Chiang Mai Journal of Science

 The one-pot three-components synthesis of 3-(α-arylaminobenzyl)indoles is achieved from indole, aromatic aldehydes and anilines by  using L-proline as a catalyst. The reaction produced 3-alkyl-indoles in dominance over the bisindolyl alkanes. The reported L-proline catalyzed synthetic methodology is an environmentally benign alternative for the synthesis of 3-alkyl-indoles with comparable catalytic efficiency to that of costly and toxic metal based catalysts.