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Synthesis, characterization, and X-ray structure of 1,2-bis-crown-5-calix[4]arene. Modeling of metal complexation

Research paper by Zouhair Asfari, Jean-Pierre Astier, Christophe Bressot, Jacques Estienne, Gerard Pepe, Jacques Vicens

Indexed on: 01 Mar '94Published on: 01 Mar '94Published in: Journal of Inclusion Phenomena and Macrocyclic Chemistry



Abstract

1,2-bis-crown-5-calix[4]arene (3) was prepared by reacting calix[4]arene (1) with tetraethylene glycol di-p-toluenesulphonate (2) in the presence of cesium carbonate in 9% yield. The X-ray structure of (3) was determined. Crystal data for C44H52O10 are as follows: monoclinic, space groupP2/c witha=18.006(8) Å,b=10.680(4) Å,c=22.359(6) Å, β=112.93(3)°,V=3958(6) Å3,Z=4,Dcalc=1.2 g cm−3, the finalR value is 0.11 for the 1851 observed reflections (I>3σ(I)). The single crystal included two similar but slightly different molecules immobilized in a pinched-cone conformation withC2 symmetry. The two enantiomorphous molecules were analyzed by molecular mechanics using the GenMol program to model the selective alkali-metal complexation.