Our initial study began with the reaction of 2-iodoaniline (1a) and ethyl buta-2,3-dienoate (2a) in the presence of 1.5 equivalents of K 2 CO 3 in 1,4-dioxane at 120 ˚C. The desired ethyl 2-methyl-1H-indole-3-carboxylate (3aa) was obtained in 32% conversion and 28% yield in the reaction catalyzed by CuI after 12 hours (Table [¹] , entry 1). When a mixture of 1a and 2a in dioxane was heated (100 ˚C, 8 h; t 1 ) and cooled to room temperature, then a catalytic amount of ...
