Synthesis and x-ray structural examination of intracomplex boroxadiazolidines

The reaction between acetone monoalkylhydrazones and aldehydes in the presence of boric acid derivatives has given five-membered boron-nitrogen heterocycles, the stability of which is to a large extent dependent on the substituents in the ring. An x-ray structural examination of the boroxadiazolidine (VI) has been carried out.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 178–182, January, 1991.     

Double electron-nuclear resonance of free radical 1,3-diphenyl-1, 4-dihydro-1,2,4-benzotriazin-4-yl

Conclusions The HFS constants for the protons in positions 5–13 of the free radical 1,3-diphenyl-1, 4-dihydro-1,2,4-benzotriazin-4-yl were determined by the DENR method.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 698–699, March, 1984.     

Molecular and Crystal Structure of a Superstable Free Radical, 1,3-Diphenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl

The molecular and crystal structure of a superstable free radical, 1,3-diphenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl, was studied by single crystal X-ray diffraction. The dihedral angle formed by the N-phenyl ring with the heteroring is considerably larger than that formed by the C-phenyl ring; two geminal C-N bonds in the dihydrotriazine ring have virtually equal length. In the crystal, the radical molecules form stacks along the 0b axis due to - interactions of the aromatic fragments of the molecules. The total effect of intermolecular contacts in the crystal leads to formation of a lamellar supramolecular structure.     

Electron spin and electron nuclear double resonances of the stable 1-(4-nitrophenyl)-3-phenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl free radical

The ¹H and ¹⁴N hyperfine structure constants for the stable 1-(4-nitrophenyl)-3-phenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl free radical obtained by the oxidation of 1-(4-nitrophenyl)-3-phenyl-1,4-dihydro-1,2,4-benzotriazine or N-phenylbenzamide 4-nitrophenylhydrazone were determined by the ESR and ¹H electron nuclear double resonance methods.