| Abstract |
In the present paper we have performed a conformational analysis of the tetrabenzyl ether of the p-tert-butyldihomooxacalix[4]arene by molecular mechanics/molecular dynamics simulations. These calculations indicate that among the six studied conformations, the 1,3-alternate is the thermodynamically most stable conformation, followed by the partial cone A, while the cone is the least stable conformation. Analysis of the energy components of the potential energy shows that these preferences are mainly due to coulombic repulsion interactions between the oxygen atoms as well as to non-bonded steric hindrance between the bulky groups. Molecular dynamics results also indicate that, although all the six conformations are flexible with the phenol rings twisting around from inward to outward pointing, they lie in geometries close to the starting ones and no conformational interconversions were detected. (C) 1999 Elsevier Science B.V. All rights reserved. |
