Ethylzincation of Monosubstituted Alkenes Catalyzed by EtMgBr−Cl2ZrCp2 and Palladium-Catalyzed Cross Coupling of the Resultant Diisoalkylzinc Derivatives

The reaction of monosubstituted alkenes with 0.5 molar equiv of Et2Zn in the presence of a catalyst generated in situ by treatment of Cl2ZrCp2 with 2 molar equiv of EtMgBr produces regioselectively the corresponding diisoalkylzincs 1, generally in high yields. Their direct cross coupling with a variety of organic halides in the same reaction vessel can be achieved in good yields with a catalytic amount of a palladium complex.