The preparation of novel organozinc reagents using highly reactive zinc

Highly reactive zinc was prepared by the lithium naphthalenide reduction of zinc halides. This highly reactive zinc readily undergoes oxidative addition to alkyl, aryl and vinyl iodides and bromides under mild conditions to generate the corresponding organozinc compounds in excellent yields. Significantly, the reactions will tolerate a wide spectrum of functional groups, such as ester, nitrile, chloride, and remote ketone on the organic halides. Accordingly, this approach can now be used to prepare a wide variety of highly functionalized organozinc compounds. In the presence of CuCN$\cdot$2LiBr complexes, the organozinc compounds cross-couple with acid chlorides, conjugatively add to $\alpha,\beta$-unsaturated ketones, and regioselectively undergo S$\sb{\rm N}$2$\sp\prime$ substitution reactions with allylic halides and tosylates. They also cross-couple with aryl or vinyl halides with Pd(0) catalysts