Premium
Conformational preferences for hydroxyl groups in substituted tetrahydropyrans
Author(s) -
Zheng YaJun,
Le Grand Scott M.,
Merz Kenneth M.
Publication year - 1992
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.540130611
Subject(s) - intramolecular force , ab initio , force field (fiction) , scaling , torsion (gastropod) , chemistry , atomic charge , basis set , computational chemistry , ab initio quantum chemistry methods , quantum , electrostatics , physics , quantum mechanics , molecule , density functional theory , stereochemistry , mathematics , geometry , medicine , surgery , organic chemistry
Quantum mechanical ( ab initio and semiempirical) and force field calculations are reported for representative torsion potentials in several tetrahydropyran derivatives. The overall agreement between the various methods is quite good except that the AMBER torsion profiles are sensitive to the choice of atomic point charges. Using electrostatic potential (ESP) derived atomic point charges determined with the STO‐3G basis set we find that AMBER is able to match the best quantum mechanical results quite well. However, when the point charges are derived using the 6‐31G* basis set we find that scaling the intramolecular electrostatic nonbond interactions is necessary. AM1 does not work very well for these compounds when compared to the ab initio methods and, therefore, should only be used in cases when ab initio calculations would be prohibitive. Based upon our results we feel that any force field that makes use of 6‐31G* ESP derived atomic point charges will need to scale intramolecular interactions. Implications of scaling intramolecular interactions to the development of force fields based on 6‐31G* ESP derived atomic point charges are discussed. © 1992 by John Wiley & Sons, Inc.