Synthesis of new optically active polycyclic N-heterocycles derived from L- prolinamine

The N-Boc-protected (S)-prolinamine reacts readily with formaldehyde and diverse alphahydroxyimino ketones to give imidazole N-oxides with an enantiomerically pure N-protected (pyrrolidin-2yl)methyl substituent. Subsequent deprotection yields the corresponding NH derivatives. Upon treatment of these products with Ac2O at room temperature, a cascade of reactions leads to optically active tricyclic products. In all these processes, the stereogenic center is preserved. In one case, the bis-heterocyclic imidazole N-oxide was transformed into the corresponding optically active imidazole-2-thione via a sulfurtransfer reaction with 2,2,4,4-tetramethylcyclobutane-1,3-dithione. DOI: https://doi.org/10.1016/j.tetasy.2015.03.005 Posted at the Zurich Open Repository and Archive, University of Zurich ZORA URL: https://doi.org/10.5167/uzh-110500 Accepted Version Originally published at: Wroblewska, Aneta; Mloston, Grzegorz; Heimgartner, Heinz (2015). Synthesis of optically active polycyclic N-heterocycles derived from L-prolinamine. Tetrahedron: Asymmetry, 26(8/9):505-509. DOI: https://doi.org/10.1016/j.tetasy.2015.03.005 Synthesis of new optically active polycyclic N-heterocycles derived from Lprolinamine Aneta Wróblewska, Grzegorz Mlostoń, and Heinz Heimgartner a Universtity of Łódź, Department of Organic and Applied Chemistry, Tamka 12, PL91-403 Łódź, Poland b Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland * Corresponding author. Tel.: +48 42 6655041 (A. W.). E-mail addresses: [email protected] (A. Wróblewska).