Arene-ruthenium(II) and osmium(II) complexes as catalysts for nitrile hydration and aldoxime rearrangement reactions

A Comprehensive Analysis of the Metal–Nitrile Bonding in an Organo-Diiron System

“…( I ) R = Me, Ph, 4-C 6 H 4 Br [ 13 ]. ( II ) X = H, OH, CH 2 OH, NH 2 , Br, Cl [ 15 ]. ( III ) R = Et, Ph, 4-C 6 H 4 Me, 4-C 6 H 4 OMe, 4-C 6 H 4 NMe 2 , 4-C 6 H 4 NO 2 [ 16 ].…”

“…They most commonly behave as monodentate ( end-on ) ligands, and have been widely employed as weakly coordinating agents in complexes of low- to middle-valent transition metals, since their substitution by more strongly coordinating ligands is a convenient strategy to access a multitude of derivatives, catalysts and materials [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 ]. Furthermore, nitrile ligands are usually susceptible to nucleophilic attack [ 12 , 13 , 14 ] and may be engaged in a great variety of chemical transformations mediated by the adjacent metal centre, either catalytic [ 15 , 16 , 17 , 18 ] or stoichiometric [ 12 , 19 , 20 , 21 , 22 , 23 ].…”

Arene-Osmium(II) Complexes in Homogeneous Catalysis

“…The catalytic hydration of nitriles represents an efficient and atom economical route to synthesize primary amides, that are important structural elements in organic chemistry. A huge number of catalytic systems have been developed during the last decades, with those involving ruthenium being by far the most abundant since they usually feature an outstanding activity and functional group compatibility [107][108][109][110][111]. Although osmium has been comparatively much less studied, some arene-osmium(II) derivatives have been found to promote these reactions with activities comparable, or even superior, to those of related ruthenium-based systems [111].…”

“…A huge number of catalytic systems have been developed during the last decades, with those involving ruthenium being by far the most abundant since they usually feature an outstanding activity and functional group compatibility [107][108][109][110][111]. Although osmium has been comparatively much less studied, some arene-osmium(II) derivatives have been found to promote these reactions with activities comparable, or even superior, to those of related ruthenium-based systems [111]. This was evidenced for the first time by Nazarov, Hartinger, and co-workers in 2008 with complex 50, which managed to convert trichloroacetonitrile into trichloroacetamide with the same effectiveness as its ruthenium analog performing the hydration process in pure water at 75 • C in the absence of any additive (Scheme 22) [112].…”

Dichloro(η6-p-cymene)(P,P-diphenyl-N-propyl-phosphinous amide-κP)ruthenium(II)

“…This fact prompted us to synthesize a representative complex containing one of these ligands, namely [RuCl 2 (η 6 -p-cymene)(PPh 2 NH n Pr)] (2), and study its behavior in the hydration of the model benzonitrile substrate. A half-sandwich (η 6 -p-cymene)-ruthenium(II) complex was chosen as the [RuCl 2 (η 6 -p-cymene)] fragment represents an excellent platform for the screening of ligands [15]. Details on the preparation, characterization and catalytic activity of the novel ruthenium(II) complex 2 are herein presented.…”