Novel alkyne and phosphaalkyne coupling on an Ir₄cluster: synthesis and molecular structure of [Ir₄(µ-CO)(CO)₇{µ₄-η³-Ph₂PC(H)C(Ph)PCBu^t}(µ-PPh₂)]

Abstract

The cluster compound [(p-H)Ir4(CO),(Ph2PCCPh)(p-PPh2)] 1 reacts with the phosphaalkyne ButCP to yield [Ir4(p-CO)(CO),{p~-113-Ph2PC(H)C(Ph)PCBut}(p-PPh2)] 3, containing the novel 2-phosphabutadienylphosphine fragment as a result of the coupling of ButCP with the diphenylphosphinoalkyne ligand and incorporation of the cluster bound H atom.

Synthesis and Structural Characterization of [Ir4(mu-CO)(CO)7{mu4-eta3-Ph2PC(H)C(Ph)PCBu t}(mu-PPh2)]: Alkyne-Phosphaalkyne Coupling and Formation of a Novel 2-phosphabutadienylphosphine Ligand

“…We report herein the first example of a phosphaalkyne-alkyne coupling reaction in the coordination sphere of a cluster compound, and describe the synthesis and characterization of [Ir4(µ-CO)(CO)7{µ4-η 3 -Ph2PC(H) C(Ph)PCBu t }(µ-PPh2)] 2, which contains the 2-phosphabutadienylphosphine chain. A preliminary communication of this work has appeared elsewhere 10 .…”

Carbon–carbon coupling on tetrahedral iridium clusters: X-ray molecular structures and multinuclear NMR studies of the two isomeric forms of [Ir4(CO)6(μ3-η2-HCCPh)(μ2-η4-C4H2Ph2)(μ-PPh2)2]

“…In compound 4, the peak at d 116.00 is correlated to the proton at d 5.73 (d), whereas those at d 108.00 and at d 90.00 are correlated to d 7.80 (m) and d 6.61 (d), respectively. In the room temperature 31 (7) Å ] in the molecular structure of compound 3. The dependence of the d 31 P for phosphido bridges on metal-metal interactions is well established [43].…”

“…doi:10.1016/j.jorganchem.2004.08.010 this tetranuclear cluster under thermolytic conditions with C 2 (COOMe) 2 , to yield [Ir 4 (CO) 8 {C 2 (COOMe) 2 } 4 ] [22], and with cod (cod = cyclooctadiene), to give the alkyne containing clusters [Ir 4 (CO) 5 (cod) 2 (C 8 H 10 )] and [Ir 7 -(CO) 12 (cod)(C 8 H 11 )(C 8 H 10 )] [23,24] all in very low yields, and that of the oxidation of [Ir 6 (CO) 15 ] 2À with ferrocinium in the presence of PhCCPh to yield [Ir 6 -(CO) 14 (l 3 -g 2 -HCCPh)] and [Ir 6 (CO) 12 (l 3 -g 2 -HCCPh) 2 ] [25]. The cluster [HIr 4 (CO) 10 (l-PPh 2 )] [26] has proven itself a good entry into tetranuclear iridium organometallic chemistry [27][28][29][30][31][32][33][34][35]. Its derivative [HIr 4 -(CO) 9 (Ph 2 PC"CPh)(l-PPh 2 )] (1) undergoes a selective rearrangement under mild conditions to give [Ir 4 -(CO) 8 (l 3 -g 2 -HCCPh)(l-PPh 2 ) 2 ] (2) [34].…”

Transformation of an η1-coordinated phosphaalkyne into a bridging phosphinidene ligand

“…Although some aspects of the interactions of phosphalkynes with metal clusters containing iron [9,10], ruthenium [11], osmium [12], rhenium [13], and iridium [14] clusters have been reported, reactions with late transition metal clusters have received far less attention. These clusters contain fewer valence electrons than those of the mid transition metals, and their reactivities are rather different [15].…”