Binuclear Coordination Assemblies of Metal Tetraphenylporphyrins (M = Mn, Fe, and In) with Anionic Thioindigo Bridges as Promising Magnetic Systems with Tunable Properties.

A series of hybrids comprising two metal (Mn, Fe, and In) tetraphenylporphyrins axially substituted with anionic bidentate -thioindigo ligands (TI) were obtained. Substitution of the axial chloride anion by an oxygen atom of the dye forms short M-O bonds. Crystalline binuclear assemblies (TI)·{[MnTPP]·[MnTPP]}·CHCl ( = 2 for or 1 for ) and (TI){[MTPP]}·CHCl (M = Fe and = 2 for , M = In and = 1 for ) were synthesized. The thioindigo (TI) dianion and metal (Fe and In) atoms in TPPs maintain their initial charge states during the formation of and , allowing the separation of paramagnetic Fe or diamagnetic In ions by a diamagnetic TI bridge. Strong antiferromagnetic coupling is observed between Fe ( = 5/2) centers in complex . Partial reduction of Mn to Mn occurs upon the formation of and , leading to assemblies containing three paramagnetic centers: Mn ( = 5/2), Mn ( = 2), and TI radical anion ( = 1/2). Orthogonal arrangement of TPP and TI molecules in provides strong ferromagnetic coupling. Weak antiferromagnetic coupling is realized in due to the rotation of the TI bridge.