Abstract Phenolic groups with pKa≤ 8 (due to the presence of electron withdrawing groups in the orho-or para-position) can be alkylated selectively with Li2CO3/alkyl halide/DMF; less acidic phenolic groups are unreactive. Even though chelated phenolic/enolic functions have unexpectedly high experimental pKa′ s (∼ 10), they can be alkylated with this reagent combination.
