| Abstract
| - A systematic conformational study of ω-methoxy methyl esters, CH3O−(CH2)n−COO−CH3 with n= 3 and 4, has been performed using quantum mechanical calculations at the MP2 level.Calculations have been carried out in both gas phase and chloroform solution, a polarizablecontinuum solvation model being used to represent the latter. Results have been compared withthose recently obtained for the analogues ω-hydroxy acids, HO−(CH2)n−COOH with n = 3 and 4.The compounds with n = 3 clearly favor coiled conformations, the population expected for extendedand semiextended conformations being very low. However, for compounds with n = 4 the minimumenergy extended and semiextended structures become considerably more stable. The overall resultsindicate that the conformational preferences of the central aliphatic segment of ω-methoxy methylesters and ω-hydroxy acids are not influenced by the formation of intramolecular O−H···O hydrogenbonds.
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