Complexation ofp-xylene withp-isopropylcalix[4]arene: Crystal structures and thermal analysis of the empty form and the (1 : 1) and (2 : 1) complexes

This paper concerns inclusion complexes of thep-isopropylcalix[4]arene host withp-xylene as guest. It is shown that from a saturated solution inp-xylene, the macrocycle gives a 1 : 1 complex; on heating, the 1 : 1 complex is transformed into a 2: 1 complex, and then into the empty macrocycle. The compounds are studied by differential scanning calorimetry, thermogravimetry and X-ray powder diffraction; the three crystal structures are reported showing the arrangements of the macrocycles with and without their guests.Supplementary data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82143 (59 pages).