Facile synthesis of a ruthenium assembly and its application for light-driven oxidation of alcohols in water

Abstract

A supramolecular assembly containing two light harvesting fragments [Ru(tpy)2](2+) and one catalytic unit [Ru(tpy)(bpy)Cl](+) was synthesized in a facile manner in 90% yield, and exhibited high photocatalytic product-selectivity compared with the corresponding bimolecular system in the light-driven oxidation of alcohols using [Co(NH3)5Cl]Cl2 as a sacrificial oxidant in water at room temperature.

New trinuclear dendritic complexes with [Ru(tpy)(bpy)X]n+ (X = Cl, H2O; n = 1, 2) for enhanced water oxidation and light-driven alcohol oxidation

“…Generally, the Ru(IV) = O is proposed as the key intermediate in these reactions. Previously, our work demonstrated that the electron transfer reactions occurring in a chromophore catalyst assembly for the generation of a Ru(IV) = O oxidative intermediate can be applied to alcohol oxidation reactions [22,23]. In the present work, we also performed photocatalytic oxidation of alcohol with complex 1 as a catalyst in the presence of [Ru(bpy) 3 ]Cl 2 and [Co(NH 3 ) 5 Cl]Cl 2 (Scheme 2).…”

“…Both complexes exhibited characteristic broad and intense longwavelength absorptions, which are attributed to the metal-to-ligand charge transfer (MLCT) in nature. Compared with 1, complex 2 displayed blue-shifted MLCT absorption due to an increase in the dπ-π ⁎ energy gap caused by the Cl¯to H 2 O ligand exchange process [22,23]. Cyclic voltammetry (CV) measurements of 1 in pH 1.0 displayed one redox event at E 1/2 = 0.97 V vs normal hydrogen electrode (NHE) was observed in a 0-1.7 V potential sweep window and this redox process is assigned to Ru III/II (Fig.…”

“…In addition, many [Ru(tpy)(bpy)(H 2 O)] 2+ -based complexes have been applied as catalysts for light-driven alcohol oxidation reactions with the Ru(IV) = O species possessing excellent reactivity for the oxidation of organic substrates [20,21]. Previously, our group reported on the facile preparation of two chromophorecatalyst assemblies based on [Ru(tpy)(bpy)X] n+ catalysts for visiblelight driven photooxidation of alcohols [22,23]. In the present work, we have devoted our efforts to the preparation of conjugated dendritic complexes (Scheme 1) and investigations into their chemical water oxidation and visible-light driven alcohol oxidation activities.…”

Photocatalytic Oxygenation Reactions Using Water and Dioxygen

“…[47] When the TMP ligand was replaced by TDCPP, [(TDCPP)Mn III ] + acts as a more reactive catalyst for the oxygenation of cyclohexene and styrene than [(TMP)Mn III (H 2 O) 2 ](PF 6 ), because of the smaller steric effect of the TDCPP ligand as comparedw ith that of TMP ligand and the high redox potential. [48][49][50][51][52][53][54][55][56][57][58] Scheme2 shows the catalytic cycle of the photocatalytic oxygenation of watersoluble substrates (S) with [Co III (NH 3 ) 5 Cl] 2 + as an oxidanta nd [Ru(bpy) 3 ] 2 + as ap hotocatalyst and am anganese(III)-hydroxo porphyrin ([(Por)Mn(OH)]) as an oxygenation catalyst. [47] Av ariety of high-valent metal-oxo complexes were produced by ET oxidation of metal complexes by one-electron oxidants, such as [Ru(bpy) 3 ] 3 + and cerium(IV) ammonium nitrate (CAN), with H 2 O, catalyzing oxygenation of substrates by using H 2 Oa sa no xygen source.…”

“Click” post-functionalization of a metal–organic framework for engineering active single-site heterogeneous Ru(iii) catalysts

“…Considering the extensive use of terpyridyl ligands in coordinating with many transition metal ions (e.g., Ru, Pd, Ni, and Cu) to construct stable complexes with interesting catalytic, photovoltaic, and electrochemical properties, it is highly desirable if such terpyridyl ligands could be immobilized on MOFs and reused. [24][25][26][27] However, up to date, the incorporation of terpyridyl ligands on MOFs has never been explored. In this work, we report the successful incorporation of 2,2':6',2''-terpyridine (tpy), a tridentate oligopyridine σ-donor chelator, onto a new azides-tagged MIL-101(Cr)-N 3 through a click PSM method.…”