Related Experiment Video
Updated: Aug 29, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Regiodivergent Asymmetric Pyridinium Additions: Mechanistic Insight and Synthetic Applications
Thiago A Grigolo1, Joel M Smith1
1Department of Chemistry and Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, 32306 Florida, USA.
Abstract:
A practical protocol for the first regiodivergent asymmetric addition of aryl and alkenyl organometallic reagents to substituted N-alkyl pyridinium heterocycles is described. The couplings proceed with high regiochemical and stereochemical selectivities, and provide access to chiral 1,2,3- and 1,3,4-trisubstituted dihydropyridine products, controlled by judicious choice of nitrogen activating agent. To this end, a correlation was found between the parameterized size of the activating group and the C2/C4 regioselectivity in the couplings. The utility of the described chemistry was demonstrated in two concise asymmetric syntheses of (+)-N-methylaspidospermidine and (-)-paroxetine.
More Related Videos
10:17Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
09:58Metal-free Synthesis of Ynones from Acyl Chlorides and Potassium Alkynyltrifluoroborate Salts
Published on: February 24, 2015
Related Concept Videos
Cycloaddition Reactions: Overview
Cycloaddition Reactions: MO Requirements for Thermal Activation
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction
Pericyclic Reactions: Introduction
Pericyclic reactions can be classified into three categories: electrocyclic reactions, cycloaddition reactions, and sigmatropic rearrangements. Electrocyclic reactions and sigmatropic...
Radical Anti-Markovnikov Addition to Alkenes: Overview
Regioselectivity of Electrophilic Additions-Peroxide Effect