Aryl halides organomagnesium compound

Grignard reagent (Section 14.4) An organomagnesium compound of the type RMgX formed by the reaction of magnesium with an alkyl or aryl halide. 

The position of the equilibrium depends upon the solvent and the identity of the specific organic group, but in ether lies well to the left for simple aryl-, alkyl-, and alkenylmagnesium halides.21 Solutions of organomagnesium compounds in diethyl ether contain aggregated species.22 Dimers predominate in ether solutions of alkylmagnesium chlorides. 

C-Alkylations have been performed with both support-bound carbon nucleophiles and support-bound carbon electrophiles. Benzyl, allyl, and aryl halides or triflates have generally been used as the carbon electrophiles. Suitable carbon nucleophiles are boranes, organozinc and organomagnesium compounds. C-Alkylations have also been accomplished by the addition of radicals to alkenes. Polystyrene can also be alkylated under harsh conditions, e.g. by Friedel-Crafts alkylation [11-16] in the presence of strong acids. This type of reaction is incompatible with most linkers and is generally only suitable for the preparation of functionalized supports. Few examples have been reported of the preparation of alkanes by C-C bond formation on solid phase, and general methodologies for such preparations are still scarce. 

The coupling of Grignard reagents with alkyl, vinyl or aryl halides under Ni-catalysis provides an economic transformation, but the reaction is limited to halide partners that do not react with organomagnesium compounds. One example is in the industrial-scale production of styrene derivatives, and the Kumada Coupling is the method of choice for the low-cost synthesis of unsymmetrical biaryls. 

Transition metal-catalyzed cross-coupling reaction has become the most important method for the formation of aryl-aryl bonds. The reaction of aryl halides and sulfonates with organomagnesium compounds is usually referred... 

Catalysed cross-coupling of organomagnesium compounds with vinylic and aryl halides... 

Reactions of organomagnesium compounds with sulfoxides often result in ligand exchange [31], and may be complicated by a- or ortho metallation. However, in some cases, notably with 2-pyridyl aryl sulfoxides, reactions with arylmagnesium halides give useful yields of products from displacement of the aryl sulfoxido group [32, 33], e.g. [32]... 

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