Water/MAO acceleration of the zirconocene-catalyzed asymmetric methylalumination of alpha-olefins

[GRAPHICS] The zirconocene-catalyzed enantioselective methylalumination of terminal al kenes is greatly accelerated in the presence of water. Terminal olefins tha t are inert under the standard conditions can be readily methylated in good yields and with good to high enantioselectivities. Furthermore, methylalum inoxane is also shown to accelerate the reaction, albeit at a lesser rate.