Related Experiment Video
Updated: Aug 9, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Thermodynamic control synthesis of spiro[oxindole-3,3'-pyrrolines] via 1,4-dipolar cycloaddition utilizing
Areej M Jaber1,2, Jalal A Zahra1, Mustafa M El-Abadelah1
1Chemistry Department, Faculty of Science, The University of Jordan, Amman 11942, Jordan.
Abstract:
A series of novel 2-(quinolin-2-yl)-spiro[oxindole-3,3'-pyrrolines] were synthesized by one-pot three-component reaction involving dimethyl acetylenedicarboxylate, 1-phenylimidazo[1,5-a]quinoline and N-alkylisatins in chloroform at ∼60 °C for 24 h. Structures of these new spiro derivatives were deduced from HRMS and NMR spectral data. A plausible mechanism for the observed thermodynamic control pathway is presented herewith. Interestingly, the spiro adduct, derived from 5-chloro-1-methylisatin, exhibited excellent antiproliferative activity on MCF7, A549 and Hela human cell lines (IC50 ≃ 7 μM).
Related Concept Videos
Cycloaddition Reactions: MO Requirements for Thermal Activation
Cycloaddition Reactions: Overview
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Electrophilic Addition of HX to 1,3-Butadiene: Thermodynamic vs Kinetic Control
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.
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation

![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)