Concave pyridines for bifunctional acid-base catalysis

European Journal of Organic Chemistry

Volumn , Issue 6, 2007, Pages 972-980

  Liebig, Timo ^a   Abbass, Michael ^a   Lüning, Ulrich ^a  

^a UNIVERSITY OF KIEL   (Germany)

Author keywords

Acid catalysis; Base catalysis; Bifunctional catalysis; Heterocycles; Macrocycles; Supramolecular chemistry

Indexed keywords

EID: 34250654582     PISSN: 1434193X     EISSN: 10990690     Source Type: Journal    
DOI: 10.1002/ejoc.200600842     Document Type: Article

References (19)

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14. Single hydrogen bonds are weak interactions, the typical bond energy is 10 to 30 kJ/mol. Therefore, at room temperature in solution, only a fraction of hydrogen-bond donor and acceptors will exist in the hydrogen bonded state. In contrast to the intermolecular formation of a single hydrogen bond, intramolecular hydrogen bonds are formed to a much larger extent due to the vicinity of hydrogen-bond donor and hydrogen-bond acceptor. The "effective concentration" of both centers is high in the intramolecular case.
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