Close examination of 1-hexene hydroformylation reactions catalyzed by cobalt carbonyl/triarylphosphine(PPh3 or P(p-MeC6H4)3, linked to PPh2-functionalized polystyrene or PPh2-functionalized (aryloxy) phosphazenes) has revealed a time-dependent decrease in catalytic activity due to a cobalt-mediated phosphorus-carbon bond cleavage. Benzene and benzyl alcohol were detected as the cleavage products. When olefin is omitted from the reaction, R2PH is formed. The detection of p-MeC6H4CH2OH indicates that oxidative addition of the P-aryl bond to Co is at least a partial contribution to the process. These results are relevant to transition-metal-triarylphosphine catalysis in general and put a new perspective on “immobilized” homogeneous catalysis.
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry