Synthesis of Alkaloids of Galipea officinalis by Alkylation of an α-Amino Nitrile

✍ Scribed by Saurabh Shahane; Fadila Louafi; Julie Moreau; Jean-Pierre Hurvois; Jean-Luc Renaud; Pierre van de Weghe; Thierry Roisnel

• Book ID: 102174040
• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 256 KB
• Volume: 2008
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200800512

✦ Synopsis

Abstract

A new synthetic approach directed towards the synthesis of naturally occurring 2‐alkyl‐tetrahydroquinolines is described. The C–C bonds in the α position relative to the nitrogen atom were formed by the reversal of the polarity of the C=N bond of α‐amino nitrile 6, which was prepared electrochemically from 1‐(phenylethyl)‐tetrahydroquinoline. A NaBH~4~‐mediated reductive decyanation process furnished benzylic amines 16a–d as mixtures of diastereomers (50–60 % de). The catalytic hydrogenolysis of these amines was performed in the presence of Pearlman's catalyst to give the tetrahydroquinolines 17a–d in yields ranging from 70 % to 95 %. Methylation of the free nitrogen atom afforded the title compounds 1–4 in 70–90 % yields.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)