Catalytic Reactions by Heterobimetallic Carbonyl Complexes with Polar Metal–Metal Interactions

Abstract

Heterobinuclear catalysts capable of bimetallic cooperative bond activation provide an alternative pathway to approach the discovery of novel and unique reactivity and selectivity in catalytic transformations, complementing more traditional mononuclear precious metal catalysts. This review summarizes recent advances in homogenous catalysis using heterobimetallic carbonyl catalysts with polar metal–metal interactions.1 Introduction2 Hydrogenation and Hydrofunctionalization3 Carbonylation and Carboxylation4 Oxidative Transformations5 Conclusion and Outlook

Aluminum-Containing Heterobimetallic Complexes as Versatile Platforms for Homogeneous Catalysis

“…Ye and co-workers also reported the double activation of formyl C−H and β′-C(sp 3 )−H bonds of N-formamyl enamides for synthesizing 2-pyridones in 58−99% yield using a bimetallic PO-L 5 −Ni−Al catalyst (Figure 32). 107 Although in the previously reported methods the C−H functionalization occurs at vinylic C(sp 2 )−H position due to its higher reactivity, here the less reactive β′-C(sp 3 )−H position was selectively activated.…”

“…Heterobimetallic synergy has emerged as a powerful strategy in homogeneous catalysis. − Whereas the behaviors of a mononuclear metal catalysts are most readily controlled by the stereoelectronic properties of their ligands, heterobimetallic catalysts gain cooperative reactivity and additional tunability from the nature of the metal pairing . Nature utilizes heterobimetallic active sites in metalloenzymes to efficiently catalyze various transformations, many of which remain challenging for synthetic chemists .…”

Peraurated ruthenium hydride carbonyl clusters: aurophilicity, isolobal analogy, structural isomerism, and fluxionality

“…In addition, (polarized) heterometallic M–Au bonds may contribute to enhanced catalytic properties. 33–38…”

Reactivity of Heterobimetallic Ion Pairs in Formic Acid Dehydrogenation

“…Bifunctional catalysts bearing the basic and acidic sites on the same molecule or on different ones demonstrate good efficiencies in a great variety of catalytic processes. , Braunstein and Mankad have developed cooperative bimetallic systems featuring polar metal–metal bonds or frustrated transition-metal Lewis acid/base pairs that catalyze versatile transformations from C–C and C–B coupling reactions to hydrogenation. , Related bimetallic complexes (η 5 -C 5 R 5 )­Ru­(CO)­(μ-dppm)­M­(CO) 2 (η 5 -C 5 H 5 ) (R = H, CH 3 ; M = Mo, W) with the metal–metal bond reported by Lau’s group showed catalytic activities in the formic acid dehydrogenation. , However, they are not very efficient, even under harsh conditions (10 mol % catalyst, THF, 80 °C), due to the formation of a stable cationic complex featuring a bridging hydride (Ru–(μ-H)–Mo). An unusual concept of bifunctional formic acid dehydrogenation catalyst has been described recently by Esteruelas’ group.…”