Electrochemical Synthesis and Characterization of Tin(IV) Complexes of Dianionic Terdentate Schiff Base Ligands

Abstract

Abstract Tin(IV) complexes of the series of dianionic terdentate Schiff bases N‐[(2‐pyrroyl)methylidene]‐N′‐tosylbenzene‐1,2‐diamine , (H 2 L 1 ), N‐[(2‐hydroxyphenyl)methylidene]‐N′‐tosylbenzene‐1,2‐diamine (H 2 L 2 ) and some R substituted 2‐{[(2‐hydroxyphenyl)imino]methyl}phenols [R = H (H 2 L 3 ), 4,6‐(OCH 3 ) 2 (H 2 L 4 ), 3‐(OC 2 H 5 ) (H 2 L 5 ) and 3,5‐Br 2 (H 2 L 6 )] have been synthesized. The compounds were obtained by the electrochemical oxidation of a tin anode in a cell containing an acetonitrile solution of the corresponding ligand. The complex [SnL 1 2 ] was also obtained by reaction of SnCl 2 ·2H 2 O and H 2 L 1 in methanol in the presence of triethylamine. The crystal structure of the ligand [H 2 L 6 ] and the complexes [SnL 1 2 ] (1) , [SnL 2 2 ] (2) , [SnL 3 2 ] (3) and [SnL 6 2 ] (6) were determined by X‐ray diffraction. In the complexes, the tin atom is in an octahedral environment coordinated by two dianionic terdentate ligands. Spectroscopic data for the complexes (IR, 1 H and 119 Sn NMR and mass spectra) are discussed and related to structural information.