Cycloocta-1,5-diene complexes iridium

The complex has enjoyed relatively little use in organic synthesis. For iridium-catalyzed homogeneous hydrogenation of alkenes, Crabtree s iridium complex ((1,5-Cycloocta-diene)(tricyclohexylphosphine)(pyridine)iridium(I) Hexafluoro-phosphate) is generally preferred, although this readily prepared Ir complex is active. It is more reactive than its rhodium counterpart in the catalytic isomerization of butenyl- to allylsilanes. ... 

A polymer-bound form of the homogeneous iridium phosphine complex [(1,5-cycloocta-diene)Ir(PPh3)2]PF6 t6T> has been prepared by stirring together [(l,5-cyclooctadiene)Ir... 

The mechanistic basis of iridium-complex-catalyzed enantioselective hydrogenation is less secure than in the rhodium case. It is well known that square-planar iridium complexes exhibit a stronger affinity for dihydrogen than their rhodium counterparts. In earlier studies, Crabtree et al. investigated the addition of H2 to their complex and observed two stereoisomeric intermediate dihydrides in the hydrogenation of the coordinated cycloocta-1,5-diene. The observations were in contrast to the course of H2 addition to Ms-phosphine iridium complexes [69]. 

Cyclometallapolyselanes, 27 59 Cyclometallation reactions, 26 171 Cycloocta-1,5-diene, iridium complex, 26 122, 27 23... 

Iridium complexes, such as [IrCl(COD)]2, (COD, cycloocta-1,5-diene) also catalyze Intramolecular Alder-ene type cycioisomerizations 1,6-enynes to give cyclic 1,4-dienes. Shibata et al. [32] demonstrated the increased efficiency of this catalyst system in an ionic liquid over toluene. Iridium(I)-catalyzed Alder-ene cycioisomerizations of an alkynoyl cyclohexadienyl ester or Af-tosyl amide have been shown to furnish spirocyclic products [33]. 

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