Silver(I)-catalysed domino alkyne-annulation/Diels–Alder reaction: a mild synthetic approach to tetrahydrospiro[carbazole-4,3′-indoline] scaffolds

A mild and efficient AgOTf catalyzed alkyne-annulation/Diels–Alder cascade for the construction of tetrahydrospiro[carbazole-4,3′-indoline] derivatives has been established from N-tosyl-2-(but-3-en-1-yn-1-yl) aniline in the presence of methyleneindolinones. This strategy provides access to the one-pot synthesis of a new class of various novel and structurally complex spirooxindole molecules with high diastereoselectivity.