Related Experiment Video
Updated: Jun 2, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Synthesis of the stenine ring system from pyrrole
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371. roderick@ntu.edu.sg
Abstract:
The skeleton of the stemona alkaloid, stenine, has been synthesized starting from pyrrole, employing an asymmetric organocatalyzed cyclization, Sonogashira coupling, a diastereoselective intramolecular propargylic Barbier reaction, cyclocarbonylation, and diastereoselective alkene reduction. Modulation of the electron-rich nature of the pyrrole nucleus by employing an α-trifluoroacetyl group is essential. The α-trifluoroacetyl group may be rapidly removed under carefully defined, mild conditions.
Related Concept Videos
Synthesis of α-Substituted Carbonyl Compounds: The Stork Enamine Reaction
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Five-Membered Heterocyclic Aromatic Compounds: Overview
Biosynthesis of Nucleic Acids
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Basicity of Heterocyclic Aromatic Amines
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
