Efficient synthesis of polyfunctionalized carbazoles and pyrrolo[3,4-c]carbazoles via domino Diels–Alder reaction

• Ren-Jie Fang,
• Chen Yan,
• Jing Sun,
• Ying Han and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2021, 17, 2425–2432, doi:10.3762/bjoc.17.159

• reaction and sequential aromatization process. Keywords: carbazole; chalcone; Diels–Alder reaction; maleimide; pyrrolo[3,4-c]carbazole; 3-vinylindole; Introduction Carbazole is one of the most well-known privileged nitrogen-containing heterocycles. The carbazole skeleton is widely occurring in natural

• 3-(indol-3-yl)-1,3-diphenylpropan-1-one gave the expected indole-substituted chalcone A, which comprises the desired 3-vinylindole scaffold as the reactive diene. In the meantime, the carbonyl group of the chalcone is protonated to give the activated dienophile in the presence of p-toluenesulfonic