E. A. Gusakov

Synthesis and structure of 3-(tert-butyl)-10,10-dimethyl-10H-indolo[1,2-a]indoline-1,4-dione

33 The structure of products resulting from reaction of 2 methylated azaheterocyclic compounds with 1,2 ben zoquinones depends on the nature of both heterocycle and 1,2 benzoquinone [1–3]. In the series of 2 methyl quinolines [3], 2 methylquinoxalines [4], 2 methyl quinazolinones [5], and 2 methylbenzoxa(thia)zoles [6, 7], the reaction with spatially hindered 1,2 benzo quinone and 3,4,5,6 tetrachloro 1,2 benzoquinone proceeds with expansion of the o quinone ring to give 2 hetaryl substituted 1,3 tropolones. When donor substituent (morpholine or piperidine) is present in the 4 position of 2 methylquinoline, the reaction with 4,6 di tert butyl 3 nitro 1,2 benzoquinone may pro ceed through another route to give derivatives of 2 (quinolin 2 yl) N oxide 2 azabicyclo[3.3.0]octa 2,7 diene 4,6 diones [1, 2]. At the same time, the reaction of 3,5 di (tert butyl) 1,2 benzoquinone 2 with 2 meth ylbenzimidazoles leads to formation of polycyclic iso quinoline derivatives [8], while the reaction of quinone 2 with 1,2,3 trimethylbenzimidazolium salt affords spirane derivative of spatially hindered pyro catechol [9].

Synthesis and structure of 3-arylamino-2-(quinolin-2-yl)tropones

A reaction of substituted 2-(quinolin-2-yl)-1,3-tropolones with POCl3 leads to the new3-chloro-2-(quinolin-2-yl)tropone derivatives. New 2-(4-arylaminoquinolin-2-yl)-3-aryl-aminocyclohepta-2,4,6-trien-1-ones and 2-[4-morpholino(piperidino)quinolin-2-yl]-3-aryl-aminocyclohepta-2,4,6-trien-1-ones were obtained by nucleophilic substitution reaction of the halogen atom in 2-(4-chloroquinolin-2-yl)-3-chlorotropones and 3-chloro-2-[4-morpholino-(piperidino)quinolin-2-yl]tropones. Molecular structures of 3-chloro-2-(quinolin-2-yl)tropone and 3-arylamino-2-(quinolin-2-yl)tropone were established by X-ray diffraction analysis. Energy and structural characteristics of isomers of 3-arylamino-2-(quinolin-2-yl)tropones in the gas phase and in solution were calculated by the density functional theory method (PBE0/6-31G**).

Synthesis and structure of 2-(4′-oxo-3H-quinazolin-2′-yl)-1,3-tropolone

The acid-catalyzed condensation of 2-methyl-4-oxo-3H-quinazolin with 3,5-di(tert-butyl)-1,2-benzoquinone affords 5,7-di(tert-butyl)-2-(4′-oxo-3H-quinazolin-2′-yl)-1,3-tropolone and 2-(3,5-di(tert-butyl)-2-hydroxybenzoyl)-3H-quinazolin-4-one. The molecular structures of 5,7-di(tert-butyl)-2-(4′-oxo-3H-quinazolin-2′-yl)-1,3-tropolone and 2-(3,5-di(tert-butyl)-2-hydroxybenzoyl)-3H-quinazolin-4-one were studied by X-ray diffraction, two-dimensional NMR spectroscopy, and the density functional theory (PBE0/6-311+G**).

Synthesis, structure, and photoluminescence properties of bis[2-(1,3-benzoxazol-2-yl-κN)-4,5-dichloro-3-(ethoxycarbonyl)phenolato-κO]zinc(II)

The structure of bis[2-(1,3-benzoxazol-2-yl-κN)-4,5-dichloro-3-(ethoxycarbonyl)phenolato-κO]-zinc(II) was determined by IR and 1H and 13C NMR spectroscopy, and its structural characteristics were estimated by quantum chemical calculations. The complex showed photoluminescence properties.

Synthesis and structure of 5,7-diisopropyl-2-(quinolin-2-yl)-1,3-tropolone derivatives

A synthetic procedure towards 4,6-diisopropyl-3-nitro-1,2-benzoquinone was elaborated. Based on this benzoquinone, a series of novel 5,7-diisopropyl-2-(quinolin-2-yl)-1,3-tropolones and 5,7diisopropyl-2-(quinolin-2-yl)-4-nitro-1,3-tropolones were derived. Molecular structure of 2-(4-chloro-8-methylquinolin-2-yl)-5,7-diisopropyl-1,3-tropolone was established by X-ray diffraction analysis. Energetic and structural characteristics of isomeric 5,7-diisopropyl-2-(quinolin-2yl)-1,3-tropolones and 5,7-diisopropyl-2-(quinolin-2-yl)-4-nitro-1,3-tropolones in the gas phase and in the polar solvent were calculated by quantum chemistry method (PBE0/6-311+G(d,p)).

