Related Experiment Video
Updated: May 21, 2026

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
HFIP-Promoted One-Pot Synthesis of Indolines and Pyrrolidines
Seung Hoon Lee1, Seung Woo Hong1, Hyung Min Chi1,2
1Department of Chemistry, Pohang University of Science and Technology, Pohang 37673, South Korea.
Abstract:
A practical method for the synthesis of N-heterocycles from readily available amines and alkyl halides in HFIP has been developed. HFIP enables sequential alkylation and cyclization in a one-pot process under acidic conditions. A range of indoline and pyrrolidine derivatives were obtained in moderate to good yields with tolerance toward various functional groups and nitrogen substitution patterns. The synthetic utility of this approach was demonstrated through gram-scale reactions, further transformations of pyrrolidines, and a concise formal synthesis of cephalotaxine.
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