Related Experiment Video
Updated: Sep 30, 2026

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines
Published on: January 3, 2018
A new approach to (-)-swainsonine by ruthenium-catalyzed ring rearrangement
Nicole Buschmann1, Anke Rückert, Siegfried Blechert
1Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, Germany.
Abstract:
A new enantioselective synthesis of the idolizidine alkaloid (-)-swainsonine 1 in 40% overall yield starting from the known oxazolidinone 6 is described. Throughout the synthesis, the high efficiency of metal-catalyzed reactions is illustrated. The key step is a new ruthenium-catalyzed metathesis rearrangement reaction. In this ring-closing/ring-opening tandem process, stereocenters are transferred from a ring to the olefinic side chain of the formed heterocycle. The metathesis precursor was obtained by palladium-catalyzed desymmetrization of cyclopentenediol. The synthesis was completed by functionalization of the terminal double bond, cyclization of the second ring, and diastereoselective dihydroxylation.
Related Concept Videos
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Nucleophilic Aromatic Substitution: Addition–Elimination (SNAr)
The reaction begins with an attack of the nucleophile on the carbon that holds the leaving group. This results in the delocalization of the π electrons over the ring carbons. The resonance interaction between the...
[3,3] Sigmatropic Rearrangement of Allyl Vinyl Ethers: Claisen Rearrangement
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
[3,3] Sigmatropic Rearrangement of 1,5-Dienes: Cope Rearrangement
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo, or cyano...

