263162-67-0Relevant articles and documents
Synthesis, structure, and complexing property of p-tert-butylcalix[4]arene 1,3-digallate
Nomura, Eisaku,Hosoda, Asao,Taniguchi, Hisaji
, p. 779 - 781 (2000)
(figure presented) p-tert-Butylcalix[4]arene 1,3-digallate, which contains a nonbonded close contact between galloyl groups, was synthesized and its structure was determined by dynamic 1H NMR and X-ray crystallography. The electronic spectra showed that a new absorption band of the complexes appeared at a longer wavelength region upon adding Ag+ ion. This spectral shift was explained in terms of the interaction between the facing galloyl groups of the lower rim of the calixarene framework.
Synthesis and conformational property of tannin-like p-tert-butylcalix[4]arene 1,3-diesters stabilized by intramolecular hydrogen bonds
Nomura, Eisaku,Hosoda, Asao,Taniguchi, Hisaji
, p. 8030 - 8036 (2007/10/03)
Tannin-like p-tert-butylcalix[4]arene 1,3-digallate was synthesized, and its conformational property was investigated by dynamic 1H NMR and X-ray crystallography. It was found that the 3-OH (or 5-OH) group of the galloyl group in p-tert-butylcalix[4]arene 1,3-digallate is placed at the position where an unusual nonbonded close contact is observed between the OH group and the aromatic ring of the galloyl group facing each other. The calixarene 1,3-diesters of various hydroxybenzoic acids were also prepared, and the conformational properties of those calixarenes were compared with that of p-tert-butylcalix[4]arene 1,3-digallate. A significant contribution of the 3- and 5-OH groups in pendant groups toward the close contact was found. It was suggested that the conformation of p-tert-butylcalix[4]arene 1,3-digallate was stabilized by intramolecular hydrogen bonds including OH···O and OH-π interactions.
