Izvestiya of Saratov University.

Chemistry. Biology. Ecology

ISSN 1816-9775 (Print)
ISSN 2541-8971 (Online)


Full text:
(downloads: 144)
Language: 
Russian
Heading: 
Article type: 
Article

Qualitative and Quantitative Estimation of Intramolocular Hydrogenic Communication in a Row of Orto-R-phenyl-substituted Tetrazolohexahydroquinazolines

Autors: 
Vasilkova Natalia Olegovna, Saratov State University
Aniskov Alexandr Andreevich, Saratov State University
Krivenko Adel P., Saratov State University
Abstract: 

The onе-pot interaction of C-aminotetrazole, cyclohexanone and o-R-benzaldehydes (in contrast to unsubstituted benzaldehyde benzaldehyde) leads to the formation of additionally linear tetrazohexahydroquinazolines, their isomers with an angular articulation of the rings. The appearance of isomers with angular articulation of the rings can be explained by the total influence of the spatial and electronic effects, and the influence of the low-energy interaction by the type of hydrogen binding NH ··R (VVS) can not be ruled out. This is confirmed by the NMR shift in the 1 H spectrum of the NH-proton singlet to a weak or strong field compared to tetrazohexahydroquinazoline, which is unsubstituted in the benzene ring. Qualitative and quantitative estimation of air force is given on the example of ortho-nitrophenyl-substituted tetrazohexahydroquinazoline. The concentration dependence of the absorption bands of stretching vibrations of the NH-bond in IR spectra in acetonitrile solution made it possible to record the air force and the MBS, the latter band disappearing upon dilution of the test solution. A similar picture was not observed for unsubstituted tetrazohexahydroquinazoline. With the help of quantum chemical calculations, a rapprochement of the nitro group and the hydrogen atom of the NH-group of the pyrimidine ring with an intermolecular depletion of 2.24 A is determined, sufficient for the formation of the air force and its energy (12 kJ/ mol). Comparative data are given for an analogue of the tetrazolohexahydroquinazoline, which is unsubstituted in the ortho-position of the benzene ring. The obtained results allowed to substantiate the scheme for the formation of positional isomers of ortho-R-phenyltetrazolohexahydroquinazolines.

Reference: 

1. Пат. RU 2424242 C2, C07D 487/04. Азолопиримидины в качестве ингибиторов активности каннабиноидного рецептора. 

2. Raju Ch., Kalaipriya M., Uma R., Sridhar R., Ramakrishna S. Pyridinium Trifl uoro Acetate Mediated Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones and Tetrazolo[1,5-a] pyrimidine-6-carboxylates // Current Chemistry Letters. 2012. Vol. 1. Р. 27–34. 

3. Гейн В. Л., Замараева Т. М., Носова Н. В., Вахрин М. И., Слепухин П. А. Синтез 7-арил-N-метил(N,N-диэтил)- 5-метил-4,7-дигидротетразоло[1,5-а]пиримидин- 6-карбоксамидов // Журн. орг. химии. 2012. Т. 48, вып. 3. С. 422–425. 

4. Чебанов В. А., Десенко С. М. Многокомпонентные реакции гетероциклизации с управляемой селективностью // Химия гетероциклических соединений. 2012. № 4. С. 607–625. 

5. Василькова Н. О., Кривенько А. П. Трёхкомпонентный синтез орто-фенилзамещенных тетразологексагидро- хиназолинов. Влияние орто-эффекта на соотношение позиционных изомеров // Международное научное издание SWorld : сб. науч. тр. Одесса, 2015. Т. 25, вып. 1. С. 4–7.