Synthesis of 1,4-dihydro-4-methyl-1-phenyl-5H-1,3,4-benzotriazepin-5-ones

The synthesis of 1,4-dihydro-4-methyl-1-phenyl-5H-1,3,4-benzotriazepin-5-one ( 4a ) and its 8-chloro analog ( 4b ) is described. Attempted synthesis of the 2-methyl analog of 4a from 2-(phenylamino)benzoic acid 1-methylhydrazide ( 10 ) and triethyl orthoaeetate led only to the Schiff base intermediate, 2-(phenylamino)benzoic acid 2-(1-ethoxyethylidene)-1-methylhydrazide ( 11 ). Cyclization of 11 was attempted unsuccessfully with a variety of reagents. The intere?ting reaction products from the treatment of 11 with trifluoroacetic acid are described.     

Facile Synthesis of Dihydro-1,2,4-benzotriazepin-5-ones

Direct interaction between model anilines and an 1,3-dipolar nitrile imine, derived from 2-[N′-(1-chloro-2-oxopropylidine)hydrazine]benzoic acid, yielded the respective acyclic amidrazones. The latter adducts underwent CDI-induced cyclocondensation involving the hydrazone–NH terminus and the activated carboxy group to produce the corresponding dihydro-1,2,4-benzotriazepin-5-ones.     

Facile Synthesis of Dihydro-1,2,4-benzotriazepin-5-ones

Summary. Direct interaction between model anilines and an 1,3-dipolar nitrile imine, derived from 2-[N′-(1-chloro-2-oxopropylidine)hydrazine]benzoic acid, yielded the respective acyclic amidrazones. The latter adducts underwent CDI-induced cyclocondensation involving the hydrazone–NH terminus and the activated carboxy group to produce the corresponding dihydro-1,2,4-benzotriazepin-5-ones.     

The cyelodesulfurization of thio-compounds. Part XVII. Synthesis of some novel 2-substituted amino-3,4-dihydro-5H-1,3,4-benzotriazepin-5-ones by cyelodesulfurization of thiosemicarbazides with dicyclohexylearbodiimide (DCCD)

A simple method for the synthesis of a novel series of 2-substituted amino-3,4-dihydro-5H-1,3,4-benzotriazepin-5-ones (11–16) has been established through two routes. The first involving the cyelodesulfurization of the thiosemicarbazides (3–8) with DCCD and the second reacting mixtures of the acid hydrazide 1 with a variety of the isothiocyanates 2 and DCCD. The structure of the cyclized products was confirmed by nmr and mass spectra.     

Selective synthesis of novel 2-imino-1,3-selenazolidin-4-ones and 2-amino-1,3,4-selenadiazin-5-ones from isoselenocyanates

An efficient and regioselective synthesis of 2-imino-1,3-selenazolidin-4-ones and 2-amino-1,3,4-selenadiazin-5-ones was achieved via one-pot reaction of isoselenocyanates, hydrazines, and ethyl chloroacetate or chloroacetyl chloride, respectively. Plausible mechanisms for these transformations were given.     

Syntheses and structures of new substituted 4-aryl-sulfonyl-4H-1,3,4-thiadiazin-5(6H)-ones

The cyclization of 4-aryl-1-arylsulfonylthiosemicarbazides 3, which were prepared by treatment of arylsulfonyl chlorides 1 with 4-aryl-3-thiosemicarbazides 2, with chloroacetyl chloride, provided the corresponding 2-arylamino-4-arylsulfonyl-4H-1,3,4-thiadiazin-5(6H)-ones 4 in good yields. The structures of all these compounds were evaluated by elemental analyses, and ¹HNMR, and IR spectroscopy. The structure of compound 4f was ascertained by X-ray diffraction analysis. © 1997 John Wiley & Sons, Inc.     

1,3,4-Thiadiazoles. XI. Synthesis and behaviour of 4-Alkyl-5-acyl-1,3,4-thiadiazolines

The synthesis of the title compounds from thiadiazolium salts and aldehydes, and their behaviour towards some nucleophiles and aldehydes are described.     

An efficient preparation of 4-arylmethylisoxazol-5-ones by selective reduction of the 4-arylmethyleneisoxazol-5-ones

An efficient selective reduction of the exocyclic double bond of the 4-arylmethyleneisoxazol-5-ones with o-phenylenediamines and aldehydes is described. 4-arylmethylisoxazol-5-ones are produced in high yields together with comparable quantities of benzimidazoles.     

Fused v-triazolo-heterocycles. Part 2. Synthesis of 4H-v-triazolo[1,5-d] [1,3,4]oxadiazin-4-ones from the 1-aroylamino-v-triazole-5-carboxylic acids

The synthesis of some 4H-v-triazolo[1,5-d] [1,3,4]oxadiazin-4-ones is described. They are prepared by the reaction of the corresponding 1-aroylamino-v-triazole-5-carboxylic acids with thionyl chloride in the presence of pyridine. The spectroscopic data of these new compounds are also reported.     

Crystal and molecular structure of 2-acetyl-4-phenyl-5-benzyl-piperidino-5H-1,3,4-selenadiazole

Lensovet Leningrad Technological Institute and A. N. Nesmeyanov Institute of Organometallic Compounds, Russian Academy of Sciences, Moscow. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 2, pp. 180–182, March–April, 1992.     

