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)

Three new tin coordination compounds (4,4'-Hbipy) 2 [Sn 2 (C 2 O 4 ) 3 ] ( 1 ), (4,4'-H 2 bipy)[Sn(C 2 O 4 ) 2 ] ( 2 ), and SnCl 2 (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 [Sn 2 (C 2 O 4 ) 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'-H 2 bipy] 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 ∞ [SnCl 2 (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.