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A series of novel 6,6'‐diphenyl‐2,2'‐bipyridine ligands modified with the substituents at phenyl and bipyridine moieties have been prepared and used in the synthesis of pincer platinum chloride complexes 1–3, [Pt(NNC–R)Cl], where NNC–R – dimethyl 6,6'‐diphenyl‐[2,2'‐bipyridine]‐5,5'‐dicarboxylate (R = H, (1)), dimethyl 6,6'‐bis(4‐fluorophenyl)‐[2,2'‐bipyridine]‐5,5'‐dicarboxylate (R = F (2)), dimethyl 6,6'‐bis(4‐methoxyphenyl)‐[2,2'‐bipyridine]‐5,5'‐dicarboxylate (R = OMe (3)). Reactions of the obtained compounds with triphenylphosphine proceed through unusual pathway, which gives the [Pt(NNC–R)(PPh3)2Cl] products (1a–3a) containing two phosphine ligands, with the chloride retained in coordination sphere and diphenyl‐bipyridine fragment coordinated in η1‐mode through metalation of a pyridine ring. All complexes have been characterized with mass‐spectrometry and NMR spectroscopy, solid‐state structure of 1–3 and 1a, 3a was revealed by using XRD crystallography. The complexes 1–3 are phosphorescent in dichloromethane solution and in solid state. Their photophysical characteristics were determined and analyzed by DFT calculations, which gave assignment of emissive excited state character with the major contribution from the intraligand charge transfer (3ILCT, Ph→bipyridine) and ligand centered (3LC, bipyridine fragment) transitions. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue are the groups of Sergey P. Tunik and his colleagues from St Petersburg University. The image depicts the strong bathochromic shift of the emission wavelength of phosphorescent platinum(II) complexes upon their aggregation in the presence of water. Read the full text of the article at 10.1002/chem.202202207. [ABSTRACT FROM AUTHOR]

Cover Feature: Unusual Reactivity and Photophysical Properties of Platinum(II) Pincer Complexes Containing 6,6'-Diphenyl-2,2'-bipyridine Ligands (Eur. J. Inorg. B The Cover Feature b shows the reaction of platinum pincer complexes [Pt(NNC-R)Cl] (where NNC-R is dimethyl 6,6'-di(C SB 6 sb H SB 4 sb -X)-[2,2'-bipyridine]-5,5'-dicarboxylate, X = H, F, OMe) with triphenylphosphine. This reaction does not afford commonly observed substitution of chloride for the phosphine, instead insertion of two phosphine ligands into the platinum(II) environment provokes "rollover" re-coordination of the pincer ligand in the SP 1 sp mode to give an unusual structural pattern stabilized by intramolecular - stacking of the aromatic systems of the ligands. [Extracted from the article]