Biphase hydroformylation catalyzed by rhodium in combination with a water-soluble pyridyl- triazole ligand

Abstract [RhCl(COD)] 2 in combination with a water soluble sulphonated pyridyl-triazolyl N,N -bidentate ligand efficiently catalyzes styrene and 1-hexene hydroformylation in water/organic solvent biphasic systems. The catalyst displays a good activity affording mixtures of linear and branched aldehydes with complete chemoselectivity. The aqueous catalytic phase may be recycled four times giving complete substrate conversion by 18 h. Mercury-poisoning experiments and transmission electron microscopy indicate that, after the first catalytic run, rhodium is present in the aqueous phase in nanoparticle form.