Self-assembly of a novel 2D network polymer: Syntheses, characterization, crystal structure and properties of a four-tin-nuclear 36-membered diorganotin(IV) macrocyclic carboxylate

The novel macrocyclic complex (n-Bu2SnL)4·2C6H61 (LH2 = naphthalene-1,4-dicarboxylic acid, C6H6 = benzene) has been synthesized by the reaction of di-n-butyltin oxide and rigid naphthalene-1,4-dicarboxylic acid. Single crystal X-ray diffraction analyse shows that complex 1 has a centrosymmetric tetranuclear diorganotin dicarboxylate with 36-membered macrocycle, which is formed by n-Bu2Sn and ligand alternately linking. All four Sn atoms are hexacoordinated, and the coordination environment can be considered as a skew-trapezoidal bipyramidal with an anisobidentate coordination mode of the carboxylate groups. Luminescent property study of complex 1 has shown that the fluorescent peak was blue-shifted and the fluorescent intensity strengthened markedly compared with ligand. Pilot studies indicated that complex 1 has shown good antitumor activities. This complex 1 is likely to serve as a new model for further investigation on the structure–antitumor activity relationship.

The novel macrocyclic tetranuclear diorganotin carboxylate 1 was synthesized by the self-assembly of di-n-butyltin oxide and rigid naphthalene-1,4-dicarboxylic acid. Through Sn⋯O weak intermolecular interaction, complex 1 forms two distinct one-dimensional chains and a 2D polymeric network structure with another type of tetranuclear macrocycle (II) having larger cavity. Further, intermolecular hydrogen bonds of C–H⋯O interactions stabilize the structure. In addition, studies indicate that complex 1 has fluorescence property and has shown good antitumor activities.Figure optionsDownload as PowerPoint slide