Abstract The crystal structure of the molecular adduct of 5-mono [(4-nitrophenyl) azo]-25, 26, 27, 28-tetrahydroxycalix [4] arene (2) with chloroform (C 34 H 27 N 3 O 6⋅ CHCl 3) was determined by X-ray crystallographic analysis. It was found to possess a monoclinic space group P 2 (1)/n, with a= 15.9306 (13) Å, b= 10.6293 (9) Å, c= 20.3194 (17) Å, β= 110.480 (2)° and D calc= 1.428 Mg/m 3 for Z= 4. Crystal data indicated that the calix [4] arene ...