1,2,3,5-Tetrahydro-4H-1,5-benzodiazepin-4-ones and 1,2,3,4-tetrahydro-5H-1,4-benzodiazepin-5-ones from the reaction of hydrazoic acid on 1,2,3,4-tetrahydroquinolin-4-ones

The Schmidt reaction on 1,2,3,4-telrahydroquinolin-4-ones (1) gave 1,2,3,5-telrahydro-l,5-benzodiazepin-4-ones (II) and 1,2,3,4-tetrahydro-1,4-benzodiazepin-5)-ones(III). The ratio of II and III is dependent upon substituents present on the nitrogen ring atom of the quinolinones.     

The mass spectra of 2-aryl-4-arylidene-oxazol-5-ones,and the related thiazol-5-ones and imidazol-5-ones

Examination of the mass spectra of a series of substituted oxazol-5-ones and other related heterocycles showed no evidence of electron-impact induced isomerism. The electron-impact fragmentations of these compounds were characterized by a single dominant fragmentation process.     

Influence of structure on the circular dichroism of methyl-substituted 1,3,4-tetrahydrobenz[b]azepin-2-ones

The chirooptical properties of methyl-substituted 1,3,4,5-tetrahydrobenz[b]azepin-2-ones have been studied. A considerable increase in the intensity of the Cotton effect (CE) in the 240–250 nm region with an enlargement of the lactam ring has been observed. The sign of this CE for seven-membered benzolactams correlates with the type of conformation of the lactam ring. A change in the nature of the conjugation (passage from lactams of the benzamide type -C₆H₄-CO-NH- to lactams of the anilide type -C₆H₄-NH-CO-) leads to an inversion of the signs of the CEs in the 230–250-nm region.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 97–100, January, 1984.     

Investigations on furopyridines. 10. Synthesis of 4-N-substituted 1H-furo[3,4]pyridin-3-ones

2-Amino or 2-hydrazino derivatives of pyridine or pyridinopyrazole were obtained by amination or hydrazination of 2-chloro-3-cyano-4-methoxy-6-methylpyridine. Acid hydrolysis of these derivatives leads to heterocyclization with formation of 4-amino-1H-furo[3,4-c]pyridines or pyrazolo[3,4-b]pyridine. The possibility to synthesize 4-arylamino-1H-furo[3,4-c]-pyridines from 4-chloro-6-methyl-1H-furo[3,4-c]-pyridine has been shown.V. S. Pustovoit All-Russian Oil-Bearing Crops Research Institute, Krasnodar 350038, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 61–66, January, 1999.     

4-hetarylidene-2-aryloxazol-5-ones

The corresponding 4-hetarylidene-2-aryloxazol-5-ones were synthesized by condensation of furyl- and thienyl-containing aldehydes with hippuric acid and substituted hippuric acids via the Erlenmeyer-Plöchl reaction. The electronic absorption and fluorescence spectra of the compounds in toluene were investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1624–1627, December, 1979.Original article submitted April 17, 1979.     

1,3-Dioxolan-4-ones and 1,3-oxathiolan-5-ones. Configuration of cis and trans isomers

The attempted acid-catalyzed azeotropic removal of water from a mixture containing lactamide and chloral in refluxing toluene lead to the elimination of ammonia; both cis- and trans-5-methyi-2-(trichloromethyl)-1,3-dioxolan-4-one were isolated. A number of 1,3-dioxolan-4-ones and 1,3-oxathiolan-5-ones were obtained by cyclodehydration of aldehydes with α-hydroxy- and α-mercapto-carboxylic acids in the presence of boron trifluoride etherate. Geometric isomers were separated, and their configurations were determined by nuclear magnetic resonance.     

A facile synthesis of 2-substituted-4-(substituted)phenyl-Δ2-1,3,4-oxadiazolin-5-ones

The title compounds, 3, are formed at ambient temperature from 4,4-dimethyl-2-(substituted)-phenylsemicarbazides (1) and carboxylic acid chlorides in the presence of triethylamine. 2-Dimethylamino-4-(substiluted)phenyl-Δ²-1,3,4-oxadiazolin-5-ones are formed from 1 and dialkyl-carbamoyl chlorides at elevated temperature (about 15° ). Acylation of 1 with carboxylic acid anhydrides, also at elevated temperature, is accompanied by loss of dimethylamine from the intermediate l-acyl-4,4-dimethyl-2-(substituted)phenylsemicarbazides, 2, to give 3.     

Hydrazidoyl halides in synthesis of Δ2-1,3,4-selenadiazolin-5-ones

Reaction of hydrazidoyl halides 1-5 with potassium selenocyanate in ethanol produces the corresponding 2,4-disubstituted-5-iminoδ²-1,3,4-selenadiazolines, 9-13 respectively. Nitrosation of the latter yields the N-nitroso derivatives 14-17 , which decompose upon refluxing in xylene to give 2,4-disubstituted Δ²-1,3,4-selenadiazolin-5-ones in good yield. Compounds 9-13 give the respective N-acetyl derivatives 22-26 and N-benzoyl derivatives 27-31 with acetic anhydride and benzoyl chloride in pyridine.