ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
A PCILO study of the hydrogen-bond of linear ethers and crown ethers with phenol
M. Omastová, J. Mlýnek, and A. Romanov
Polymer Institute, Centre for Chemical Research,
Slovak Academy of Sciences, CS-842 36 Bratislava
Abstract: The PCILO method was used for calculation of interaction energies of
phenol with linear and crown ethers. The geometry of all interacting molecules was at first completely optimized.
The linear ethers represented systems of the structure R—(CH2—CH2—0)x—R with the number of oxygen atoms x = 1,2, 3,4, 6 and R =—CH3,—CH2—CH3. 1,4-Dioxan, 12-crown-4, and 18-crown-6 were
calculated as cyclic ethers.
Association energies were shown to be almost independent of the number
of oxygen atoms in an ether molecule. This holds for both linear and cyclic
ethers. Differences in association energies of linear and cyclic ethers are
small (to 2kJmol-1).
As a whole, the hydrogen bond between associates may be considered as
weak; it follows from the value of the energy (about — 20 k J mol-1) and
from the — О — О — distance, which is only little smaller than a sum of van
der Waals radii of oxygen atoms.
Full paper in Portable Document Format: 422a205.pdf
Chemical Papers 42 (2) 205–212 (1988)
Tuesday, November 12, 2019