Synthesis and X-Ray Structure of 25-Acetoxy-26,27,28-trimethoxycalix[4]arene

摘要

25-Acetoxy-26,27,28-trimethoxycalix[4]arene was synthesized by the treatment of calix[4]arene trimethyl ether with acetyl chloride in the presence of NaH. The solution conformation was inferred as a partial cone conformation based on the 1H-and 13C NMR spectra. The crystal structure has been determined by X-ray diffraction method. The crystals are monoclinic, space group P21, a=8.186 (1), b=17.137 (2), c=19.878 (3) ∈, モ =95.67 (1)∑, Z=4, V=2774.90 ∈3, Dc= 1.22 g cm-3, Dm=1.23 g cm-3. The intensity data were collected on an Enraf-Noninus CAD-4 Diffractometer with a graphite monochromated Cu-Kメ radiation. The structure was solved by direct method and refined by full-matrix least-squares methods to a final R value of 0.054 for 3675 observed reflections. The molecule possesses a partial cone conformation with one flattened phenyl unit, in which one anisol ring, distal to the ester ring, is inverted. The acetoxyphenyl ring is flattened.