Exploring the 2,2'-diamino-5,5'-bipyrimidine hydrogen-bonding motif : A modular approach to alkoxy-functionalized hydrogen-bonded networks

The programmed self-association of 2,2'-diamino-4,4'-dialkoxy-5,5'- bipyrimidines allows for the de novo construction of alkoxy-functionalized H- bonded ribbons and sheets as evidenced by X-ray crystallographic analysis. The data provide insight into the interplay of the different structural and interactional features of the molecular components to the generation of the supramolecular assembly. Hydrophobicity of the didodecyl side chains of 4c leads to the dominance of the H-bonding factor, resulting in the formation of a fully interconnected array. These results define the utility of the of 2,2'-diamino-4,4'-dialkoxy-5,5'-bipyrimidines as a potential scaffold for the attachment of electro- or photochemically active alkoxy residues for self- assembled functional supramolecular materials. © 1998 Neue Schweizerische Chemische Gesellschaft, Switzerland