CuAAC-based assembly and characterization of a ruthenium–copper dyad containing a diimine–dioxime ligand framework

Abstract

The design of molecular dyads combining a light-harvesting unit with an electroactive centre is highly demanded in the field of artificial photosynthesis. The versatile Copper-catalyzed Azide-Alkyne Cycloaddition (CuAAC) procedure was employed to assemble a ruthenium tris-diimine unit to an unprecedented azide-substituted copper diimine-dioxime moiety. The resulting RuCu dyad 4 was characterized by electrochemistry, H NMR, EPR, UV-visible absorption, steady-state fluorescence and transient absorption spectroscopies. Photoinduced electron transfer from the ruthenium to the copper centre upon light-activation in the presence of a sacrificial electron donor was established thanks to EPR-monitored photolysis experiments, opening interesting perspectives for photocatalytic applications.

Insights into the mechanism and aging of a noble-metal free H2-evolving dye-sensitized photocathode

“…The phosphonate-derivatized Co C11P complex was prepared using the copper-catalyzed azide–alkyne cycloaddition (CuAAC) of [Cu II (DO)(DOH)N 3 pn(OH 2 )](ClO 4 ) 43 with the commercially available alkyne linker P Et C 9 C CH featuring a terminal diethyl ester phosphonate anchoring group. The resulting Cu C11PEt complex ( Fig.…”

“… 42 [Co(DO)(DOH)pn]Br 2 and [Cu(DO)(DOH)N 3 pn(OH 2 )](ClO 4 ) were prepared following reported procedures. 42 , 43 The synthesis of RBG-174 has been described elsewhere. 39 Dry dichloromethane and dry acetonitrile were obtained by distillation on CaH 2 and kept under Ar.…”

“…The crude mixture (containing the perchlorate salt of Cu C11PEt ) was purified by flash chromatography on silica gel using a gradient (39 : 1 to 8 : 2) of MeCN/aqueous KNO 3 solution (saturated solution diluted at 10%). 22 , 43 The purified fraction contains Cu C11PEt as a nitrate salt. MS (ESI+): m / z calcd for C 26 H 47 CuN 7 O 5 P 631.3; found 631.3 [M – OH 2 – NO 3 – ] + .…”

Synthesis of Ruthenium Tris‐Diimine Photosensitizers Substituted by Four Methylphosphonate Anchoring Groups for Dye‐Sensitized Photoelectrochemical Cell Applications

“…In addition to the reference 2,2′‐bipyridine (bpy) ligand, we selected 1,10‐phenanthroline (phen) and phen‐substituted derivatives, namely 5‐amino‐1,10‐phenanthroline (phenamine), dipyrido[3,2‐a:2′,3′‐c]phenazine (dppz), 1,10‐phenanthroline‐5,6‐dione (phendione) and 2‐(4‐ethynylphenyl)‐1H‐imidazo[4,5‐f][1,10]phenanthroline (EPIP) (Figure ). The latter allows further functionalization of the RuP 4 OEt ‐N ^ N complex by copper‐catalyzed azide‐alkyne cycloaddition (CuAAC) …”

“…The 4,4′‐bis(diethylphosphonomethyl)‐2,2′‐bipyridine ligand (4,4′‐(CH 2 PO 3 Et 2 ) 2 ‐bpy) was custom‐synthesized by the company Oribase Pharma, according to a previously reported procedure . The dipyrido[3,2‐a:2′,3′‐c]phenazine (dppz), 1,10‐phenantroline‐5,6‐dione (phendione), 2‐{4‐[2‐(trimethylsilyl)ethynyl]phenyl}‐1 H ‐imidazo[4,5‐f][1,10]phenanthroline (TMS‐EPIP) and 2‐(4‐ethynylphenyl)‐1 H ‐imidazo[4,5‐f][1,10]phenanthroline (EPIP) ligands were prepared according to previously reported procedures. Spectroscopic and electrochemical characterizations of complexes RuP 4 OEt ‐bpy and RuP 4 OEt ‐dppz were previously reported.…”