title: The Cation-π Interaction in Small-Molecule Catalysis.
abstract: Catalysis by small molecules (≤1000 Da, 10(-9)  m) that are capable of binding and activating substrates through attractive, noncovalent interactions has emerged as an important approach in organic and organometallic chemistry. While the canonical noncovalent interactions, including hydrogen bonding, ion pairing, and π stacking, have become mainstays of catalyst design, the cation-π interaction has been comparatively underutilized in this context since its discovery in the 1980s. However, like a hydrogen bond, the cation-π interaction exhibits a typical binding affinity of several kcal mol(-1) with substantial directionality. These properties render it attractive as a design element for the development of small-molecule catalysts, and in recent years, the catalysis community has begun to take advantage of these features, drawing inspiration from pioneering research in molecular recognition and structural biology. This Review surveys the burgeoning application of the cation-π interaction in catalysis.
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St, Cambridge, MA, 02138, USA.
authors.forename: C Rose
authors.identifier: 0000-0003-3681-819X
authors.initials: CR
authors.lastname: Kennedy
authors.affiliation: Department of Chemistry, University of California, Berkeley, 535 Latimer Hall, Berkeley, CA, 94720, USA.
authors.forename: Song
authors.initials: S
authors.lastname: Lin
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St, Cambridge, MA, 02138, USA. jacobsen@chemistry.harvard.edu.
authors.forename: Eric N
authors.identifier: 0000-0001-7952-3661
authors.initials: EN
authors.lastname: Jacobsen
mesh_terms: D000631:Aminopyridines / Q000737:chemistry; D002384:Catalysis; D002412:Cations / Q000737:chemistry; D061565:Cycloaddition Reaction; D019791:Guanidine / Q000737:chemistry; D006860:Hydrogen Bonding; D058116:Lewis Acids / Q000737:chemistry; D011789:Quantum Theory; D054852:Small Molecule Libraries / Q000737:chemistry*; D013844:Thiazoles / Q000737:chemistry
chemical_list: D000631:Aminopyridines; D002412:Cations; D058116:Lewis Acids; D054852:Small Molecule Libraries; D013844:Thiazoles; D019791:Guanidine
keywords: cation-π interaction; homogeneous catalysis; noncovalent interactions; reaction mechanisms; stereoselective catalysis