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Z. Naturforsch. 2012,
67b, 907 – 912
doi:10.5560/ZNB.2012-0123
Orthoamides and Iminium Salts LXXXI. Orthoamide Derivatives of 1,3-Dimethylparabanic Acid
Orthoamide und Iminiumsalze, LXXXI. Orthoamid-Derivate der 1,3-Dimethylparabansäure
1 Fakultät Chemie/Organische Chemie, Hochschule Aalen, Beethovenstr. 1, D-73430 Aalen, Germany
2 Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
Reprint requests to Prof. Dr. Willi Kantlehner. Fax: +49(7361)5762250. E-mail:
willi.kantlehner@htw-aalen.de
Received May 7, 2012 / published online September 20, 2012
Herrn Professor Lutz Tietze zum 70. Geburtstag gewidmet
1,3-Dimethyl-5-imino-imidazolidine-2,4-dione (7a) undergoes thiolysis (H2S) to give the corresponding imidazolidine-2,4-dione-5-thione derivative 6. The 5-N-methylimino analogue 7b can be obtained from 7a by methylation. Further methylation of 7b affords the crude iminium salt 8c from which the heterocyclic orthoamide derivatives 10, 11 can be prepared. The heterocyclic amide acetal 9a can be obtained from 7a and dimethyl sulfate in methanol and subsequent addition of sodium methanolate in a one-pot reaction. The aminal ester 10 is converted to the amide acetal 9a on treatment with hydrogen chloride in methanol.
Key words: Orthoamide Derivatives, 1,3-Dimethylparabanic Acid, Iminium Salts