Cyansäureester, 27 [1]. Triazino‐benzimidazole aus 2‐Amino‐benzimidazol‐1‐imidsäureestern und carbonylanalogen Verbindungen
Cyanic Acid Esters. 27. Triazino‐benzimidazoles from 2‐Amino‐benzimidazole‐1‐imid‐esters and Carbonyl Analogic Compounds The Cyclocondensation of 2‐amino‐benzimidazole‐1‐imid‐esters with aldehydes, carbonic acid anhydrides and isocyanates has been investigated. With aldehydes in the presence of pipe...
Published in: | Journal für Praktische Chemie |
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Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
1979
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Subjects: | |
Online Access: | http://dx.doi.org/10.1002/prac.19793210305 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fprac.19793210305 https://onlinelibrary.wiley.com/doi/pdf/10.1002/prac.19793210305 |
Summary: | Cyanic Acid Esters. 27. Triazino‐benzimidazoles from 2‐Amino‐benzimidazole‐1‐imid‐esters and Carbonyl Analogic Compounds The Cyclocondensation of 2‐amino‐benzimidazole‐1‐imid‐esters with aldehydes, carbonic acid anhydrides and isocyanates has been investigated. With aldehydes in the presence of piperidine 4‐aryloxy‐1,2‐dihydro‐1,3,5‐triazino[1,2‐a]benzimidazoles 3 and with carbonic acid anhydrides 4‐aryloxy‐1,3,5‐triazino[1,2‐a]benzimidazoles 5 are formed. Isocyanates react with the imid esters to the corresponding 3‐substituted ureas 8 which on heating undergo acyl migration of the carbamoyl group followed by cyclocondensation to 4‐imino‐2‐oxo‐1,2,3,4‐tetrahydro‐1,3,5‐triazino[1,2‐a]benzimidazoles 12 . |
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