide Irradiation of 2,2-dimethyl-3-phenyl-2H-azirine ( 11 ) in the presence of 4,4-dimethyl-2-phenyl-2-thiazolin-5-thione ( 7 ) yields a mixture of the three (1:1)-ad-ducts 8 , 12 and 13 (Schemes 3 and 6). The formation of 8 and 12 can be explained by 1,3-dipolar cycloaddition of 2-(benzonitrilio)-2-propanide ( 1b ) to the C, S-double bond of 7. Photochemical isomerization of 12 leads to the third isomer 13 (Schemes 3 and 7). Photolysis of the azirine 11 in the presence of carbon disulfide gives a mixture of two (2:l)-adducts, namely 12 and 13 (Scheme 4). A reaction mechanism via the intermediate formation of the 3-thiazolin-5-thione b is postulated. The structure of the heterocyclic spiro compound 13 has been established by single-crystal X-ray structure determination (cf. Fig. 1 and 2). 相似文献
12.
Dyachenko V. D. Dyachenko A. D. Chernega A. N. 《Russian Journal of Organic Chemistry》2004,40(3):397-406
Cyclopentylidene- and cyclohexylidene(cyano)acetamides reacted with malononitrile and cyano-(thioacetamide) according to the Michael pattern with exchange of the methylene components to give substituted 1-amino-2,6,6-tricyano-1,3-cyclohexadienes and thieno[2,3-d]pyrimidine-4(3H)-thiones. Condensation of cyclopentylidene- and cyclohexylidene(cyano)acetamide with 1,3-dicarbonyl compounds afforded 4,6-di-methyl-3-cyanopyridine-2(1H)-thione and morpholinium 4-methyl-6-oxo-3-cyano-1,6-dihydropyridine-2-thiolate which were converted into substituted 2-alkylsulfanylpyridines, thieno[2,3-b]pyridines, thiazolo[3,2-a]pyridine, and 2H-[1,3]thiazino[3,2-a]pyridine. 相似文献
13.
Reactions of 3-(Dimethylamino)-2,2-dimethyl-2H-azirines with Barbituric-Acid Derivatives The reaction of 3-(dimethylamino)-2,2-dimethyl-2H-azirine ( 1 ) and 5,5-disubstituted barbituric acids 5 in i-PrOH at ca. 70° gives 2-[5-(dimethylamino)-4,4-dimethyl-4H-imidazol-2-yl]alkanamides of type 6 in good yields (Scheme 1). The formation of 6 proceeds with loss of CO2; various reaction mechanisms with a zwitterionic 1:1 adduct B as common intermediate are discussed (Schemes 2 and 5). Thermolysis of product 6 leads to 2-alkyl-5-(dimethylamino)-4,4-dimethyl-4H-imidazoles 8 or the tautomeric 2-alkylidene derivatives 8 ′ via elimination of HNCO (Scheme 3). The latter undergoes trimerization to give 1,3,5-triazine-2,4,6-trione. No reaction is observed with 1,5,5-trisubstituted barbiturates and 1 in refluxing i-PrOH, but an N-alkylation of the barbiturate occurs in the presence of morpholine (Scheme 4). This astonishing reaction is explained by a mechanism via formation of the 2-alkoxy-2-(dimethylamino )aziridinium ion H which undergoes ring opening to give the O-alkylated 2-amino-N1,N1-dimethylisobutyramide I as alkylating reagent (Scheme 4). 相似文献
14.
The reactions of dimethyl acetylenecarboxylate with 3,4,5,6-tetrahydro-2H-1,2,4-triazepine-3-thiones and 4,5-dihydro-1H-pyrazole-1-carbothioamides are convenient methods for the synthesis of 7,8-dihydrothiazolo[3,2-b][1,2,4]triazepin-3-ones derivatives and methyl esters of (2Z)-[2-(4,5-dihydro-1H-pyrazol-1-yl)-4-oxo-1,3-thiazol-5(4H)-ylidene]acetic acids, respectively. The reaction of methyl propynoates with 4,5-dihydro-1H-pyrazole-1-carbothioamides or with 5,5,7-trimethyl-2,4,5,6-tetrahydro-3H-1,2,4-triazepine-3-thione gives 2-(4,5-dihydro-1H-pyrazol-1-yl)-4H-1,3-thiazin-4-ones. 相似文献
15.
Massimo Pregnolato Pietro Borgna Marco Terreni 《Journal of heterocyclic chemistry》1995,32(3):847-850
A convenient synthesis of 3H-thieno[3,2-c]-1,2-dithiole-3-thione (7) is proposed. The reaction of 7 with n-butylamine afforded the N-butylthieno[3,2-c]isothiazole-3(2H)-thione (7a) in dynamically equilibrium [1] with its 3H-thieno[3,2-c]-1,2-dithiole-N-butyl-3-imino isomer 7b. Characterizations and antimicrobial activities of the synthesized products are reported. 相似文献
16.
Reaction of 3-Amino-2H-azirines with Diphenylcyclopropenethione 3-Dimethylamino-2H-azirines ( 4a , 4b ) react with diphenylcyclopropenethione ( 8 ) to give 4(3 H)-pyridinethione derivatives of type 10 (Scheme 3). The reaction mechanism for the formation of 10 is given in Scheme 3 by analogy with a previous reported one [4] [5]. Hydrolysis of the 4(3 H)-pyridinethione 10a yields 2-oxo-2, 3-dihydro-4(1 H)-pyridinethione ( 11 ) and reduction of 10a with sodium borohydride leads to the 2, 3-dihydro-4 (1 H)-pyridinethione 12 (Scheme 4). The results of the reaction of 4a , 4b and the thione 8 demonstrate the similarity to the reaction of 4a , 4b and 2 [5] (cf. Scheme 1). In contrast, the reactions of imines of type 7a with 2 and 8 , respectively, lead to different products (cf. [1] [6]). 相似文献
17.
