Hydrochloric Acid → Procromil

Participants

Reaction Steps

To a refluxing solution of 4-oxo-10-(2-oxopropyl)-6,7,8,9-tetrahydro-4H-naphtho[2,3-b]pyran-2-carboxylic acid (3.1 g) in water (100 ml) containing sodium hydroxide (0.12 g) was added portion-wise sodium borohydride (3.04 g). The resulting mixture was heated under reflux for 2 hours. After cooling the solution was acidified with concentrated hydrochloric acid and the precipitate filtered off, washed with water and dried giving the title compound as a white solid, mp 235°.

Provenance & Evidence