Generation and Reaction of Ammonium Ylides in Basic Two-Phase Systems

✍ Scribed by Anna Kowalkowska; Dorota Suchołbiak; Andrzej Jończyk

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 154 KB
• Volume: 2005
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200400556

✦ Synopsis

Abstract

Reaction of the quaternary ammonium salts 2a–i with electrophilic alkenes 3, active alkylating agents 7 or aromatic aldehydes 11, carried out in basic two‐phase systems A–D, afforded cyclopropanes 4, cyanoalkenes 8 or cyanooxiranes 12 respectively, via the corresponding ammonium ylides 2^+^ ^–^. The method is very simple, and gives cyclopropanes 4 and cyanoalkenes 8 in high yield. Under similar conditions, 1‐cyanodienes 8aa,ba were cyclopropanated at the γ,δ‐double bond with formation of vinylcyclopropanes 9a,b. The stereochemistry of the prepared cyclopropanes was elucidated from literature, ^1^H NMR spectroscopic data, NOE experiments or X‐ray single crystal analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)