Arylation with Electrophilic C-Centered Radicals

N-methyl-2-formylpyrrole and subsequent H-abstraction by radical R eventually delivers the substituted pyrrole 79. 

Homolytic aromatic substitution can also be performed with electrophihc het-eroatom-centered radicals. The radical amination of arenes with electrophilic diaUcyl aminyl radical cations represents a valuable method for the preparation of aniUne derivatives [2e, 111a]. The radical cations (R2HN ) are generally prepared from the corresponding N-chloroamines in an acidic medium, using catalytic amounts of a metal salt [Fe(II)-, Ti(III)-, Cu(I)- and Cr(II)-salts]. The reaction func- 

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