Synthesis and reactivity of osmium and ruthenium PBP–LXL boryl pincer complexes. (14th December 2016) - McQueen, Caitlin M.A.
Graphical abstract: The first examples of osmium boryl pincer complexes and their ligand substitution chemistry are described alongside those of the ruthenium analogue. Abstract: The reaction of HB(NCH2 PPh2 )2 C6 H4 -1, 2 with [OsCl(Ph)(CO)(PPh3 )2 ] affords the boryl pincer complex [OsCl(CO)(PPh3 ){B(NCH2 PPh2 )2 C6 H4 }]. This complex, and its ruthenium analogue were observed to undergo various reactions involving substitution of the chloride and triphenylphosphine co-ligands to give new complexes [MCl(CO)(CNC6 H2 Me3 ){B(NCH2 PPh2 )2 C6 H4 }] (M = Ru, Os), [MH(CO)(PPh3 ){B(NCH2 PPh2 )2 C6 H4 }] (M = Ru, Os) and [Ru(κ 2 - S, S ′ - S2 CNEt2 )(CO){B(NCH2 PPh2 )2 C6 H4 }]. The ruthenium complex [RuH(CO)(PPh3 ){B(NCH2 PPh2 )2 C6 H4 }] was found to react with carbon disulfide and carbon monoxide to give the complexes [Ru(κ 2 - S, S ′-S2 CH)(CO){B(NCH2 PPh2 )2 C6 H4 }] and [RuH(CO)2 {B(NCH2 PPh2 )2 C6 H4 }], respectively, the latter as an apparently interconverting mixture of cis and trans dicarbonyl isomers.