Sterically Crowded Heterocycles. VIII. Preparative Photoisomerization of Some Imidazo[1,2-a]pyridines

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Title:Sterically Crowded Heterocycles. VIII. Preparative Photoisomerization of Some Imidazo[1,2-a]pyridines
Creators:
Kubík, Richard
Böhm, Stanislav
Čejka, Jan
Havlíček, Vladimír
Strnad, Tomáš
Kratochvíl, Bohumil
Kuthan, Josef
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 61, 10, pp. 1473-1488
Uncontrolled Keywords:Photoisomerization, X-Ray structure determination, PM3 method, Imidazo[1,2-<i>a</i>]pyridines

Abstract

UV-Illumination of (<i>Z</i>)-3-(2-phenylimidazo[1,2-<i>a</i>]pyridin-3-yl)-1,3-diphenylprop-2-en-1-one (<strong>1a</strong>) or its 6-methyl and 6-iodo derivatives <strong>1c</strong> and <strong>1g</strong> resulted in minor (<i>E</i>)-isomers <strong>2a</strong>, <strong>2c</strong>, and <strong>2g</strong> and prevailing (<i>E,Z</i>)-mixtures of <i>N</i>-(pyridin-2-yl)-[(3,5-diphenylfuran-2-yl)phenylmethylidene]amines <strong>3a</strong>, <strong>3c</strong>, and <strong>3g</strong> while only corresponding furanoic derivatives <strong>3b</strong> and <strong>3d-3f</strong> were obtained from 5-methyl (<strong>1b</strong>), 7-methyl (<strong>1d</strong>), 8-methyl (<strong>1e</strong>), and 5-phenyl (<strong>1f</strong>) derivatives of the (<i>Z</i>)-ketone <strong>1a</strong>. VIS-Illumination of (<i>Z</i>)-1,3-diphenyl-3-(2-phenylimidazo[1,2-<i>a</i>]benzo[<i>I</i>]quinolin-3-yl)prop-2-en-1-one (<strong>4</strong>) led to <i>N</i>-(benzo[<i>h</i>]quinolin-2-yl)-[(3,5-diphenylfuran-2-yl)phenylmethylidene]amine (<strong>5</strong>). Photoisomers <strong>2a</strong>, <strong>2c</strong>, <strong>2g</strong>, <strong>3a-3g</strong>, and <strong>5</strong> were isolated and the molecular structure of <strong>3c</strong> was X-ray determined. Mechanism of the photoisomerization is discussed using semiempirical quantum chemical calculations and compared with mass spectra of compounds <strong>1a</strong>, <strong>2a</strong>, <strong>3a</strong>, <strong>1g</strong>, <strong>2g</strong>, and <strong>3g</strong>.

Title:Sterically Crowded Heterocycles. VIII. Preparative Photoisomerization of Some Imidazo[1,2-a]pyridines
Creators:
Kubík, Richard
Böhm, Stanislav
Čejka, Jan
Havlíček, Vladimír
Strnad, Tomáš
Kratochvíl, Bohumil
Kuthan, Josef
Uncontrolled Keywords:Photoisomerization, X-Ray structure determination, PM3 method, Imidazo[1,2-<i>a</i>]pyridines
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:61
Number:10
Page Range:pp. 1473-1488
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19961473UNSPECIFIED
ID Code:1051
Item Type:Article
Deposited On:06 Feb 2009 17:06
Last Modified:06 Feb 2009 16:06

Citation

Kubík, Richard; Böhm, Stanislav; Čejka, Jan; Havlíček, Vladimír; Strnad, Tomáš; Kratochvíl, Bohumil; Kuthan, Josef (1996) Sterically Crowded Heterocycles. VIII. Preparative Photoisomerization of Some Imidazo[1,2-a]pyridines. Collection of Czechoslovak Chemical Communications, 61 (10). pp. 1473-1488. ISSN 0010-0765

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