Hydrochloric Acid → 2,7-Diamino-9-fluorenone

Participants

Reaction Steps

2,7-Dinitro-9-fluorenone (162 g, 0.6 mol, from Aldrich) was added cautiously to a solution of hydrated stannous chloride (1100 g, 4.9 mol, from Aldrich) in a mixture of concentrated hydrochloric acid (900 ml) and acetic acid (1600 ml). The suspension was stirred and refluxed for 1 hour. The mixture was cooled to room temperature, and a solid appeared. The solid was harvested by filtration. The solid was washed first with concentrated hydrochloric acid, and then with water until the filtrate color was violet. The residue was dissolved in boiling water. The solution was filtered and then made alkaline with sodium hydroxide to from a precipitate. The precipitate was washed with water, dried, and recrystallized from dioxane. The yield of 2,7-diamino-9-fluorenone was 108 g (85.7%). The melting point was found to be 284–286° C.

Provenance & Evidence