Rhodium catalyst bearing 2,2'-bis(dipyrrolyphosphinooxy)1,1'-(+/-)-binaphthyl (ligand 1) shows high regioselectivity and activity for the hydroformylation of 2-octene. The introduction of a pyrrolyl group in the ligand greatly improves the yield of the linear aldehyde. The regioselectivity is up to 97.5% under mild conditions (100 degrees C, 0.7 MPa H-2/CO).