Reactions
1. Precursor to catalysts for the asymmetric hydrogenation of tri- and tetrasubstituted olefins.
2. Precursor to catalyst for enantioselective reduction of imines.
3. Precursor to catalyst for allylic alkylation.
4. Precursor to catalyst for allylic amination and etherification.
5. Precursor to catalyst for the reaction of aroyl chlorides with internal alkynes to produce substituted naphthalenes and anthracenes.
6. Ir-catalyzed addition of acid chlorides to terminal alkynes.
7. Intramolecular hydroamination of unactivated alkenes with secondary alkyl- and arylamines.
8. Enantioselective [2+2] cycloaddition.
9. Silyl-directed, Ir-catalyzed ortho-borylation of arenes.
10. Ir-catalyzed cross-coupling of styrene derivatives with allylic carbonates.
11. Transfer hydrogenative C-C coupling
Uses
Chloro(1,5-cyclooctadiene)iridium(I) dimer is widely used as a precursor to other iridium complexes, which finds application in homogeneous catalysis like carbonylation, hydrosilylation, hydrofomylation, asymmetric allylic substitutions, metathesis and chiral catalysis reactions. It is involved in the preparation of Crabtree's catalyst, which is used for hydrogenation and hydrogen-transfer reactions.
Synthesis
A solution of 6 mL of 1,5-cyclooctadiene in 35 mL of ethanol and 20 mL of water is added to 2.0 g of IrCl3.3H2O in a round-bottomed flask. The mixture is refluxed under nitrogen for 24 h when an orange-red product precipitates from the solution. The mixture is cooled to rt, and Di-μ-chlorobis(1,5-cyclooctadiene)diiridium(I) (Chloro(1,5-cyclooctadiene)iridium(I) dimer) is collected by filtration, washed with cold methanol, and dried in vacuo at 25 °C for 8 h.
