p-Toluenesulfonic acid → HCID 19599434, compound

Participants

Reaction Steps

A stirred solution of methyl 2-aminoindole-3-carboxylate (I. Forbes et al, J. Chem. Soc. Perkin 1, 1992, 275) (0.25 g, 0.0013 mole) in xylene (5 ml) was treated with 2,4-pentanedione (0.13 g, 0.0013 mole) and a few crystals of 4-toluenesulphonic acid and heated under reflux for 2 h. The mixture was concentrated in vacuo and the residue dissolved in chloroform (20 ml), washed with water (2×20 ml), dried (MgSO4) and concentrated in vacuo to afford the title compound as a brown solid (0.25 g, 75%).

Provenance & Evidence