Addition of Organometallic Reagents to Chiral N‐Methoxylactams: Enantioselective Syntheses of Pyrrolidines and Piperidines. Issue 49 (21st October 2013)

• Record Type: Journal Article
• Authors: Jäkel, Mascha; Qu, Jianping; Schnitzer, Tobias; Helmchen, Günter
• Is Part Of: Chemistry. Volume 19:Issue 49(2013)
• Page Start: 16746
• Page End: 16755
• Publication Date: 2013-10-21
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201302735
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>Enantioselective iridium‐catalyzed allylic substitutions were used to prepare <italic>N‐</italic>allyl hydroxamic acid derivatives that were suitable for ring‐closing metathesis, giving <italic>N‐</italic>methoxylactams. Reactions of these derivatives with Grignard or organolithium compounds gave hemiaminals, which could be reduced diastereoselectively via acyliminium intermediates to give <italic>cis</italic>‐piperidines or <italic>cis</italic>‐pyrrolidines with substituents in the 2, 6‐ or 2, 5‐positions, respectively. In addition, compounds with a quaternary carbon center could be synthesized by corresponding reactions with potassium cyanide/AcOH. The procedures were applied in the syntheses of alkaloids (−)‐209D and (+)‐prosophylline.</p> </abstract>