Hydrogen Photoevolution from a Green‐Absorbing Iridium(III)–Cobalt­(III) Dyad

Towards Noble‐Metal‐Free Dyads: Ground and Excited State Tuning by a Cobalt Dimethylglyoxime Motif Connected to an Iron N‐Heterocyclic Carbene Photosensitizer

“…Figure S1–7). This can be attributed to a small electron withdrawing effect of the cobalt fragment, which has also been found for related bimetallic iridium‐cobalt systems , . In contrast, 2 shows a significantly stronger bathochromic shift by 33 nm compared to non‐methylated 1 , since π‐accepting capabilities of the polypyridyl ligand increase.…”

“…Based on our previously published heteroleptic complex bearing a tridentate bis‐NHC ligand and a terpy (terpy = 2,2′:6′,2′′‐terpyridine) ligand, the related complex [FeL1(pyterpy)][PF 6 ] 2 1 was synthesized (pyterpy = L2 = 4′‐(4′′′‐pyridyl)‐2,2′:6′,2′′‐terpyridine; L1 = 2,6‐bis[3‐(2,6‐diisopropylphenyl)imidazol‐2‐ylidene]pyridine) in order to utilize the fact that the electronic nature of the substituents attached to the 4′ position of terpy allows significant control over the photophysical properties . By employing 4‐pyridyl, pendant‐functionalization by protonation, methylation, or coordination of metal fragments allow multiple applications. Based on 1 , the synthesis and structure of a new bimetallic complex 3 shown in Scheme , which connects an iron(II) center and a chlorobis(dimethylglyoximato)cobalt(III) motif, is presented (dimethylglyoximato = dmgH).…”

A Heterobimetallic AuIII‐PtII Photocatalyst for Water Reduction to Hydrogen

“…These values are comparable to those for other bimetallic polypyridyl complexes like [{(bpy) 2 Ru(dpp)} 2 RhCl 2 ] 5+ with dimethylaniline (≈60 TON) and [(bpy) 2 Ru(bpy‐4‐CH 3 ,4′‐CONHCH 2 (4‐py)Co(dmgBF 2 ) 2 (OH 2 )](PF 6 ) 2 with TEA (≈96 TON), and are better than those of the Ru‐Pt system such as [RuPt]Cl 2 ⋅3 H 2 O with ethylenediaminetetraacetic acid (EDTA) (TON ≈5 after 10 hours) and [(bpy) 2 Ru(II)(phen‐NHCO‐bpy‐CN)Pt II Cl 2 ] 2+ with EDTA ((TON=25 after 12 hours) . However, complex 1 exhibited rather low TON compared to many other supramolecule catalysts, probably due to its shorter emission lifetime. According to the relative reports, the excited state lifetimes of reported bimetallic complexes are usually multiples even ten times of that of 1 , enabling the proceeding of the slow photochemical processes .…”

A Bisamide Ruthenium Polypyridyl Complex as a Robust and Efficient Photosensitizer for Hydrogen Production

“…Cobaltoximes are among the most studied molecular catalysts for H 2 production in electrocatalysis and photocatalysis –. For an efficient photocatalytic system, the PS and the catalyst must be in close proximity for efficient electron transfer; many assemblies exist that are covalently linked or connected by pendant pyridine (py) on the PS, which coordinates the catalysts ,,. Indeed, the better the electron transfer, the lesser is the probability of PS decomposition induced by ligand dissociation; for example, the multi‐metallic center‐based supramolecular assembly Ru–Co 6 has better efficiency than the dissociated [Ru(bpy) 3 ] 2+ –[Co(dmgH) 2 ] + (dmgH=dimethylglyoxime) system .…”