Abstract Small amounts of achiral polyether binders are employed to enhance the enantioselectivity of the hydroformylation of an array of diversely substituted substrates (increase of up to 62% ee for vinyl acetate) mediated by chiral rhodium complexes derived from the α, ω-bis (phosphite)–polyether ligands 1. To the best of our knowledge, this study represents an unprecedented successful example of the positive regulation of ...