Dimethylamino-substituted 7H-Benzo[de]pyrazolo[5,1-a]isoquinolin-7-ones and Their Behavior under Vilsmeier-Haack Conditions

The behavior of dimethylamino-substituted 7H-benzo[de]pyrazolo[5,1-a]isoquinoline-7-ones, synthesized for the first time, under conditions of the Vilsmeier-Haack reaction. It has been shown that, on heating with POCl₃ and DMF, they are converted by electrophilic substitution at the position ortho to the dimethylamino group, followed by cyclization of the iminium adduct to a quinazolinium salt. When an acetyl group is present, the Arnold reaction, leading to the formation of a chloroaryl, accompanies the heterocyclization. The rates and proportion of the reaction products depend on the position of the dimethyl groups relative to the pyrazole ring.     

Synthesis and study of organic luminophors containing one or two pyrazoline rings

A series of new organic luminophors with blue and yellow-green fluorescence containing two 1,3,5-triaryl-2-pyrazoline groupings has been obtained and their optical characteristics have been studied. Doubling the molecule of 1,3,5-triphenyl-2-pyrazoline causes a considerable bathochromic effect in the absorption and luminescence and sharply increases the intensity of absorption. The introduction of various bridge groupings weakening or interrupting the chain of conjugation between the two pyrazoline rings leads to a displacement of the absorption and luminescence spectra in the shortwave direction and to a lowering of the relative light yield of photoluminesence.     

Synthesis and spectral-luminescence properties of 2,5-diaryloxazoles that contain a difluoromethylsulfonyl group

A number of 2-(4-difluoromethylsulfonylphenyl)-5-aryloxazoles were synthesized by condensation of 4-difluoromethylsulfonylbenzoyl chloride with -aminomethyl aryl ketones and subsequent cyclodehydration of the resulting amides in sulfuric acid. The spectral-luminescence properties of these products were investigated. The introduction of a difluoromethylsulfonyl group in the 2-phenyl ring of 2,5-diphenyloxazole leads to significant bathochromic and bathofluoric effects and an increase in the quantum yields and photostabilities of the compounds obtained. Complication of the structure of the 5-phenyl ring is accompanied by a further long-wave shift of the absorption and fluorescence spectra without substantial changes in the fluorescence quantum yields. A positive solvatochromism effect is displayed distinctly in the fluorescence spectra of the compounds obtained on passing to polar solvents; this effect increases markedly as the polarity of the solvent increases.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1042–1046, August, 1982.     

Anhydrides and phenylimides of 4-(5-aryl-2-oxazolyl)naphthalic acids

A number of 4-(5-aryl-2-oxazolyl)naphthalic anhydrides were obtained by condensation of 4-chloroformylnaphthalic anhydride with -aminomethyl aryl ketones and subsequent cyclization of the resulting amides; N-phenylimides were obtained from the anhydrides by reaction with aniline. The relationship between the structures of the substances obtained and their UV and luminescence spectra was investigated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1331–1333, October, 1973.     

Synthesis and spectral-luminescence properties of hetarylethylene derivatives of 2,5-diphenyloxazole and 2,5-diphenyl-1,3,4-oxadiazole

A number of new organic luminophores was synthesized by PO olefination from 2- (4-bromomethylphenyl)-5-phenyloxazole and -1,3,4-oxadiazole and various heterocyclic aldehydes that contain a furan ring. The absorption and fluorescence spectra of the products in toluene, as well as their scintillation characteristics, were measured. The effect of the electronic nature of the substituents on the spectral-luminescence properties of the luminophores is discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 617–621, May, 1982.     

Halogen-substituted 2-(2′-arenesulfonylaminophenyl)-4h-1,3-benzoxaz-4-ones

Chloro- and bromo-substituted 2-(2-tosylaminophenyl)-4H-1,3-benzoxaz-4-ones and 2-(2-tosylaminophenyl)-4H-naphtho[2,3-d]-1,3-oxaz-4-ones, their absorption spectra at room temperature, and their luminescence spectra at 77 deg K are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1597–1601, December, 1970.     

Proton scattering on a 15N nucleus in diffraction theory

Within the Glauber diffraction theory, the differential scattering cross section of protons on the ¹⁵N nucleus was calculated at energies of 0.6 and 1.0 GeV. The ¹⁵N wave function in the shell model was used. The dependence of the differential cross section on the nucleus structure and the contribution of single and double collisions in the multiple scattering operator was taken into account.     

Synthesis of arylethylene derivatives of 2, 5-diphenyl-1, 3, 4-oxadiazole

The synthesis of arylethylene derivatives of 2,5-diphenyl-1,3,4-oxadiazole by the Wittig reaction from 2-(p-bromomethylphenyl)-5-phenyl-1,3,4-oxadiazole and aromatic aldehydes is described. The compounds obtained fluoresce strongly on irradiation with UV light.