I. E. Pokrovskaya

Spin-trapping study of radical products of photolysis of 1,2-dihydroquinolines

Conclusions1.Radicals formed during the photolysis of dihydroquinolines react with spin traps at two reactive centers.2.The constant of the interaction of the aminyl radical of 2,2,4,6-tetramethyl-1,2,-dihydroquinoline with C-phenyl-N-tert-butylnitrone has been determined.

The synthesis of hydroxy, acyloxy, oxo, N-oxide oxo, and morpholino derivatives of hydrogenated quinolines and study of their radical analogs by ESR

Conclusions1.The hydroxy, acyloxy, oxo, N-oxide oxo, and morpholino-oxo derivatives of 2,2,4-trimethyl-substituted 1,2,-di-and 1,2,3,4-tetrahydroquinolines have been synthesized. Their structure was confirmed by the IR and PMR spectra.2.The radicals formed during photolysis of a toluene solution of 2,2,4-trimethyl-8-hydroxy-1,2,3,4-tetrahydroquinoline as well as by oxidation of the acyl derivatives of 2,2,4-trimethyl-6-hydroxy-1,2,3,4-tetrahydroquinoline by meta-chloroperbenzoic acid were recorded and studied by the ESR method.

Crystal and molecular structure of the monohydrate of 2,3-[4′-(N-phenylhydroxylamino)]benzo-15-crown-5

The value of hydroxamic acids as ligands in complexes with metals results from the bidentate nature of the hydroxamido group (HH); -N(OH)-C(=O)-. A modification in the composition of these acids (the introduction of various Nand C-substituents) reveals the role of electron and steric factors which influence the conformation of HH and the stability of the complexes. We have previously determined the structure of N-(3-nitrocinnamoyl)-N-(2-chlorophenyl)hydroxylamine [i] (NO2C6H4-CH=CH-C(O)-N(OH)-~H4CI), a hydroxamic acid, containing

X-ray diffraction structural analysis of 2, 2, 4-trimethyl-substituted 6-hydroxy-1, 2-dihydro- and 6-oxo-2, 6-dihydroquinolines

i. A.O. Litinskii, Zh. Strukt. Khim., 23, 40 (1982). 2. A.O. Litinskii, Zh. Strukt. Khim., 2-3, 48 (1982). 3. I.P. Zakharov, A. O. Litinskii, and L.-M. Z. Balyavichyus, Teor. Eksp. Khim., 18, 16 (1982). 4. T. Penkalya, Outline of Crystal Chemistry [in Russian], Izd. Khimiya, Leningrad (1974). 5. G. Krebs, Fundamentals of the Crystal Chemistry of Inorganic Compounds [Russian trans!lation], Izd. Mir, Moscow (1971). 6. J. Slater, Dielectrics, Semiconductors, and Metals [Russian translation], Izd. Mir, Moscow (1969).

Crystal structure of 2-tert-butyldiphenylamine

During UV irradiation of benzoquinones and diphenoquinones in the presence of diphenylamine (DPA) or its tert-butyl deriatives there is a photoreduction of the carbonyl group. As a result of transfer of an H atom there are formed neutral radicals, stable under low-temperature photolysis, which join into radical pairs of various types [i, 2], the structure of which is assumed to be identical with the structure of the corresponding molecular complexes. Conclusions on the structure of the radicals and supposed complexes are based purely on ESR, and there are no x-ray structural data for these complexes and their donor components tertbutyl-substituted DPA. We have therefore made an x-ray structural investigation of 2-tertbutyldiphenylamine (I).

Primary photophysical and photochemical processes in solutions of 1,2,3,4-tetrahydkoquinolines

Conclusions1.Photoexcitation of solutions of 1,2,3,4-tetrahydroquinolines in the long-wave absorption band results in dissociation of the N-H bond in the lower triplet electron-excited state and the formation of aminyl radicals.2.In photoirradiation of 1,2,3,4-tetrahydroquinolines in the short-wave absorption band, dissociation of the N-H bond from higher electron-excited states takes place.

Synthesis and properties of derivatives of 2,2,4-trimethyl-substituted quinolines and some of their analogs

Conclusions1.We synthesized the 6-hydroxy-7-t-Bu-, 6-oxo-, and 8-N-morpholyl-6-oxo derivatives of the 2,2,4-trimethyl-substituted 1,2-di- and 1,2,3,4-tetrahydroquinolines, and also the 2,2,4,5,7,7, 9-heptamethy1-1,2,7,8-tetra- and 1,2,3,4,5,6,7,8-octahydro-1,8-diazoanthracenes.2.The EPR method was used to record and study the radical that is formed by the oxidation of a toluene solution of 2,2,4,5,7,7,9-heptamethyl-1,2,3,4,5,6,7,8-octahydro-1,8-diazoanthracene with m-chloroperbenzoic acid.3.It was shown that 2,2,4-trimethyl-8-hydroxy-1,2,3,4-tetrahydroquinoline reacts with Fe3+ ions.

Nature of the radicals formed in the photolysis of 2,2,4-trimethyl-1,2-dihydroquinolin-6-ol

Conclusions1.The photolysis of 2,2,4-trimethyl-1,2-dihydroquinolin-6-ols leads to the formation of aminyl radicals, the main route of disappearance of which is dimerization.2.The appearance of nitroxyl radicals in the photolysis of 2,2,4-trimethyl-1,2-dihydroquinolin-6-ol in the presence of O2 is a side reaction taking place with a quantum yield ≤ 0.001.