Novel supramolecular organizations in melamine complexes with 4,4 '-bipyridyl and silver nitrate

Complexes of melamine with 4,4'-bipyridyl and AgNO3 having compositions, C1 0H8N2:0.5(C3H6N6):H2O and [Ag(C3H6N6)]NO3, respectively, have been prepared for the first time. A crystallographic investigation has shown unique hydr ogen bonding patterns in the two systems. The melamine-4,4'-bipyridyl compl ex shows a supramolecular organization wherein hydrogen bonding between mel amine and water molecules results in tapes. The tapes are connected by hydr ogen bonding to 4,4'-bipyridyl giving rise to a rectangular box. In the mel amine-AgNO3 complex, the melamine molecules are bound to Ag+ ions forming N -Ag-N chains, giving rise to a helix. The helices are held together by inte rchain hydrogen bonds. (C) 2001 Elsevier Science B.V. All rights reserved.