Tin Alkylarsonate Clusters: C−H···X (X = Cl, O, and π) Interaction-Mediated Supramolecular Formation

Reactions of Ph3SnCl or Ph3SnOH with the alkylarsonic acids, RAsO3H2, where R = n-propyl, n-butyl, benzyl, and 4-NO2-benzyl, have led to two types of tin oxo clusters: [Sn3Cl3(μ3-O)(R′O)3]2(RAsO3)4 [R = n-Bu, R′ = Et (1); R = n-Pr, R′ = Et (2); R = Bz, R′ = Et (3); R = n-Pr, R′ = Me (4), and R = 4-NO2−Bz, R′ = Et (5)] and [(PhSn)3(RAsO3)3(μ3-O)(OH)(R′O)2]2Sn [R = n-Pr, R′ = Et (6) and R = 4-NO2-Bz, R′ = Et (7)]. Two types of structural units, [Sn3(μ3-O)(μ2-OR′)3] for compounds 1−5 and [Sn3(μ3-O)(μ2-OR′)2] for compounds 6 and 7, were obtained by subtle changes of the organotin precursors. For the first time, hydrogen-bonding interactions such as C−H···Cl, C−H···O, and C−H···π were investigated in the crystal structures of tin alkylarsonate clusters (2−7). The cumulative effects of these weak interactions result in one-, two-, and three-dimensional suparmolecular architectures of 2−7.