This Account is dedicated to Prof. Dr. Benjamin List (Max-Planck-Institut für Kohlenforschung)
and the Department of Chemistry of Sungkyunkwan University on the occasion of its
70th anniversary.
Abstract
In this Account, we provide an overview of our recent achievements on sustainable
organocatalysis. Our group has unveiled the effectiveness of specific organocatalysts
under various environmentally benign conditions. We have found that N-heterocyclic
carbene and phosphazene superbases exhibit favorable performances in bulk aqueous
reaction environments. In addition, the use of organic superacid catalysts results
in synergistic effects when hydrogen-bond donor catalysts are assembled in aqueous
media. Moreover, we discovered that a neutral organic salt precatalyst can generate
a potent silylium Lewis acid catalyst in situ, specifically under solvent-free conditions.
These innovative, sustainable organocatalytic processes have successfully facilitated
the conversion of raw starting materials into valuable compounds, including sulfur(VI)
fluoride exchange (SuFEx) click hubs and tetrasubstituted carbon centers incorporating
heteroatoms.
1 Introduction
2 Water-Accelerated N-Heterocyclic Carbene (NHC) Catalysis for β-Aminosulfonyl Fluorides
3 Water-Accelerated Phosphazene Superbase Catalysis for β-Sulfidosulfonyl Fluorides
and γ-Geminal Dithioester-Incorporated Sulfonyl Fluorides
4 Water-Accelerated Synergistic Superacid Catalysis for α-Tertiary Amines
5 Solvent-, Metal-, and Purification-Free PPM (parts per million) Neutral Organic
Salt Catalysis for Tertiary Cyanohydrin Derivatives
6 Conclusion
Key words
organocatalysis - sustainable process - on-water - solvent-free - sulfur(VI) fluoride
exchange (SuFEx) - tetrasubstituted carbon centers
