Functionalization of 1-methyl-1H-imidazole-5-carboxylic acid at the C-2 position: efficient syntheses of 2-substituted t-butyl 1-methyl-1H-imidazole-5-carboxylates

A number of 2-substituted t-butyl 1-methyl-1H-imidazole-5-carboxylates, whi ch can be readily converted to the corresponding acids, were efficiently pr epared from t-butyl 2-bromo-1-methyl-1H-imidazole-5-carboxylate via bromine lithium exchange or palladium-catalysed coupling.