Synthesis and characterization of diethyltin-based three dimensional self-assemblies derived from sulfonate-phosphonate ligands

Diethyltin(methoxy) methanesulfonate reacts readily with equimolar amount of t-butylphosphonic acid (RT, 8-10 h) in moist dichloromethane and methanol to afford [(Et2Sn)(6)(O3PBut)(4)(OSO2Me)(4)center dot CH2Cl2](n) (1) and [(Et2Sn)(6)(O3PBut)(4)center dot(OSO2Me)(4)center dot 2H(2)O](n) (2), respectively. The identity of these compounds has been established by IR, multinuclear (H-1, C-13, P-31 and Sn-119) NMR as well as X-ray crystallographic studies. Despite apparent similarity in the composition, a marked difference in the structural motifs between 1 and 2 is evident in the solid state. For 1, the formation of three-dimensional self-assembly results from mu(3)-phosphonate and mu(2), mu(3)-sulfonate binding modes and exhibits continuous channel of voids which are occupied by disordered CH2Cl2 molecules. In contrast, the sulfonate ligands in 2 act exclusively in mu(2)-fashion and hydrogen bonding interactions (O-H center dot center dot center dot O) between coordinated water molecules and methanesulfonate groups is significant in the construction of 3D supramolecular assembly.