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·CH2Cl2]n (1) and [(Et2Sn)6(O3PBut)4(OSO2Me)4·2H2O]n (2), respectively. The identity of these compounds has been established by IR, multinuclear (1H, 13C, 31P and 119Sn) 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 μ3-phosphonate and μ2, μ3-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 μ2-fashion and hydrogen bonding interactions (O–H⋯O) between coordinated water molecules and methanesulfonate groups is significant in the construction of 3D supramolecular assembly.