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Z. Naturforsch. 2012,
67b, 1045 – 1055
doi:10.5560/ZNB.2012-0146
2,5-Dihydro-1,3-thiazoles as Scaffolds in the Synthesis of O,N-Diacyl O,N-Acetals in a One-pot Reaction
Institut für Reine und Angewandte Chemie, Carl von Ossietzky Universität Oldenburg, 26111 Oldenburg, Germany
Reprint requests to Professor Jürgen Martens. Fax: +49(0)441 798 3329. E-mail:
juergen.martens@uni-oldenburg.de
Received May 29, 2012 / published online October 8, 2012
Dedicated to Professor Heribert Offermanns on the occasion of his 75th birthday
The Asinger reaction is a very powerful tool to form 2,5-dihydro-1,3-thiazoles in high yields. Treating these heterocyclic imines with acid chlorides followed by adding sodium carboxylates led to a large number of new O,N-diacyl O,N-acetals. Using chiral starting materials, a high diastereoselectivity was observed in several cases. X-Ray structures document the constitution and clarify the relative configuration of the prepared O,N-diacyl O,N-acetals.
Key words: Imines, Acetals, N-Acyliminium Ion, Carboxylates, Stereochemistry