Thermal transformations of 2H-benzimidazole 1,3-dioxides

Thermal transformations of 2H-benzimidazole 1,3-dioxides Full article

Journal

Russian Chemical Bulletin
ISSN: 1066-5285 , E-ISSN: 1573-9171

Output data

Year: 2011, Volume: 60, Number: 8, Pages: 1723-1728 Pages count : DOI: 10.1007/s11172-011-0257-x

Tags

2H-benzimidazoles; 2,1,4-benzoxadiazines; heterocyclic N-oxides; rearrangements; phototransformation; oxidation

Authors

Samsonov V. A. ¹ , Bagryanskaya I. Yu ¹ , Gatilov Yu V. ¹ , Savel'ev V. A. ¹

Affiliations

1	(Данные Web of science) Russian Acad Sci, NN Vorozhtsov Novosibirsk Inst Organ Chem, Siberian Branch, Novosibirsk 630090, Russia

Thermal transformations of 2H-benzimidazole 1,3-dioxides represented by spiro[2H-benz-imidazole-2,1'-cyclohexane] 1,3-dioxide and its 5-nitro derivative were studied. Their heating resulted in reversible isomerization to spiro[3H-[2,1,4]benzoxadiazine-3,1'-cyclohexane] 4-oxides. More prolonged heating of 2H-benzimidazole 1,3-dioxides caused sequential elimination of the first and then (at higher temperature) the second N-oxide oxygen atom to form 2H-benzimidazole derivatives, which upon further heating were transformed to 7,8,9,10-tetrahydro-6H-azepino[1,2-a]benzimidazoles. A scheme of the process was suggested, which described the experimental data obtained. Spiro[3H-[2,1,4]benzoxadiazine-3,1'-cyclohexane] 4-oxides on exposure to the sunlight were quantitatively transformed to 2H-benzimidazole 1,3-dioxides.

Samsonov V.A. , Bagryanskaya I.Y. , Gatilov Y.V. , Savel'ev V.A.
Thermal transformations of 2H-benzimidazole 1,3-dioxides
Russian Chemical Bulletin. 2011. V.60. N8. P.1723-1728. DOI: 10.1007/s11172-011-0257-x WOS Scopus РИНЦ

Published print:	Aug 1, 2011
Published online:	May 29, 2012

Web of science	WOS:000304617900032
Scopus	2-s2.0-84864546127
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