Novel rhodium complexes with N-pyrrolylphosphines: attractive precursors of hydroformylation catalysts

Abstract

New rhodium(I) complexes with N-pyrrolylphosphine ligands of formula [Rh(acac)(CO){P(NC 4 H 4 ) 3 }] 1a, [Rh(acac)(CO){PPh(NC 4 H 4 ) 2 }] 1b, [Rh(acac)(CO){PPh 2 (NC 4 H 4 )}] 1c, [Rh(acac){P(NC 4 H 4 ) 3 } 2 ] 2a, [Rh(acac){PPh(NC 4 H 4 ) 2 } 2 ] 2b and [Rh(acac){PPh 2 (NC 4 H 4 )} 2 ] 2c (acac = acetylacetonate) have been found to be precursors of very active and selective hydroformylation catalysts as [RhH(CO){P(NC 4 H 4 ) 3 } 3 ] 3a, [RhH(CO){PPh(NC 4 H 4 ) 2 } 3 ] 3b and [RhH(CO){PPh 2 (NC 4 H 4 )} 3 ] 3c respectively, which at 60 °C and 10 atm H 2 –CO produce 80–90% of aldehydes with n:iso 3–31:1.