Direct Oxidative Addition of Magnesium to Organic Halides

A. Direct Oxidative Addition of Magnesium to Organic Halides. 512... 

Unfortunately, the preparation of functionalized Grignard reagents via direct oxidative addition of magnesium metal to organic halides still suffers from severe limitations. This is mainly due to the intrinsic high reducing potential of magnesium metal. 

The order of reactivity of organic halides is I > Br > Cl > F. Although organic iodides are the most reactive, they produce more Wurtz coupling products through the radical oxidative addition process. Thus, it is usually advisable to use the chlorides or bromides, except in the case of aromatic iodides and methyl iodide. 1-Alkenyl Grignard compounds are obtained by the direct reaction of magnesium and vinylic halides in THF [6], but the reaction is not completely stereospecific and the retention of the stereochemistry of haloalkenes varies from 60-90% [7]. The difficulty associated... 

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