Related Experiment Video
Updated: Apr 11, 2026

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
A Michael Equilibration Model To Control Site Selectivity in the Condensation toward Aminopyrazoles
Daniel R Fandrick1, Sanjit Sanyal1, Joseph Kaloko1
1†Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, P.O. Box 368, Ridgefield, Connecticut 06877-0368, United States.
Abstract:
A Michael equilibration model is presented to provide for site-selective pyrazole condensations between alkoxyacrylonitriles and hydrazines. Both pyrazole isomers were accessed with high selectivity by employment of kinetically or thermodynamically controlled conditions. Substrate scope and identification of Michael intermediates, as well as competitive pathways, support the presented mechanistic proposal. Sandmeyer derivatization provided site-selective access to fully substituted pyrazoles.
More Related Videos
Related Concept Videos
Conjugate Addition of Enolates: Michael Addition
Basicity of Heterocyclic Aromatic Amines
Antifungal Agents
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Preparation of 1° Amines: Azide Synthesis
Azide ions act as good nucleophiles and react with unhindered alkyl halides to form alkyl azides. Alkyl azides do not participate in further nucleophilic substitution reactions, thereby eliminating the chances of polyalkylated products. Alkyl azides are reduced by hydride-based reducing agents, like lithium aluminum...
Nucleophilic Aromatic Substitution: Elimination–Addition

