Reaction of dichlorocarbene with 2,3-dihydro-5,6-dimethyl-1,4-oxathiin and 2,3-dihydro-5,6-dimethyl-1,4-dithiin

Dichlorocarbene, generated from ethyl trichloroacetate and sodium ethoxide, reacts with 2,3-dimethyl-5,6-dihydro-1,4-oxathiin to give 7,7-dichloro-1,6-dimethyl-2-oxa-5-thiabicyclo[4,1,0]heptane, and with 2,3-dimethyl-5,6-dihydro-1,4-dithiin to give 6-chloro-2,3-dihydro-7-methyl 5-methylene-5(H)-1,4-dithiepin. Both products were oxidised to the corresponding sulfone.     

Reaction of 2,3-dihydro-4-phenyl-1H-1,5-benzodiazepinethione-2 with acetylhydrazine

Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, p. 1430, October, 1991.     

Electrooxidation of 2,3-dihydro-1H-1,3,2-diazaphospholes

Electrooxidation of 2-R-1,3-dibutyl-4,5-dimethyl-2,3-dihydro-1H-1,3,2-diazaphospholes with tri- and tetracoordinated phosphorus atoms were studied. Reversible one-electron oxidation gives radical cations at potentials of −0.37 to +0.36 V. Magnetic parameters of the radical cations were measured. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1522–1524, August, 1998.     

Reaction of 2-methyl-5,6-dihydro-2H-pyran with dichlorocarbene

Upon treatment of 2-methyl-5,6-dihydro-2H-pyran with dichlorocarbene there are formed products of addition to the double bond and insertion at the C-H bond giving cis- and trans-7,7-dichloro-2-methyl-3-oxabicyclo[4.1.0]heptane and 2-dichloromethyl-2-methyl-5,6-dihydro-2H-pyran.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 190–191, February, 1986.     

Aromatic derivatives of 2,3-dihydro-1H-1,5-benzodiazepine

The formation of 2,2,4-trisubstituted 2,3-dihydro-1H-1,5-benzodiazepines in the reactions of acetylarenes with 4-ethoxy- and 3,5-dimethyl-1,2-phenylenediamine was studied. The effect of the substituents on the individual stages of the reactions is discussed. A quantum-chemical calculation of the relative nucleophilicity of 1,2-phenylenediamine, 2,3-diaminopyridine, and 3,4-diaminofurazan was undertaken.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 370–375, March, 1987.     

Azomethine imines in the reactions of dichlorocarbene with mono- and 1,2-disubstituted hydrazines

Oxidation of phenylhydrazine and 1,2-disubstituted hydrazines with dichlorocarbene afforded the corresponding diazenes and hydrazones with the intermediate formation of the unstable azomethine imines, which were determined by their cycloaddition to dimethyl malcate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1489–1492, June, 1996.     

Synthesis of 5-amino-2,3-dihydro-1H-1,4-benzodiazepines

A number of 5-amino-2,3-dihydro-lH-1,4-benzodiazepines (II) have been prepared from the reaction of 5-methylmercapto-2,3-dihydro-1H-1,4-benzodiazepine (I) with amines. Another alternate approach based on the cyclodehydration of the ureic compounds (IV) was unsuccessful. The synthesis of I was accomplished by methylation of the 1,2,3,4-tetrahydro-5H-5-thioxo-1,4-benzodiazepine (VI) with dimethyl sulfate in methanol-dioxane. Another attempted method for the synthesis of I is also presented. J. Heterocyclic Chem., 14, 985 (1977)     

Mass spectra of 1H-2,3-dihydro-1,4-benzodiazepine-2-thiones

The mass-spectrometric fragmentation of 1H-2,3-dihydro-1,4-benzodiazepine-2-thiones differs substantially from the fragmentation of the corresponding oxo derivatives with respect to the presence of [M - HCN]⁺ and [M - SH]⁺ ions. This is due to the tautomeric transformation of the molecular ions of the thiones to enethiol and eniminothiol tautomeric forms. The approximate percentages of each of the tautomeric forms were estimated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1412–1417, October, 1976.     

Synthesis and properties of 2,2,4-trisubstituted 2,3-dihydro-1H-1,5-benzodiazepines

General conditions for the condensation of acetylarenes with o-phenylenediamine hydrochloride, leading to the formation of 2,4-diaryl-2-methyl-2,3-dihydro-1H-1,5-benzodiazepines, have been worked out. It has been shown that this reaction is an equilibrium one, that the equilibrium is extremely sensitive to the amount of water in the reaction medium, and that the process takes place with the formation of bisazomethines as intermediates. The UV, IR, and PMR spectra and the dipole moments of the heterocyclic compounds obtained are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 126–131, January, 1984.     

