Anion Dependent Water Clusters Encapsulated Inside a Cryptand Cavity.

A series of water clusters encapsulated inside a cryptand cavity were obtained in the cryptand-acid supramolecular adducts of [(H 2O) 2⊂(H 6L)][H 2PO 4] 6(H 2O) 3( 1·3H 2O), [(H 2O) 3⊂(H 6L)][H 2PO 4] 6(H 2O) 11( 2·11H 2O), [(H 2O) 3⊂(H 6L)][CH 3(C 6H 4- p)SO 3] 6(H 2O) 4( 3·4H 2O), and [(H 2O) 6⊂(H 6L)][SO 4] 3(H 2O) 13( 4·13H 2O) (L = N[(CH 2) 2NHCH 2(C 6H 4- p)CH 2NH(CH 2) 2] 3N). In 1and 2, H 6L 6+is hydrogen bonded to six H 2PO 4−through its protonated nitrogen atoms to form two (O···H−N−H···) 3rings at two poles of H 6L 6+. A well encapsulated water dimer, and a circle- and cage-shaped trimer of [H 2PO 4] 3are formed in 1. A well encapsulated circular water trimer and a bowl-shaped trimer of [H 2PO 4] 3are formed in 2. In 3, the steric effect of the tolyl group of [CH 3(C 6H 4- p)SO 3] −causes a change in the conformation of H 6L 6+to generate a favorable environment for a linear water trimer inside the crystand cavity. In 4, H 6L 6+bonds three SO 42−anions through the protonated nitrogen atoms at the one pole, and a quasi-prismatic hexamer water cluster is formed inside the cryptand cavity. [ABSTRACT FROM AUTHOR]