Synthesis of Novel Allene-Coordinated, Phosphido-Bridged Ru₂Pt Clusters Involving Enyne to Allene Transformation

Abstract

Microwave irradiation of a toluene solution of the diyne FcC 2 C 2 Ph and Ru 3 (CO) 12 yields the [Ru(CO) 3 (η 4ruthenole)] derivatives 1a−f, which differ in relative positions of the uncoordinated alkyne group. Upon treatment with Pt(PPh 3 ) 2 C 2 H 4 , the ruthenoles 1a−c, containing a single free CC unit at the α position with respect to the ring Ru metal, yield the novel allene-coordinated, phosphido-bridged Ru 2 Pt clusters 3a−c along with their phosphine-substituted derivatives 4a−c. Under similar reaction conditions, isomers 1d,e, which are devoid of any free CC unit at the α position, and 1f, having free CC units at both α positions, form only their phosphine-substituted derivatives 4d−f. The formation of Ru 2 Pt clusters from ruthenole complexes involves cleavage of the P−C bond of the phosphine and migration of the resulting phenyl group onto the free alkyne, which leads to enyne to allene transformation.

Crystal structure of [μ-1κ2 C 1,C 4:2(1,2,3,4-η)-1,2,3,4-tetraphenylbuta-1,3-diene-1,4-diyl]bis(tricarbonylosmium)(Os—Os)

“…Metallacyclopentadiene complexes, known as metalloles, with the formula (-4 -C 4 R 4 )M 2 (CO) 6 are typically produced by C-C bond-coupling reactions of alkynes with group 8 metal carbonyls (Mathur et al, 2014). These metalloles have been shown to adopt one of two possible geometries in the solid state, i.e.…”

“…one in which the carbonyl ligands of the M 2 (CO) 6 units are eclipsed in a so-called sawhorse conformation, or one in which the carbonyls are staggered with one CO semibridging the metal-metal bond. Ferroles (M = Fe) almost always adopt the staggered non-sawhorse conformation (Kumar et al, 2014;Iyoda et al, 1997;Jeannin et al, 1994;Heim et al, 1992;Daran & Jeannin, 1984), while ruthenoles (M = Ru) display an equal propensity to adopt either the sawhorse or the nonsawhorse conformation (Yang, 2014;Mathur et al, 2008Mathur et al, , 2014Tunik et al, 1997). Only two osmole (M = Os) complexes have been examined by X-ray crystallographic analysis, and both of them exhibit the sawhorse conformation.…”

CO-free, aqueous mediated, instant and selective reduction of nitrobenzeneviarobustly stable chalcogen stabilised iron carbonyl clusters (Fe3E2(CO)9, E = S, Se, Te)

“…5 Nevertheless, due to the high catalytic potential of Fe(CO) 5 , it has been extensively used for various carbonylation reactions as well as as for high-nuclearity clustere formations. [6][7][8][9][10][11] Electron-transfer, 12 hydrogenation, 13 hydride transfer 14 and electrochemical methods 15 are some of the important available methodologies to furnish distinct amines by utilizing a nitro precursor. The reduction of nitrobenzene has gained tremendous interest due to its hazardous effect on the environment.…”

“…25 Metal carbonyls and clusters have been used for a wide range of catalysis: in particular, for carbonylation, 26 C-C coupling, 27 hydroformylation, 28 hydroesterication, 29 reduction of nitroaranes [30][31][32] and many more value-added organic transformations. [6][7][8][9][10][11] Initially (Scheme 1), Pittman and co-workers in 1979 utilised Rh 6 (CO) 12 for nitro reduction. 33 Later, in 2014, Kaneda and co-workers used a composite dendrimer of Rh 5 carbonyl cluster and polyamine composite for nitro reduction.…”

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

“… 13 Recently, P. Mathur reported a series of [Ru(CO) 3 (η 4 -ruthenole)] derivatives during the reaction of Ru 3 (CO) 12 with FcC 2 C 2 Ph (Fc = ferrocenyl). 14 Therefore, the reactions of Ru 3 (CO) 12 with different acetylenes can afford a variety of unexpected products, 10–15 which motivates us to explore the activated mechanisms via experienced sophisticated transformations of alkynes.…”