Supramolecular assemblages from uranyl complexes of calixarenes and potassium complexes of 18-crown-6 or dibenzo-18-crown-6

Reaction of uranyl nitrate with p-tert-butyl[3.1.3.1]homocalixarene ((LH4)-H-1) or p-tert-butylcalix[8]arene ((LH8)-H-2) has been carried out in the presence of KOH and 18-crown-6 (18C6) or dibenzo-18-crown-6 (db18C6), giving the supramolecular assemblages [K(db18C6)(H2O)(2)](3) [{UO2(L-1)}(2)K(H2O)(5)] (1) and [K(18C6)(OH)(2)][{(UO2)(2)((LH5)-H-2)(OH)}{K(18C6)}] (2). Compound 1 comprises a sandwich, complex-within-complex assemblage in which two uranyl/calixarene complexes encompass a potassium/crown ether guest. A direct bond between uranyl and K(18C6) is present in 2, in which a columnar arrangement of alternate dimetallic calixarene complexes and potassium/crown ether species is formed. (c) 2007 Elsevier B.V. All rights reserved.