Trapping of ZnCl2 by bipyridyl-functionalized organotin sulfide clusters, and its effect on optical properties

Abstract

We report the syntheses of two new organotin sulfide clusters with heteroaromatic substituents. A phenanthroline-functionalized tin sulfide cluster [(R^PhenSn)₄S₆] (1; R^Phen = CMe₂CH₂C(Me)N–NC(H)C₁₂H₇N₂) and a bipyridyl-terminated cluster [(R^4-bipySn)₄S₆] (2; R^4-bipy = CMe₂CH₂C(Me)N–NC(H)-4-C₁₀H₇N₂) were obtained from reactions of the hydrazone-functionalized organotin sulfide cluster [(R^NSn)₄S₆] (R^N = CMe₂CH₂C(Me)N-NH₂) with 1,10-phenanthroline-5-carboxaldehyde or 2,2′-bipyridine-4-carbaldehyde. 1 and 2 were tested towards their capability of trapping metal ions by means of the terminal chelating ligands. The reaction of 2 with ZnCl₂ afforded the cluster compound [(R^4-bipyZnCl₂Sn)₄S₆] (5), in which four ZnCl₂ units are coordinated by the heteroaromatic organic groups. We discuss the structures and demonstrate the effect of ZnCl₂ trapping on optical absorption and luminescence properties.