Selective C-3 and C-2 lithiation of 1-(2,2-diethylbutanoyl)indole

1-(2,2-Diethylbutanoyl)indole (1) can be lithiated regioselectively at C-3 by treatment with sec-BuLi–PMDTA in hexane at −78°C. In contrast, 1 is lithiated at C-2 with sec-BuLi–tert-BuOK in THF at −78°C. The generated C-3 and C-2 lithio species were trapped with a variety of electrophiles to give the corresponding substitution products.