Naphthalene-catalysed lithiation of functionalized chloroarenes: Regioselective preparation and reactivity of functionalized lithioarenes

Article abstract of DOI:10.1016/S0040-4020(01)80314-8

The lithiation of different functionalized chloroarenes (dichlorobenzenes 1 and 3, mono and dichlorophenols 9 and 14, and chloropivalanilides 18) in the presence of a catalytic amount of naphthalene leads to the corresponding functionalized lithioarenes, which react with electrophiles to give the expected polyfunctionalized aromatic molecules 2, 4, 10, 19, 21, 22 and 24 in a regioselective manner. In the case of starting from chlorinated phenols or anilides a deprotonation of the functional group is carried out prior to the lithiation process; only for 2-chloropivalanilide 18o a coupling reaction leading to 2-n-butylpivalanilide is observed when an excess of n-butyllithium is used in the deprotonation step.