Dipolar 1:1 Adducts from the Reaction of 3-Amino-2H-azirines with 1,3,4-Oxadiazol- and 1,3,4-Thiadiazol-2(3H)-ones 3-Amino-2H-azirines 1 react with 5-(trifluoromethyl)-1,3,4-oxadiazol-2(3H)-one ( 2 ) as well as with different 5-substituted 1,3,4-thiadiazol-2(3H)-ones ( 5a–e ) in 2-propanol at room temperature to give dipolar 1:1 adducts of type 3 and 6 , respectively, in reasonable-to-good yields (Schemes 3 and 6, Tab. 1 and 2). The structure of two of these dipolar adducts, 6a and 6e , which are formally donor-acceptor-stabilized azomethin imines, have been elucidated by X-ray crystallography (Figs. 1-4). In the reaction of 2 and sterically crowded 3-amino-2H-azirines 1c–e with a 2-propyl and 2-propenyl substituent, respectively, at C(2), a 4,5-dihydro-1,2,4-triazin-3(2H)-one of type 4 is formed as minor product (Scheme 3 and Table 1). Independent syntheses of these products proved the structure of 4 . Several reaction mechanisms for the formation of compounds 3 and 4 are discussed, the most likely ones are described in Scheme 4: reaction of 2 as an NH-acidic compound leads, via a bicyclic zwitterion of type A , to 3 as well as to 4 . In the latter reaction, a ring-expanded intermediate B is most probable. 相似文献
18.
An Unexpected Ring Enlargement of 3-(Dimethylamino)-2,2-dimethyl-2H-azirine to 4,5-Dihydropyridin-2(3H)-one Derivatives The reaction of 3-(dimethylamino)-2,2-dimethyl-2H-azirine ( 1a ) and 4,4-disubstituted 2-(trifluoromethyl)-1,3-oxazol-5(4H)-ones 7 in MeCN at 70° afforded 5-(dimethylamino)-3,6-dihydropyrazin-2(1H)-ones 10 (Scheme 4), whereas no reaction could be observed between 1a and 2-allyl-4-phenyl-2-(trifluoromethyl)-1,3-oxazol-5(2H)-one ( 8a ) or 4,4-dibenzyl-2-phenyl-1,3-oxazol-5(4H)-one ( 9 ). The formation of 10 is rationalized by a mechanism via nucleophilic attack of 1a onto 7 . The failure of a reaction with 9 shows that only activated 1,3-oxazol-5(4H)-ones bearing electron-withdrawing substituents do react as electrophiles with 1a . The amino-azirine 1a and 2,4-disubstituted 1,3-oxazol-5(4H)-ones 2b – e in refluxing MeCN undergo a novel ring enlargement to 4,5-dihydropyridin-2(3H)-ones 11 (Scheme 5). Several side products were observed in these reactions. Two different reaction mechanisms for the formation of 11 are proposed: either 1a undergoes a nucleophilic addition onto the open-chain ketene tautomer of 2 (Scheme 6), or 2 reacts as CH-acidic compound (Scheme 7). 相似文献
19.
Kozlov N. G. Basalaeva L. I. Odnoburtsev B. A. 《Russian Journal of Organic Chemistry》2010,46(5):740-745
Reactions of azomethines (Schiff bases) prepared from vanillin and vanillal ethers and 1-naphthylamine with cyclohexane-1,3-dione
in butanol afforded in 40–64% yields 7-[4-alkoxy-3-methoxy(hydroxy)phenyl]-10,11-dihydrobenzo[c]acridin-8(7H,9H,12H)-ones and 4-(8-oxo-7,8,9,10,11,12-hexahydrobenzo[C]acridin-7-yl)-2-methoxy(ethoxy)phenyl esters of carboxylic acids. The
reaction products presumably formed by the rearrangement of the azomethine adduct with the cyclohexane-1,3-dione proceeding
by the type of Hofmann-Martius rearrangement. The structure of compounds synthesized was confirmed by the elemental analysis,
UV, IR, and 1H NMR spectra. 相似文献
20.
LSzl Pong PL Sohr J
Zsef Reiter Pter Dvortsk Gyrgy Bujts 《Journal of heterocyclic chemistry》1994,31(4):997-1004
The reaction of potassium (5-amino-3-Q-1,2,4-triazolyl)dithiocarbonates 2 with 1,ω-dihaloalkanes 7-10 to yield ω-haloalkyldithiocarbonates 11-12 , ω-alkylene-bis(dithiocarbonates) 13-15 and different by-products as the corresponding 7,8-dihydro[1,2,4]triazolo[1,5-c][1,3,5]thiadiazepine-5(9H)-thione ( 16 ), 7,8,9,10-tetrahy-dro[1,2,4]triazolo[1,5-c][1,3,5]thiadiazocine-5-thione ( 17 ) and 1,7-dihydro-5H-1,2,4-triazolo[1,5-c][1,3,5]thiadi-azine-5-thione ( 22 ) derivatives all three representing novel ring systems were obtained. Repeating the reactions with dipotassium salts 3 the corresponding iminodithietans 18 , imino-1,3-dithiolanes 19 and imino-1,3-dithianes 20 were obtained. Unexpectively, the imino-1,3-dithiolanes ( 19 ) rearranged to the corresponding thiazolidines 24-27 under rather mild conditions. A possible mechanism is proposed for this rearrangement. 相似文献