反应详情

A mixture of 1,2-naphthoquinone (commercially available, 2.0 g) and 2,3-diamino-benzoic acid, diacetate salt, (3.79 g) was heated to reflux in acetic acid (30 mL) for 2 hours. The reaction mixture was cooled and the solvent removed in vacuo to yield a gum. This was purified using flash chromatography to yield a 2:1 mixture of the desired title compound to the undesired benzo[a]phenazine-8-carboxylic acid (840 mg). The two isomers were separated after further modification (see Reference Example 3B below).

1. temperaturewas heated
2. temperatureThe reaction mixture was cooled
3. customthe solvent removed in vacuo
4. customto yield a gum
5. customThis was purified
6. customto yield