Sulfuric Acid → Indolo(3,2-b)carbazole

Participants

Reaction Steps

Under a nitrogen gas stream, about 250.69 g (i.e., about 205.8 mmol) of 3,3′-methylenediindole and about 30.55 g (i.e., about 206.1 mmol) of triethyl orthofomate are dissolved and mixed in methanol within a 3-neck flask. Thereafter, about 5.0 g (i.e., 51.5 mmol) of enriched sulfuric acid is slowly added little by little into the 3-neck flask and then the mixture within the 3-neck flask is refluxed during a single hour. The mixture within the 3-neck flask is frozen to be a normal temperature. Subsequently, about 33 g of indolo(3,2-b)carbazole corresponding to a compound of dark brown is obtained by filtering the frozen mixture.

Provenance & Evidence