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Effect of the substituents on the conformational behavior of five-membered rings: Application to the cis- and trans-2,5-dimethoxytetrahydrofuran

✍ Scribed by Ernesto Diez; Jesús Palma; Jesús San-Fabián; Joaquin Guilleme; Angel L. Esteban; Maria P. Galache

Publisher: John Wiley and Sons
Year: 1988
Tongue: English
Weight: 991 KB
Volume: 9
Category: Article
ISSN: 0192-8651
DOI: 10.1002/jcc.540090302

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✦ Synopsis

A model is proposed which assumes that the pseudorotational potential in five-membered rings is given by the combination of contributions from the unsubstituted ring, from the individual substituents and from interactions between pairs of substituents. The application of this model to the potentials calculated by the MM2 force field for the cis and trans-2,5-dimethoxytetrahydrofuran shows that the contributions from the individual substituents explain the main features of the potentials of these disubstituted rings.

The pseudorotational analysis from vicinal proton spin-spin coupling constants 3 J ~~ confirms the realibility of the MM2 potentials.

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