A New Asymmetric Synthesis of both Enantiomers of Coniine by 1,2-Addition of RLi/YbCl3 to Aldehyde SAMP Hydrazones

✍ Scribed by Enders, Dieter ;Tiebes, Jörg

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 532 KB
• Volume: 1993
• Category: Article
• ISSN: 0947-3440
• DOI: 10.1002/jlac.199319930131

✦ Synopsis

Abstract

Both enantiomers of the hemlock alkaloid coniine 8 are prepared by asymmetric synthesis in 98% ee using only one enantiomer of the auxiliary. The key step of the synthesis consists in the 1,2‐addition of organoytterbium reagents to aldehyde SAMP hydrazones with virtually complete asymmetric induction, followed by N–N bond cleavage and cyclization.