Using Lithium-, Sodium-, or Magnesium-Iron Mixed-Metal Bases

4 Using Lithium-, Sodium-, or Magnesium-Iron Mixed-Metal Bases 

SCHEME 27.24 Benzene dideprotometalation using a sodium-iron base. 

Salt-activated Fe(TMP)2-2MgCl2-4LiCl was successfully used in THF at room temperature to convert activated 1,3- and 1,4-disubstituted arenes into the corresponding diaryliron(It) species. The latter were cross-coupled under nickel catalysis with alkyl iodides and bromides or even benzyl chloride. The reaction tolerates a large range of functional groups (Table 27.9) [22]. 

TABLE 27.9 Activated Benzenes Deprotometalation Using a Lithium-Magnesium-Iron Base and Subsequent Nickel-Cataiyzed Aikylation 

SCHEME 27.25 Anisole deprotometalation using a lithium-iron base and subsequent interception with iodine and pivalaldehyde. 

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