The Rh(III) and Ir(III) pentamethylcyclopentadienyl compounds [M(Cp*)(kappa(2)-Ph(2)Bp)Cl] (M = Rh, 1; M = Ir, 4) were readily prepared from interaction of the salt K[Ph(2)Bp] (Ph(2)Bp = diphenylbis(pyrazolyl)borate) and the [M(Cp*)Cl-2](2) dimer precursors in dichloromethane under anhydrous conditions. When the same reactions were carried out in non-anhydrous conditions by using acetonitrile as solvent, we observed, in the case of Rh, both B-N bond hydrolysis and Rh-C(Ph) bond activation with the formation of the hydroxy(pyrazolyl)borate complex [Rh(Cp*)(Ph){kappa(2)-(pz)(OH)BPh2}] (2). In contrast, in the case of Ir only B-N hydrolysis was observed and the ionic species [Ir(Cp*)(Hpz){kappa(2-)(pz)(OH)BPh2}]Cl (5) was obtained, upon coordination of the liberated Hpz. Additionally, by reaction of 1 with AgClO4 in acetonitrile, the ionic [Rh(Cp*)(Ph){kappa(2)-(pz)(OH)B(OH)}]ClO4 (3) was isolated. Complexes 1-3 and 5 have been structurally characterized by X-ray crystallography. Spectral studies have been performed for all species, together with a computational DFT modeling investigation. A decomposition mechanism for the diphenylbis(pyrazolyl)borate ligand in the different complexes is proposed.
Riccardo Pettinari, Claudio Pettinari, Fabio Marchetti, Magda Monari, Edoardo Mosconi, Filippo De Angelis (2013). Boron Functionalization and Unusual B–C Bond Activation in Rhodium(III) and Iridium(III) Complexes with Diphenylbis(pyrazolylborate) Ligands (Ph2Bp). ORGANOMETALLICS, 32, 3895-3902 [10.1021/om400375j].
Boron Functionalization and Unusual B–C Bond Activation in Rhodium(III) and Iridium(III) Complexes with Diphenylbis(pyrazolylborate) Ligands (Ph2Bp)
MONARI, MAGDA;
2013
Abstract
The Rh(III) and Ir(III) pentamethylcyclopentadienyl compounds [M(Cp*)(kappa(2)-Ph(2)Bp)Cl] (M = Rh, 1; M = Ir, 4) were readily prepared from interaction of the salt K[Ph(2)Bp] (Ph(2)Bp = diphenylbis(pyrazolyl)borate) and the [M(Cp*)Cl-2](2) dimer precursors in dichloromethane under anhydrous conditions. When the same reactions were carried out in non-anhydrous conditions by using acetonitrile as solvent, we observed, in the case of Rh, both B-N bond hydrolysis and Rh-C(Ph) bond activation with the formation of the hydroxy(pyrazolyl)borate complex [Rh(Cp*)(Ph){kappa(2)-(pz)(OH)BPh2}] (2). In contrast, in the case of Ir only B-N hydrolysis was observed and the ionic species [Ir(Cp*)(Hpz){kappa(2-)(pz)(OH)BPh2}]Cl (5) was obtained, upon coordination of the liberated Hpz. Additionally, by reaction of 1 with AgClO4 in acetonitrile, the ionic [Rh(Cp*)(Ph){kappa(2)-(pz)(OH)B(OH)}]ClO4 (3) was isolated. Complexes 1-3 and 5 have been structurally characterized by X-ray crystallography. Spectral studies have been performed for all species, together with a computational DFT modeling investigation. A decomposition mechanism for the diphenylbis(pyrazolyl)borate ligand in the different complexes is proposed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
