Complexation Constants and the Template Effect

The template effect has long been accepted prima facie by workers in the crown field because of the obvious relationship between ring size and complexation constant. In fact, Cram stated in 1975 that the templating properties of for preparing crown ethers is well established.. . In fact, the template effect was widely acknowledged and has always received overwhelming support. Nevertheless, few direct comparisons are available in the literature and we have restricted ourselves m this discussion only to direct rather than the large body of presumptive evidence which is currently available. 

Stereochemistry of Carbon Compounds. McGraw Hill, New York 1962, 198 and references therein 

Kawamura, N., Miki, M., Ikeda, I. and Okahara, M. Tetrahedron Letters (1979) 535 

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