Synthesis and mass spectra of 2,3-dihydro-1H-1,5-benzodiazepine-2-thiones

2,3-Dihydro-1H-1,5-benzodiazepine-2-thiones and their N-methyl and S-methyl derivatives were synthesized. It was demonstrated by means of the IR, UV, PMR, and mass spectra that in solutions with different polarities 1,5-benzodiazepine-2-thiones exist primarily in the thione form; the thione and enamino-thiol forms are the most probable forms in the gas phase.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 396–400, March, 1990.     

Crystal and molecular structure of 2,4-diphenyl-2,3-dihydro-1H-1,5-benzodiazepine

A. Mickiewic Poznan University. A. M. Gor'kii Khar'kov State University. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 3, pp. 187–190, May–June, 1989.     

New aspects of the chemistry of 2,3-dihydro-1H-1,5-benzodiazepine

Under basic catalysis conditions the reaction of 4- and 4'-substituted chalcones with o-phenylenediamine leads to 2,3-dihydro-2,4-diaryl-1H-1,5-benzodiazepines; -amino adducts, the ability of which to undergo intramolecular condensation increases as the basicity of the catalyst is increased, are formed as intermediates. A different pathway for the process (the formation of an azomethine) is observed in the reaction with cinnamaldehyde. It is concluded that conformational factors play a primary role in the direction of the reaction.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 697–700, May, 1980.     

Synthesis of 4-Pyridyl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones

4-Pyridyl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones were obtained by the condensation of ethyl nicotinoyl- or isonicotinoylacetates with o-phenylenediamine. Alkylation of the pyridylbenzodiazepinones with ethyl iodide under phase-transfer catalysis conditions occurred at the amide nitrogen of the heterocycle, whereas in nitromethane it occurred at the nitrogen of the pyridine substituent. Bromination with N-bromosuccinimide occurred at position 3 of the heterocycle. Pyridyldibenzodiazepinones underwent thermal rearrangement to derivatives of vinylbenzimidazole.     

Formylation of 4-aryl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones

The formylation of 8-chloro- and 8-methoxy-4-phenyl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones with the Vilsmeier reagent leads to 3-dimethylaminomethylene derivatives which, in the case of the 8-chloro derivative, have been converted by hydrolysis in acetic acid into 8-chloro-3-formyl-4-phenyl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones.Translated from Khimiya Geterotsiklicheskaya Soedinenii, No. 9, pp. 1262–1265, September, 1984.     

Synthesis of 4-styryl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones

4-Styryl-2,3-dihydro-1H-1,5-benzodiazepin-2-ones were synthesized and their structure was established by means of PMR spectra and mass spectroscopy.Dnepropetrovsk State University Named in Honor of 300th Anniversary of the Reunion of Ukraina and Russia, Dnepropetrovsk 320625. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1560–1562, November, 1987.     

Nitration of 8-substituted 2,3-dihydro-1H-1,5-benzodiazepin-2-ones

The nitration of a number of 8-R-4-R-2,3-dihydro-1H-1,5-benzodiazepin-2-ones with substituents in the diazepin (4-R=CH₃, C₆H₅, and C₆H₄OCH₃-p) and benzene (8-R=Cl, Br) rings takes place in the 7 position. The presence in the benzene ring of a strong electron-donor substituent (methoxy group), by determining the direction of electrophilic substitution in the ortho position with respect to it, leads to the formation of 7- and 9-nitro isomers in a ratio of 43.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 551–554, April, 1978.     

Reactions of 2,3-bishydroxyimino-1,2,3,4-tetrahydro-quinoxalines and 2,3-bishydroxyimino-2,3-dihydro-4H-1,4-benzoxazines with ethyl chloroformate

Bishydroxyiminoquinoxalines 3a-b react with ethyl chloroformate 4 to afford the furazano[3,4-b]quinoxalines 5a-b . Bishydroxyiminobenzoxazines 6a-c on treatment with 4 are converted into the fused oxadiazolones 7a-c and 8a-c along with the bisethoxycarbonyloxyimino-derivatives 9a-c . From the reactions of 4 with the oxanilide dioximes 12a-c compounds 13a-c and 14a-b are obtained.     

Reactions of 2-allylthiobenzimidazole, -oxazole, -thiazole, and the isomeric thiones with dichlorocarbene

The reactions of 2-allylthiobenzimidazole, -oxazole, and-thiazole, and the thiones formed from them on heating, with dichlorocarbene have been investigated under phase transfer catalysis conditions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 243–248, February, 2000.