Supramolecular Chemistry and Anion Binding in Palladium(II) and Silver(I) Complexes Containing N , N ′‐Dipyridylxanthene‐4,5‐dicarboxamide Ligands

Two new ligands, 2,7‐di‐ tert ‐butyl‐9,9‐dimethyl‐ N , N ′‐di(3‐pyridyl)‐ ( 1 ) and ‐ N , N ′‐bis[(3‐pyridyl)methyl]xanthene‐4,5‐dicarboxamide ( 2 ), and their complexes with palladium(II) and silver(I) are reported. Intramolecular hydrogen bonding orients the ligands so as to favour formation of macrocyclic complexes, and the structures of [Pd 2 X 4 (μ‐ 1 ) 2 ] ( 3a ), X = Cl; ( 3b ) X = Br, and [Ag 2 (μ‐ 2 ) 2 ](CF 3 SO 3 ) 2 ( 5a ) are reported. Intermolecular hydrogen bonding can also occur and can lead to supramolecular self‐assembly to give sheet 3a or ribbon 5a structures, or serve to bind anions or solvent molecules. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)