Studies towards the synthesis of the marine alkaloid chartelline C

2,6-Dibromoindole 5 underwent regioselective Sonogashira coupling at the 2 position with simple acetylenic partners. While, imidazole-acetylene 16 failed to couple to 5, cyclic carbonate 19 succeeded to give 20, which was further elaborated into indole-imidazole 23.