ethyl 3-ethyl-1H-indole-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of phenylhydrazine (1.0 g, 6.92 mmol) in absolute ethanol (50 mL) was placed in an oil bath at 60° C. and a reflux condenser attached. Ethyl 2-oxopentanoate (1.0 g, 6.94 mmol) (prepared according to Singh, J; Kissick, T. P.; Mueller, R. H. Organic Preparations and Procedures International (1989), 21(4), 501-4.) was added dropwise. The reaction mixture was heated to reflux and stirred overnight. The solution was cooled to RT and the solvent concentrated. Purification was accomplished by column chromatography (hexanes:EtOAc) to afford ethyl 3-ethyl-1H-indole-2-carboxylate (0.625 g, 41%) as a yellow solid. 1H NMR (400 MHz, DMSO-d6): δ ppm 11.45 (s, 1H) 7.66 (d, 1H) 7.41 (d, 1H) 7.25 (t, 1H) 7.05 (t, 1H) 4.34 (q, 2H) 3.05 (q, 2H) 1.35 (t, 3H) 1.19 (t, 3H). MS: m/z 218.0 (M+1). a reflux condenser attached The reaction mixture was heated to reflux the solvent concentrated Purification