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Highly Stereoselective Total Syntheses of (±)-Chelidonine and of (±)-Norchelidonine by an Intramolecular o-Quinodimethane/Nitrostyrene-Cycloaddition

✍ Scribed by Wolfgang Oppolzer; Christian Robbiani

Publisher
John Wiley and Sons
Year
1983
Tongue
German
Weight
610 KB
Volume
66
Category
Article
ISSN
0018-019X

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✦ Synopsis

Abstract

Conversion of 2‐bromomethylstyrene 22 and benzocyclobutenyl carbamate 28 to the benzophenanthridine alkaloids (±)‐chelidonine (1, five steps, 25% from 28) and to (±)‐norchelidonine (2, six steps, 24% from 28) are described. The key step 29 → 31 involves a highly regio‐ and stereocontrolled intramolecular Diels‐Alder reaction of the (E)‐quinodimethane 30.

📜 SIMILAR VOLUMES

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