2-(3-Acylselenoureido)benzonitriles and 2-(3-Acylselenoureido)thiophene-3-carbonitriles. Preparation, Structure Elucidation, Cyclization and Retrocyclization Reactions

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Title:2-(3-Acylselenoureido)benzonitriles and 2-(3-Acylselenoureido)thiophene-3-carbonitriles. Preparation, Structure Elucidation, Cyclization and Retrocyclization Reactions
Creators:
Šibor, Jiří
Žůrek, Dalimil
Marek, Radek
Kutý, Michal
Humpa, Otakar
Marek, Jaromír
Pazdera, Pavel
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 64, 10, pp. 1673-1695
Uncontrolled Keywords:NMR spectroscopy, multinuclear, 2-Aminobenzonitrile, Fused 1,3-selenazines, Selenium heterocycles, <i>Ab initio</i> calculations, 2-Aminothiophene- 3-carbonitriles, Fused pyrimidines, X-Ray diffraction, Acylselenoureas

Abstract

Synthesis of 2-(3-acylselenoureido)benzonitriles and 2-(3-acylselenoureido)thiophene- 3-carbonitriles <strong>5a</strong>-<strong>5f</strong> by addition of 2-aminonitriles <strong>4a</strong>-<strong>4c</strong> to benzoyl- or 2,2-dimethyl- propanoylisoselenocyanate and their cycloaddition reactions are described. Structures of compounds <strong>5a</strong>-<strong>5f</strong> were supported by CIMS, FTIR, <sup>1</sup>H, <sup>13</sup>C, <sup>77</sup>Se and <sup>15</sup>N NMR spectra. The parameters of <sup>15</sup>N and <sup>77</sup>Se nuclei were obtained from inverse <sup>1</sup>H-X 2D HMBC and GSQMBC correlation experiments at natural abundance. Structure of compound <strong>5b</strong> was confirmed by X-ray analysis. The geometry of <strong>5b</strong> was optimized by <i>ab initio</i> RHF/DZVP quantum chemistry calculation. A very good correlation between the calculation and experimental data was found. The geometry of <strong>5e</strong> was optimized by <i>ab initio</i> DFT/VWN/DZVP quantum chemistry calculation. It was found that title compounds <strong>5a</strong>-<strong>5f</strong> do not undergo isomerization to acylisoselenoureas, in contrast to analogous ester derivatives. Fused 6-imino-6<i>H</i>-1,3- selenazinium salts (chlorides <strong>6a</strong>-<strong>6f</strong>, hydrogensulfates <strong>7a</strong>-<strong>7f</strong> and tetrafluoroborates <strong>8a</strong>-<strong>8f</strong>) were prepared by an acid cyclization of <strong>5a</strong>-<strong>5f</strong>. It was found that neutralization of <strong>6a</strong>-<strong>6f</strong>, <strong>7a</strong>-<strong>7f</strong> and <strong>8a</strong>-<strong>8f</strong> led to their retrocyclization to <strong>5a</strong>-<strong>5f</strong>. Selenoureas <strong>5a</strong>-<strong>5f</strong> with equimolar amounts of methanolic potassium hydroxide afforded potassium salts <strong>9a</strong>-<strong>9f</strong>. Only the salts <strong>9b</strong>, <strong>9c</strong>, <strong>9e</strong> and <strong>9f</strong> of the thiophene series were isolated. Their heating in methanol solution led to deacylation of isoselenoureas <strong>10b</strong> and <strong>10c</strong>. The <i>in situ</i> prepared compounds <strong>9a</strong> and <strong>9d</strong> cyclized and deacylated to 4-aminoquinazoline-2-selenole <strong>11a</strong> under the same conditions. The compounds <strong>5a</strong>-<strong>5f</strong> and <strong>10a</strong>-<strong>10c</strong> cyclized to fused 4-aminopyrimidine-2-selenols <strong>11a</strong>, <strong>11b</strong> and 4-aminopyrimidine-2-selenone <strong>12c</strong> by boiling in methanolic potassium hydroxide solution. <p>

Title:2-(3-Acylselenoureido)benzonitriles and 2-(3-Acylselenoureido)thiophene-3-carbonitriles. Preparation, Structure Elucidation, Cyclization and Retrocyclization Reactions
Creators:
Šibor, Jiří
Žůrek, Dalimil
Marek, Radek
Kutý, Michal
Humpa, Otakar
Marek, Jaromír
Pazdera, Pavel
Uncontrolled Keywords:NMR spectroscopy, multinuclear, 2-Aminobenzonitrile, Fused 1,3-selenazines, Selenium heterocycles, <i>Ab initio</i> calculations, 2-Aminothiophene- 3-carbonitriles, Fused pyrimidines, X-Ray diffraction, Acylselenoureas
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:64
Number:10
Page Range:pp. 1673-1695
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19991673UNSPECIFIED
ID Code:1588
Item Type:Article
Deposited On:06 Feb 2009 17:10
Last Modified:06 Feb 2009 16:10

Citation

Šibor, Jiří; Žůrek, Dalimil; Marek, Radek; Kutý, Michal; Humpa, Otakar; Marek, Jaromír; Pazdera, Pavel (1999) 2-(3-Acylselenoureido)benzonitriles and 2-(3-Acylselenoureido)thiophene-3-carbonitriles. Preparation, Structure Elucidation, Cyclization and Retrocyclization Reactions. Collection of Czechoslovak Chemical Communications, 64 (10). pp. 1673-1695. ISSN 0010-0765

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