New rhodium complexes with P,N-ligands possessing a hydroxy or methoxy group. Synthesis, characterization and application to hydroformylation of styrene

Two new cationic rhodium(I) complexes containing a phosphino amino alcohol ligand and a methoxy amino phosphine, respectively, have been prepared. Acc ording to IR and NMR data the ligands are P,N-bonded and coordination of th e hydroxy or the methoxy group to the metal does not take place. The comple xes were applied to the hydroformylation of styrene and displayed a quantit ative chemoselectivity for aldehydes with a very good branched:linear ratio . The reaction rate is higher using the complex possessing the methoxy grou p as opposed to the hydroxy group. (C) 1999 Elsevier Science S.A. All right s reserved.