Experimental and DFT investigation of structure and IR spectra of H-bonded associates of p-(3-carboxy-1-adamantyl)thiacalix[4]arene

• Published in: Journal of molecular modeling Vol. 27; no. 5; p. 135
• Main Authors: Furer, Victor L., Potapova, Ludmila I., Chachkov, Denis V., Vatsouro, Ivan M., Kovalev, Vladimir V., Shokova, Elvira A., Kovalenko, Valery I.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 26-04-2021; Springer Nature B.V
• Subjects: Absorption spectra; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Computer Appl. in Life Sciences; Computer Applications in Chemistry; Dimers; Hydroxyl groups; Infrared radiation; Infrared spectroscopy; Molecular Medicine; Molecular structure; Original Paper; Room temperature; Theoretical and Computational Chemistry; IR spectra; DFT; Normal vibrations; Calixarenes; Hydrogen bonding
• ISSN: 1610-2940; 0948-5023
• DOI: 10.1007/s00894-021-04766-5

The IR spectra of
p
-(3-carboxy-1-adamantyl)thiacalix[4]arene (
1
-
AdCOOHTC4A
) have been studied. IR spectra of crystalline
1
-
AdCOOHTC4A
obtained at room temperature or upon heating to 250 °C or its dilute solutions lack bands of free hydroxyl groups. The frequency of hydroxyl groups at 3377 cm
−1
indicates the formation of an intramolecular H-bond along the lower rim of the
1
-
AdCOOHTC4A
molecule. On the top edge of thiacalixarene, the carboxyl groups form dimeric or cyclic tetrameric complexes via intermolecular H-bonds. The conformation of the cone persists, but there is a mutual influence of H-bonds along the upper and lower rims of the thiacalix[4]arene molecule. The structure with dimer H-bonds between carboxyl groups is 31.9 KJ/mol less preferable than the conformation with tetramer cyclic H-bonds for
1-AdCOOHTC4A
. Comparison of the absorption band of νOH alcohol hydroxyl groups in the IR spectra of
1
-
AdCOOHTC4A
at 3377 cm
−1
, with the corresponding band of
1-AdTC4A
at 3372 cm
−1
, suggests that the presence of the second system of H-bonds of carboxyl groups in the first molecule does not affect the H-bond of alcohol hydroxyl groups.
Graphical abstract