Novel water-soluble ligands were prepared in high yields by condensation of various amino acids with tris(hydroxymethyl)phosphane. Rhodium complexes of these ligands, formed in situ, were tested in two-phase hydroformylation of propylene. Selectivity observed with these ligand systems is easily controlled by altering the pH of the reaction mixture. (c) 2007 Elsevier B.V. All rights reserved.