Synthesis and X-ray crystallographic characterisation of the diphosphane bridged cluster [Ir4(CO)11PhPPPhlr4(CO)9(AuPEt3)2]
作者:J. Nicola Nicholls、Paul R. Raithby、Maria D. Vargas
DOI:10.1039/c39860001617
日期:——
Deprotonation of [Ir4(CO)11PPhH2] followed by oxidation with Ag[ClO4] in the presence of [AuPEt3]+ affords the cluster [Ir4(CO)11PhPPPhIr4(CO)9(AuPEt3)2], which has been shown by an X-ray analysis to contain an Ir4 and an Ir4Au2 unit linked by adiphosphane (PhPPPh) ligand.
Synthesis and structural characterization of the first transition metal cluster containing a PPh2AuPPh3 ligand, Ir4(CO)8(μ-CO)3(PPh2AuPPh3), and its conversion into Ir4(CO)9(μ-CO)(μ-PPh2)(μ-AuPPh3)
作者:Dario Braga、Fabrizia Grepioni、Fatima S. Livotto、Maria D. Vargas
DOI:10.1016/0022-328x(90)80184-2
日期:1990.7
Deprotonation of Ir4(CO)11PPh2H (1) in the presence of [AuPPh3][PF6] yields the novel species Ir4(CO)11(PPh2AuPPh3) (2), which possesses a tetrahedral framework bearing a terminally bound PPh2AuPPh3 ligand. When heated in toluene, 2 is converted into the phosphido species Ir4(CO)10(μ-PPh2)(μ-AuPPh3).
Kinetics of conversion of [Ir<sub>4</sub>(CO)<sub>11</sub>(PPh<sub>2</sub>AuPPh<sub>3</sub>)] into [Ir<sub>4</sub>(CO)<sub>10</sub>(µ-PPh<sub>2</sub>)(µ-AuPPh<sub>3</sub>)] and their structural characterization
作者:Fatima S. Livotto、Maria D. Vargas、Dario Braga、Fabrizia Grepioni
DOI:10.1039/dt9920000577
日期:——
Deprotonation of [Ir4(CO)11(PPh2H)] 1 in the presence of [Au(PPh3)]PF6 yields the novel species [Ir4(CO)11(PPh2AuPPh3)] 2 which possesses a tetrahedral framework bearing a terminally bonded PPh2AuPPh3 ligand. Changing the order of addition of the reagents results in the formation of [Ir4(CO)10(mu-PPh2)(mu-AuPPh3)] 4 with bridging phosphido and Au(PPh3)+ units. Reaction of 4 with PPh3 yields [Ir4(CO)9(PPh3)(mu-PPh2)(mu-AuPPh3)] 6, while with the more basic phosphine P(C6H4OMe-4)3 substitution of the PPh3 at the Au(PPh3)+ unit occurs producing [Ir4(CO)10(mu-PPh2)mu-AuP(C6H4OMe-4)3}]. Deprotonation of [Ir4(CO)10(PPh3)(PPh2H)] in the presence of [Au(PPh3)]PF6 yields [Ir4(CO)10(PPh3)(PPh2AuPPh3)], which undergoes rearrangement to 6. The kinetics of decarbonylation of compound 2 to give 4 has been investigated and a dissociative mechanism is suggested, confirmed by the activation parameters DELTA-H(double dagger) = 1 35.6 +/- 3.8 kJ mol-1 and DELTA-S(double dagger) = 81.2 +/- 10.9 J K-1 mol-1.