Scope
DOM has been applied to the synthesis of enantiopure benzyl amines in scheme 3, which involves ortho-lithiation of tert-butyl phenyl sulfoxide. On approach to the lithium intermediate, the bulky tosyl group on the imine electrophile is responsible for the asymmetric induction taking place.
In another application DOM is applied in placing a bulky tert-butyl group in an ortho position (scheme 4). The lithiation is a nucleophilic aromatic substitution and the subsequent reaction to the sulfoxide an electrophilic aromatic substitution. In the final step tert-butyllithium acts as a nucleophile in another nucleophilic aromatic substitution through an anionic intermediate.
DoM has also been applied combined with a Suzuki reaction in a one-pot synthesis :
DOM has also been used with thiophenols to prepare compounds that are useful as hindered ligands.
Read more about this topic: Directed Ortho Metalation
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