Synthesis, Crystal Structures, and Properties of (4,4'‐Hbipy)2[Sn2(C2O4)3] and (4,4'‐Hmbipy)[SnX2] (X = C2O42–, m = 2; X = Cl, m = 0; bipy = bipyridine)

Abstract

Three new tin coordination compounds (4,4'‐Hbipy)2[Sn2(C2O4)3] (1), (4,4'‐H2bipy)[Sn(C2O4)2] (2), and SnCl2(4,4'‐bipy) (3) were synthesized under hydro‐(solvo‐)thermal conditions and their crystal structures were determined by single‐crystal X‐ray diffraction. Compound 1 exhibits a ionic structure based on discrete [4,4'‐Hbipy]+ cations and [Sn2(C2O4)3]2– anions. These two units are linked via N–H···O hydrogen bonds to form a pseudo‐one‐dimensional zigzag hydrogen‐bonded chain. In compound 2, four‐coordinate Sn atoms form monomeric tin dioxalato complexes, which are connected to the doubly protonated [4,4'‐H2bipy]2+ cations through N–H···O hydrogen bonded to give a one‐dimensional zigzag hydrogen‐bonded chain. Compound 3 forms a three‐dimensional hydrogen‐bonded network, in which 1∞[SnCl2(4,4'‐bipy)] linear chains are interconnected to each other by C–H···Cl hydrogen bonding. The solid‐state UV/Vis/NIR diffuse reflectance spectroscopy shows that three compounds are broadband semiconductors. The thermogravimetric analysis evidences the thermal stability of the three compounds up to 175, 201, and 246 °C, respectively.