Structure, synthesis, and voltammetric investigation of 1-(quinolin-2-yl)-2-(pyran-2-yl)ethane-1,2-dione derivatives

By the XRD analysis the structure was established of 1-(7,8-dimethyl-4-chloroquinolin-2-yl)-2-[3,5-di(tert-butyl)-6-oxo-6H-pyran-2-yl]ethane-1,2-dione formed as a result of the oxidation of 3,5-di(tert-butyl)-6-[(Z)-2-(quinolin-2-yl)-1-hydroxyethen-1-yl]pyran-2-ones. By the cyclic voltammetry the oxidation of 1-(quinolin-2-yl)-2-(pyran-2-yl)ethane-1,2-dione derivatives was shown to proceed in two stages.

Structure of 2-(benzoxazole-2-Yl)- 5,7-di(tert-butyl)-4-nitro-1,3-tropolone

The reaction of 2-methylbenzoxazole with 4,6-di(tert-butyl)-3-nitro-1,2-benzoquinone yields 2-(benzoxazole-2-yl)-5,7-di(tert-butyl)-4-nitro-1,3-tropolone. The structure of 2-(benzoxazole-2-yl)-5,7-di(tert-butyl)-4-nitro-1,3-tropolone is determined by the single crystal X-ray diffraction analysis.

Synthesis and Molecular Structures of (3-Hydroxy, 3-Chloro, 3-Arylamino)-N-acetyl-3-arylaminotropones

The structures of 5,7-di(tert-butyl)-2-(5,8-dimethyl-4-piperidinoquinolin-2-yl)-3-hydroxytropone, 5,7-di(tert-butyl)-3-chloro-2-(5,8-dimethyl-4-piperidinoquinolin-2-yl)tropone, 5,7-di(tert-butyl)- 3-(3,5-dimethylphenylamino)-2-(5,8-dimethyl-4-piperidinoquinolin-2-yl)tropone, and 3-(N-acetyl-3,5- dimethylphenylamino)-5,7-di(tert-butyl)-2-(5,8-dimethyl-4-piperidinoquinolin-2-yl)tropone were determined by X-ray diffraction. These compounds were synthesized through a series of transformations, including the nucleophilic substitution of the chlorine atom by piperidine in the starting 5,7-di(tert-butyl)-2-(4- chloroquinolin-2-yl)-3-hydroxytropone followed by the three-step functionalization of the 3-position in 3-hydroxytropone. The nature of dynamic processes in a solution of N-acetyl-3-arylaminotropone associated with the rotation of the N-acetyl group was revealed by the PCM/PBE0/6-31G(d,p) method.

Synthesis and structure of 4,6-di(tert-butyl)-2-(4-chloro-7,8-dimethylquinolin-2-yl)-7-(piperidin-1-ylmethyl)-1,3-tropolone

The reaction of 4-chloro-2,7,8-trimethylquinoline with 4,6-di(tert-butyl)-3-(piperidin- 1-ylmethyl)-1,2-benzoquinone, which was prepared by the in situ oxidation of 4,6-di(tert- butyl)-3-(piperidin-1-ylmethyl)pyrocatechol with sodium nitrite, gave 4,6-di(tert-butyl)-2- (4-chloro-7,8-dimethylquinolin-2-yl)-7-(piperidin-1-ylmethyl)-1,3-tropolone. Its structure was determined by X-ray diffraction. The energy and structural characteristics of the tauto- mers of this compound in the gas phase and in a polar solution were calculated by quantum chemical methods (PBE0/6-311+G(d,p)).

Synthesis and structural studies of 5,7(4,6)-di(tert-butyl)-2-(6,8-dimethyl-4-chloroquinolin-2-yl)-1,3-tropolones by quantum-chemical methods and two-dimensional correlation NMR spectroscopy

Abstract4,6-Di(tert-butyl)-2-(quinolin-2-yl)-1,3-tropolone (7′) was isolated for the first time from the acid-catalyzed reaction of 2-methyl-substituted nitrogen heterocycles with 1,2-benzoquinones, which proceeds with the expansion of the o-quinone ring to give mainly isomeric 5,7-di(tert-butyl)-2-(quinolin-2-yl)-1,3-tropolone.