Enhancement of Chiroptical Responses of trans‐Bis[(β‐iminomethyl)naphthoxy]platinum(II) Complexes with Distorted Square Planar Coordination Geometry

Abstract

Invited for this month's cover picture are the groups of Masahiro Ikeshita and Takashi Tsuno at Nihon University and Yoshitane Imai at Kindai University (Japan). The cover picture shows the comparison of circularly polarized luminescence (CPL) properties of square planar platinum(II) complexes with different coordination geometry. Computational studies have been carried out to investigate these structure‐dependencies, and revealed that the distortion of the coordination geometry results into an enhancement the chiroptical responses of these compounds. Read the full text of their Research Article at 10.1002/open.202100277.

Multi-colour circularly polarized luminescence properties of chiral Schiff-base boron difluoride complexes

“…As part of our program aimed at the creation of novel functional materials, we have been investigating luminescent organic and organometallic complexes bearing Schiff-base ligands. 21 Previously, we have reported that phosphorescent Pt( ii ) complexes with chiral Schiff-base ligands exhibit tunable CPL properties in the poly(methyl methacrylate) (PMMA) film-dispersed state. 21 b In the present work, we focused on boron difluoride complexes 22 with chiral ( N , O )-bidentate Schiff-base ligands as CPL emitters (Fig.…”

Liquid Based Circularly Polarized Phosphorescence of a Chiral Schiff Base Platinum(II) Complex Bearing Polyethylene Glycol Chains

“…Our group has been investigating chiroptical properties of organic and organometallic compounds with chiral Schiff‐base ligands as novel functional materials [11h,i,15] . Most recently, we found that chiral Schiff‐base platinum(II) complexes exhibit tuneable CPP properties in solution and the polymer film‐dispersed state [11h,i] . Based on these background, we aimed to create CPP‐active liquids based on chiral Schiff‐base platinum(II) complexes.…”

Circularly polarized phosphorescence with a large dissymmetry factor from a helical platinum(ii) complex

“…[1][2][3] Square planar platinum(II) complexes are widely known for their highly efficient phosphorescent emission, and CPP materials have been created by introducing chiral ligands. [4][5][6][7][8][9][10][11][12][13][14][15][16][17] Several chiral platinum(II) complexes have been reported to show CPP with large dissymmetry factors (g lum = 2DI/I = 2(I L À I R )/(I L + I R )) 18 in the aggregated state. 7,8,12,16 In particular, the co-assembly of achiral and chiral platinum complexes reported by You and coworkers showed a considerably large g lum value of 0.064 from a magnetically-allowed metal-metal-to-ligand charge transfer (MMLCT) transition.…”

“…The most successful example was reported by Autschbach, Crassous and coworkers in which a platinum(II) complex with a [6]helicene framework exhibited CPP of the order of 10 À2 in the solutiondispersed state at room temperature. 4,27 Our research group has been investigating the photophysical properties of chiral transition metal complexes and recently found that Schiff-base platinum(II) complexes with a distorted square planar coordination platform exhibit tunable CPP properties in solution, 11,13,14 in the polymer-dispersed state, 10 and in the solvent-free liquid state. 12 In the present study, we designed a novel chiral platinum complex 1 with a Schiff-base [4]helicene ligand and the photophysical properties of the complex were compared with its analogue 2 (Scheme 1).…”