Organomagnesium reagents functionalized

While the synthesis of fnnctionalised secondary alcohols and amines can be achieved withont catalyst by the addition of organolithium and organomagnesium reagents to C=N and C=0 gronps, these methods lack a significant functional group tolerance. In order to overcome this limitation and access to more functionalised compounds, the catalytic arylation of aldehydes and imines has been extensively studied [2]. 

Organomagnesium reagents, which can serve as the nucleophiles in the Kumada coupling, are easy to make and many of them are commercially available. Even though some Kumada reactions can be run at room or lower temperature, many functional groups are not tolerant of Grignard reagents. Nonetheless, in the synthesis of thienylbenzoic acid 24, the carboxylic acid moiety did survive the reaction conditions [25],... 

This iodine-magnesium exchange can also be performed with heterocyclic iodides, such as the functionalized pyridine 16 [21] or the iodouracil derivative 17 (Scheme 2.5) [22]. In both cases, the intermediate organomagnesium reagent can... 

The transition metal catalyzed carbon-carbon bond formation between organomagnesium reagents and aryl (vinyl) halides has been one of the pioneering entries into cross-coupling chemistry. The reaction has been widely utilized since than in azine chemistry,22 with the limitation that the functional group tolerance of Grignard reagents is only moderate. Here only some of the more recent developments will be mentioned. 

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