The rhodium-catalyzed asymmetric 1,4-addition of organoboron reagents is developing quickly. The reaction can be carried out in an aqueous solvent and the enantioselectivity is very high, in most cases over 90% ee, at a reaction temperature of around 100°C. Thus, this reaction provides the best method for enantioselective introduction of aryl and alkenyl groups to β position of these electron deficient olefins.