Hybrid charged heterometallic Pt–Ir complexes: tailoring excited states by taking the best of both worlds

Abstract

The C≡C-linkage of Pt(PR(3))(2)(C≡CAr)(2) with (C^N)(2)Ir(N^N)(+) (C^N = 2-phenylpyridine; N^N = bipyridyl) leads to hetero-bi- and trimetallic species exhibiting photophysical properties reminiscent of both [Pt]- and [Ir]-containing moieties through the generation of a [Pt] → [Ir] charge transfer excited state.

Strategic Modulation of the Photonic Properties of Conjugated Organometallic Pt–Ir Polymers Exhibiting Hybrid CT‐Excited States

“…Their syntheses and characterization are placed in the Experimental Section (see the Supporting Information). The absorption and emission spectra of 3–6 exhibit the characteristic signature expected for the [Ir] motif (Figure ) . The spectroscopic and photo­physical data of 1–6 are compared with those for 7–12 in Table .…”

“…The model complexes 1–5 and polymer 6 were synthesized in reasonable yields from dimer 13 [(dFMeppy) 2 Ir‐μ‐Cl] 2 following procedures used for the corresponding non‐fluorinated derivatives . Their syntheses and characterization are placed in the Experimental Section (see the Supporting Information).…”

“…Polymer 12 exhibits similar photophysical traits as for the model compounds 8 and 11 , making it potentially useful for photonic applications. One interesting aspect in a fundamental point of view is the nature of its excited state, which turns out to be a hybrid between the metal‐to‐ligand charge transfer ( 1,3 MLCT) for the trans ‐Pt(PBu 3 ) 2 (CCAr) 2 unit, [Pt] and the metal‐to‐ligand/ligand‐to‐ligand' charge transfer ( 1,3 ML'CT/LL'CT) for [Ir] with L = ppy . However, the linking of two or more conjugated units together almost systematically led to a red shifting of the emission band.…”

Photoisomerisation in Aminoazobenzene‐Substituted Ruthenium(II) Tris(bipyridine) Complexes: Influence of the Conjugation Pathway

“…Ligand L1 was obtained in high yield (89 %) after aqueous workup in the presence of ethylenediaminetetraacetic acid (EDTA) and purification by column chromatography. The syntheses of ligands L2 and L3 , both substituted with an ethynyl ( L2 ) or a triazolyl ( L3 ) bridge in the 5‐position (Scheme ), result from different catalysed reactions from 5‐(ethynyl)‐2,2′‐bipyridine ( 5 )14 (Scheme ). Ligand L2 was synthesised by the Pd‐catalysed Sonogashira cross‐coupling reaction15 of 5 with 4‐( N , N ‐dibutylamino)‐4′‐iodoazobenzene ( 6 ), which was previously prepared by reaction of N , N ‐dibutyl‐aniline with 4‐iodobenzene diazonium chloride.…”

“…The second step consisted of al ithium-halogen exchange by reactiono ftert-butyllithium with 2-bromopyridine at À78 8C. After transmetallation to Zn, aC HCl 3 solution of [Pd 2 (dba) 3 ], tBu 3 PH·BF 4 and 2 were added, and the reaction was heatedt or eflux until completion.L igand L1 was obtained in highy ield (89 %) after aqueous workup in the presence of ethylenediaminetetraacetic acid (EDTA) and purification by columnc hromatography.T he syntheses of ligands L2 and L3,both substituted with an ethynyl (L2)oratriazolyl (L3)b ridge in the 5-position (Scheme 3), result from different catalysedr eactions from 5-(ethynyl)-2,2'-bipyridine (5) [14] (Scheme 3). Ligand L2 was synthesised by the Pd-catalysedS onogashirac ross-coupling reaction [15] of 5 with 4-(N,N-dibutylamino)-4'-iodoazobenzene (6), which was previously prepared by reactiono fN , N -dibutyl-aniline with 4-iodobenzene diazonium chloride.…”