Reactivity of [Ru₃(CO)₁₂] with a Phosphine-Functionalized Imidazol-2-ylidene and Its Imidazolium Salt

Abstract

The trinuclear cluster [Ru 3 (CO) 12 ] reacts at room temperature with the phosphine-functionalized N-heterocyclic carbene (NHC) ligand 1-[2-(diphenylphophino)ethyl]-3-methylimidazol-2-ylidene (dppeImMe), in 1:1 mol ratio, to give the edge-bridged trinuclear derivative [Ru 3 (μ-κ 2 C,P-dppeImMe)(CO) 10 ] (1). The use of a 1:3 [Ru 3 (CO) 12 ] to dppeImMe mol ratio leads to the mononuclear derivative [Ru(κ 2 C,P-dppeImMe)(CO) 3 ] (2), which has a trigonal-bipyramidal ligand arrangement with the NHC and phosphine fragments of the dppeImMe ligand in axial and equatorial positions, respectively. Upon gentle heating (refluxing THF), compound 1 is transformed into the face-capped dihydrido derivative [Ru 3 (μ-H) 2 (μ 3 -κ 3 C 2 ,P-dppeImCH)(CO) 8 ] (3), which arises from the oxidative addition of two C-H bonds of the N-methyl group of the dppeImMe ligand. The trinuclear salt [Ru 3 (κP-dppeHImMe) on each Ru atom, has been prepared by treating [Ru 3 (CO) 12 ] with the salt [dppeHImMe][BF 4 ]. The deprotonation of 4[BF 4 ] 3 with three equivalents of K[N(SiMe 3 ) 2 ] is an alternative way to prepare the mononuclear complex 2.

A Carbene‐Rich but Carbonyl‐Poor [Ir6(IMe)8(CO)2H14]2+ Polyhydride Cluster as a Deactivation Product from Catalytic Glycerol Dehydrogenation

“…Previously reported Ru and Os clusters typically have only 1–2 NHC ligands per cluster;12–14 attempts to incorporate more than two such ligands failed 14a. 15, 16 Cluster formation from mononuclear metal–NHC precursors is unknown, but this cluster contains a record number of NHC ligands. The unhindered NHC ligand, with only NMe groups, probably facilitates the binding of multiple ligands.…”

The N-heterocyclic carbene chemistry of transition-metal carbonyl clusters

“…57), which has a trigonal bipyramidal ligand arrangement with the dppeImMe NHC and phosphane fragments in axial and equatorial positions, respectively (Scheme 21). 55 Upon gentle heating (refluxing THF), compound 56 is transformed into the face-capped dihydrido derivative 60), which contains a bridging ligand that arises from the metalation of the pyridine ring in the 6-position (Scheme 23). 56 The orthometalation of pyridine and substituted pyridines by [Ru 3 (CO) 12 ] has been previously observed, but these reactions require higher temperatures.…”

Reaction of FcCCC(O)R (Fc = ferrocenyl) with Ru3(CO)12 leading to unexpected nitro-group reduced ruthenoles and 1,2-CO-inserted triruthenium clusters

“…bonds. 2 To understand the related activated mechanisms, reactions of Ru 3 (CO) 12 with NHCs, 3 arenes, 4 alkenes 5 and alkynes 6 were extensively investigated. In recent years, some carbonyl ruthenium compounds formed via Ru 3 (CO) 12 and unsaturated hydrocarbons have been used in catalytic reactions.…”