Iridium allenylidene

Although less widespread than the rhodium cognate species, iridium allenylidenes are well documented and have been known since 1997 when the first compounds featuring the allenylidene, Ir=C=C=CRRi, moiety were independently obtained by Oro, " Werner,and their co-workers. While not isolated in the solid state or even detected in solution, the existence of an iridium allenylidene was previously invoked by O Connor et al. to... 

Reaction of [Ir(OMe)(PR3)(diene)] (R = Pr 3, Cy diene = COD, TFB 586) with HC=CCPh20H results in the formation of the alkynyl complexes [Ir(C CCPh20H)(PR3)(diene)] 587 which yield the iridium allenylidenes [Ir(C=C=CPh2)(PR3)(diene)] 588 after reaction with HBF-OEt2 (Scheme 84). ... 

Scheme 24 Coupling of allenylidene ligands with terminal aUcynes at iridium...

Iridium-carbon multiple bonds allenylidene complexes, 7, 355 carbene complexes, 7, 344 carbyne complexes, 7, 361 higher cumulenylidene complexes, 7, 358 vinylidene complexes, 7, 352 Iridium-carbon single-bonded complexes alkenyl complexes, 7, 319 alkyl and aryl complexes, 7, 303 in C-C bond-forming catalysis, 7, 335 characteristics, 7, 303... 

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