Cyclometalation reactions on rhodium(I). Evidence for a chelate effect and competing C-H and C-O oxidative additions
The ligand Ph2PC6H4(CH2N(Me)CO(Et)) reacts with (bis(diphenylphosphino)butane) (2,5-norbornadiene)rhodium tetrafluoroborate (2a) and (bis(diphenylphosphino)ethane)(2,5-norbornadiene) rhodium tetrafluoroborate (2b) at room temperature in the presence of hydrogen to displace the norbornadiene and give the chelate complexes 3a,b, in which the phosphorus and the oxygen atoms are coordinated to give an
