Self-assembly of ionic triorganotin(IV) complexes of tetrafluorophthalic acid with a tetranuclear macrocyclic or polymeric structure: syntheses,characterization and crystal structures

Four triorganotin(IV) complexes constructed from tetrafluorophthalic acid (H₂tfp) with a 1?:?1?:?1 molar ratio of H₂tfp: Et₃N: R₃SnCl gave two of type {R₃Sn (tfp)].Et₃NH}₄ (R?=?Me 1, R?=?n-Bu 2), and two of type R₃Sn (tfp).Et₃NH] _n (R?=?PhCH₂ 3, Ph 4). All the complexes are characterized by elemental, IR, ¹H, ¹³C and ¹¹⁹Sn NMR analyses. Complexes 1 and 4 were also confirmed by X-ray crystallography. Complex 1 is tetranuclear with a 28-membered C₁₆O₈Sn₄ macrocyclic ring system with a cavity. The supramolecular structure of 1 has been found to consist of a three-dimensional network built up by intermolecular N–H?···?O, C–H?···?O hydrogen bonds and C–F?···?F weak interactions. Complex 4 is an infinite polymeric structure. The salient feature of the supramolecular structure of 4 is that of a two-dimensional plane, in which intermolecular N–H?···?O and C–H?···?π hydrogen bonds are important.