Oxido-alcoholato/thiolato-molybdenum(VI) complexes with a dithiolene ligand generated by oxygen atom transfer to the molybdenum(IV) complexes

Inspired by Nature—Functional Analogues of Molybdenum and Tungsten-Dependent Oxidoreductases

“…The molybdenum center can, for instance, be substituted by rhenium, due to the diagonal relationship between these two metals leading to an additional class of efficient OAT reagents [25][26][27][28][29]. Commonly, the examination of OAT reactivity includes natural and non-natural oxygen acceptors (organic phosphines, sulfite, selenite, arsenite) and oxygen donors (N-oxides, S-oxides), which still represent well-established, state-of-the-art approaches towards modelling either individual half reactions or entire OAT-only catalytic cycles when they are combined [21][22][23]27,[30][31][32][33][34]. This means that a reduced substrate and an oxidized substrate are mixed with the functional model complex, which is taking the oxygen atom from one substrate and delivering it to the other without passing through any PCET.…”

“…Sugimoto and others, remarkably, further extended their respective investigations beyond OAT, also looking at oxygen's heavier congeners sulfur and selenium. The transfers of oxygen, sulfur, and selenium atoms to organophosphines were compared considering tungsten as well as molybdenum complexes as oxidants [33,[45][46][47][48][49][50]. The investigations focused on mechanistic and kinetic details of these reactions.…”

“…In their experiments, Ueyama et al found an accelerated addition of the oxygen of TMAO to the [Mo IV O(2N-bdt)2] 2− complex in contrast to the non-substituted related benzene-1,2-dithiolate-derived complexes introduced by Garner In the other type of half cycle reaction, a substrate donates its oxo function as an oxygen atom to the metal ion center accompanied by the oxidation of M IV to M VI . Respective OAT donor reagents/substrates are often derived from trimethylamine-N-oxide (TMAO) since this is actually also a natural substrate for TMAO reductase, or dimethylsulfoxide (DMSO), as in the DMSO reductase enzyme [30,33,51,52]. In 2006, Ueyama and others designed a novel aromatic dithiolene ligand 1,2-S 2 -3-R-CONHC 6 H 3 (2N-bdt; R=CH 3 , t Bu, CF 3 , CPh 3 , C(C 6 H 4 -4-t Bu) 3 ) (Figure 6b), bearing two amide moieties adjacent to the dithiolene in order to enable intramolecular hydrogen bonding in their complexes since H bonds play important roles for the enzymes' active sites and reactivities [53].…”

Interligand communication in a metal mediated LL′CT system – a case study

“…3 Such systems have been modeled with biomimetic compounds to better understand their mechanism of action. 4,5 Similar approaches have been utilized to model non-innocent dithiolene systems, [6][7][8] however, only dithiolene ligands of like oxidation states have been utilized. A model system with dithiolene ligands in different redox states can be useful in understanding interligand communication and activity of molybdenum and tungsten containing enzymes.…”

Carbon-supported ruthenium catalysts prepared by a coordination strategy for acetylene hydrochlorination

“…Until now, several strategies such as ligand coordination or strong metal-support interaction have been reported to regulate the electronic structure of metal ions. [30][31][32] Tian et al investigated the coordination behavior between the theophylline (THP) molecule and Au(III) ion. The stability constant, Kf, of the THP-Au(III) ion is 2.7 × 10 35 [33].…”