Diels-Alder reaction, noncovalent catalysis

Kim SP, Leach AG, Honk KN. The origins of noncovalent catalysis of intermolecular Diels-Alder reactions by cyclodextrins, self-assembling capsules, antibodies, and RNAses. J. Org. Chem. 105. 2002 67(12) 4250-4260. 

A self-assembled coordination cage and micelles were found to accelerate Diels-Alder reactions in an aqueous media. The catalysis of Diels-Alder reactions via noncovalent binding by synthetic, protein, and nucleic acid hosts has been surveyed and compared to explore the origin of the noncovalent catalysis. These catalysts consist of binding cavities that form complexes containing both the diene with the dienophile and the reaction occurring in the cavity. The binding requires no formation of covalent bonds and is driven principally by the hydrophobic (or solvophobic) effect. ... 

Wittkopp, A. and Schreiner, PR. (2003) Metal-free, noncovalent catalysis of Diels-Alder reactions by neutral hydrogen bond donors in organic solvents and in water. Chemistry - A European Journal, 9, 407 14. 

Wittkopp, A. Schreiner, P. R. Metal-Free, Noncovalent Catalysis of Diels-Alder Reactions by Neutral Hydrogen Bond Donors in Organic Solvents and in Water. Chem. Eur. J. 2003, 9, 407-414. 

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