0000000000534950
AUTHOR
Isabel Solana
C—br insertion reactions in rhodium and iridium compounds containing an ortho-halo-arylphosphine. X-ray structures of two ortho-metallated compounds of formula IrX2[P(C6F4)Ph2][P(o-BrC6F4)Ph2], (X = Cl, Br)
Abstract A comparative study of the reaction of rh and ir complexes with the ortho-bromo-arylphosphine PCBr [PCBr = P(o-BrC6F4)(C6H5)2], is presented. Various PCBr complexes of Ir(I) and Rh(I) undergo rapid insertion of the metal atom into a CBr bond provided the phosphine is coordinated in a η2-mode (Pbr). If the Br coordination is substituted by a superior ligand such as CO or an olefin, no reaction occurs under normal conditions. PCBr complexes of the tervalent metals require a two-electron reduction step prior to the ortho-metallation reaction. Most intermediates were characterized by chemical and spectroscopic analysis. Two intermediates of general formula IrX2(η2-PC)(η-PCBr), [PC = …
Synthesis of new orthometallated iridium(III) compounds by chemical and electrochemical methods
Abstract Replacement of one phosphine ligand in IrCl 3 (η 2 -PCBr)(η 1 -PCBr) ( 1 ) (PCBr = P( o -BrC 6 F 4 )Ph 2 ), by various P-donor ligands has given compounds of stoichiometry IrCl 3 (η 2 -PCBr)L ( 3 : L = PMePh 2 ; 4 : L = P( p -MeC 6 H 4 ) 3 ; 5 : L = P(OMe) 3 , 6 : L = P(OPh) 3 ). All of these show two irreversible reduction peaks in the range −1.1, −1.3 and ca. −2.0 V. The electrochemical reduction of compound 1 at −1.5 V (at 0°C) leads to a very reactive iridium(I) species, probably IrCl(PCBr) 2 , which undergoes intramolecular orthometallation at room temperature. Three compounds are obtained as the results of this chemical conversion: IrBr 2 (PC)(PCBr) ( 7 ), IrCl 2 (PC)(PCBr) (…
Preparation and study of silver maleonitriledithiolate complexes
Abstract This paper reports the reaction of Ag2(mnt) and [(NEt4)Ag(mnt)] (mnt2− = maleonitriledithiolate) with PPh3 and 1,2-bis(diphenylphosph