New homo- and hetero-dimetallic complexes bridged by diphenyl-2-pyridylphosphine and hydrides [(Cp*Ir)(μ-PPh2Py)(μ-H)2(MCp*)][OTf]n (3: M = Ir, n = 2; 4: M = Rh, n = 2; 5: M = Ru, n = 1) were synthesized. The reactions of 3 with terminal alkynes gave μ-vinyl complexes [(Cp*Ir)(μ-PPh2Py)(μ-H)(μ-C(R)=CH2)(IrCp*)][OTf]2 (6: R = H; 7: R = CO2Me; 9: R = Ph) and [(Cp*Ir)(μ-PPh2Py)(μ-H)(μ-CHCHR)(IrCp*)][OTf]2 (8: R = SiMe3; 10: R = Ph). The reactions of 4 with alkynes gave [(Cp*Ir)(μ-PPh2Py)(μ-H)(μ-C(R)=CH2)(RhCp*)][OTf]2 (11a: R = H; 12a: R = CO2Me; 13a: R = Ph), two of which are in equilibrium with [(Cp*Ir)(μ-PPh2Py)(μ-H)(μ-CH2=C(CO2Me))(RhCp*)][OTf]2 (12b) and [(Cp*Ir)(μ-PPh2Py)(μ-H)(μ-CH2=C(Ph))(RhCp*)][OTf]2 (13b) at 50 °C, respectively. The reactions of 5 with alkynes gave [(Cp*Ir)(μ-PPh2Py)(μ-H)(μ-CH2=C(R))(RuCp*)][OTf] (14b: R = CO2Me; 15b: R = Ph). Plausible pathways for the insertion of alkynes to the metal–hydride bonds and the interconversion of the μ-vinyl complexes are discussed. Structures of the cationic parts of 3, 8, 9, 13b, 14b and 15b have been confirmed by X-ray analysis.
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