The chlorocarbonyl bis-[butylphenyl (meta-sulfonate-phenyl)phosphine] rhodium (I) complex shows catalytic hydroformylation activity in toluene/water biphasic medium for 1-hexene, cyclohexene, 2,3-dimethyl-2-butene and 2-methyl-2-pentene, their binary mixtures and a real Venezuelan naphtha, under standardized reaction conditions (1000 psi of syngas (1:1 H-2/CO), 100 degrees C, substrate/catalyst molar ratio (600:1) and 4 h reaction time), obtaining high percent conversion to oxygenated products.