| Abstract
| - C−H activation of acetophenone and cyclic and acyclic α,β-unsaturated ketones or estersoccurs with [IrH2(acetone)2(PPh3)2]+. In the case of acyclic α,β-unsaturated ketones or esters,the β-C−H bond was activated to afford iridafuran hydrides as cyclometalation products.For cyclopentenone, a cyclic α,β-unsaturated ketone, the C−H activation affords anη5-hydroxycyclopentadienyl iridium hydride. The activation of the ortho C−H bonds inacetophenone affords orthometalated products structurally related to the iridafuran hydrides.Plausible mechanisms are proposed for reactions in each case. In particular, the formationof iridafurans is believed to proceed by a mechanism analogous to that previously proposedfor the RuH2(CO)(PPh3)3-catalyzed Murai reaction.
- Acetophenone and cyclic and acyclic α,β-unsaturated ketones react differently with [IrH2(acetone)2(PPh3)2]+ in refluxing acetone. For α,β-unsaturated ketones, the products are iridafuran hydrides. The cyclometalation of acetophenone gives an iridium(III) aryl hydride. The C−H activation of cyclopentenone affords an iridium(III) hydroxylcyclopentadienyl hydride.
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