Grignard reagents metal catalysis

The application of transition metal catalysis provided new opportunities to introduce diverse functionality to the diazepine ring system. Iron-catalyzed cross-coupling of Grignard reagents with the imidoyl chloride 40 provided a convenient and efficient method for substituting the heterocyclic ring (Scheme 9) <20060L1771>. 

Transition metal catalysis has been applied in this process. In the presence of 2mol% FeCb, low reactive aryl chlorides rapidly give aryl Grignard reagents in excellent yields (Scheme 2).10... 

This reaction is superficially understood as a formal delivery of H-MgX element from a Grignard reagent to an olefin under catalysis of such a transition metal complex (Scheme 3). 

Recent developments in catalysis at the atomic level are described. The use of transition metal halides which form intermediate metal n-complexes can promote both the catalytic and stoichiometric coupling of aryl Grignard reagents, the stereospecific coupling of 1,2 disubstituted vinyl groups and the double coupling of ethylene to dimers of butadiene. 

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