1,4-Dioxane → 3,4,5,6-Tetrahydro-6-methylazepino[4,3-b]indol-1(2H)-one

Participants

Reaction Steps

1,2,3,9-Tetrahydro-9-methyl-4H-carbazol-4-one oxime (24 g) and polyphosphoric acid (600 g) in dioxan (500 ml) were treated according to the method described for Intermediate 6. The solid (22 g) obtained by evaporation of the organic extracts was recrystallised from ethyl acetate (300 ml) to give a solid (19.2 g). This was purified by FCC eluting with System A (200:8:1) to give the title compound (5.5 g), m.p. 212°-215°.

Provenance & Evidence