Synthesis and structural chemistry of bis(pyridylimino)isoindolato–ruthenium complexes and their activity as mediators in the atom transfer radical polymerization (ATRP) of styrene

The reaction of the Bispyridyl Isoindole (BPI) type ligands L1 and L2 (L1 = 1,3-Bis(2-(4-tert-butylpyridyl)imino) isoindole, L2 = 1,3-Bis(2-(5-bromo)imino)-5,6-dimethylisoindole) with [Ru(μ-Cl)2(cod)]x in presence of triethylamine using coordinating solvents like acetonitrile, dimethyl sulfoxide or pyridine cleanly gave the complexes [{BPI(L1,L2)}RuII(Cl)(S)2] (L1: S = acetonitrile (1), dimethyl sulfoxide (2), pyridine (3); L2: S = acetonitrile (4), dimethyl sulfoxide (5), pyridine (6)). In these complexes the BPI ligands meridionally coordinated to the ruthenium center as established by X-ray diffraction for complexes 3 and 6. The catalytic activity in the direct ATRP (Atom Transfer Radical Polymerization) of styrene was tested for complexes 1–6.

Graphical abstractBis(pyridylimino)isoindolato(BPI)–ruthenium complexes were prepared and tested for the catalytic activity in the direct ATRP (Atom Transfer Radical Polymerization) of styrene.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Bis(pyridyliminoisoindolates(BPI) as ancillary ligands in ruthenium complexes. ► Catalysts in the direct atom transfer radical polymerization of styrene. ► Negligible effects of the ligand substitution pattern.