Low-pressure selective hydroformylation of 2,3- and 2,5-dihydrofuran with a rhodium catalyst. Unexpected influence of the auxiliary ligand tris(o-t-butylphenyl) phosphite

Hydroformylation of 2,3- and 2,5-dihydrofuran has been achieved in excellent yields and good selectivities under mild conditions using [Rh2{µ-S(CH2)3NMe2}2(cod)2] and suitable auxiliary ligands (cod = cyclo-octa-1,5-diene).