Synthesis, characterization, and hydrolytic behavior of diorganotin(IV) coordination polymers with layered structural motifs

The synthesis and structural characterization of the layered diorganotin coordination polymers nBu₂Sn(HL)(OSO₂Me) (1) and nBu₂Sn(HL¹)(OSO₂Me) (2) derived from the silaalkylphosphonic acids RR¹₂Si(CH₂)₃P(O)(OH)₂ [R = Ph, R¹ = Me (H₂L); R = R¹ = Et (H₂L¹)] are presented. The structure of H₂L exhibits O-H···O hydrogen bonding and π-π interactions to form a unique three-dimensional supramolecular assembly in the solid state. The asymmetric units of 1 and 2 are composed of centrosymmetric eight-membered [-Sn-O-P-O-]₂ cyclic rings with appended sulfonate groups, which provide layered connectivity to the structures. For 1, the presence of C-H···π interactions between the dangling phenyl rings of the silaalkyl chains favors a lamellar arrangement with an interlayer spacing of 16.9 Å. Upon exposure to humid conditions, these polymers undergo slow transformation to nBu₂Sn[O₃P(CH₂)₃SiRR¹₂] with the elimination of methanesulfonic acid.