Hydrochloric Acid → HCID 136334700, compound

Participants

Reaction Steps

To the solution from Step 3.3 (10 mmol) was added 2.9 g of 32% hydrochloric acid solution. Then, in an ice bath, 0.7 g (10 mmol) of sodium nitrite dissolved in 5 mL of water was added dropwise over a period of 10 minutes without allowing the temperature to exceed 5° C. The mixture was allowed to agitate in the ice bath for an additional hour after which unreacted nitrite was decomposed by addition of sulfaminic acid. The resulting solution was then added to a solution of 1.45 g (10 mmol) of 2-naphthol in 15 mL of water, 15 mL of isopropanol and 3.4 g of 30% sodium hydroxide solution. The azo coupling took place spontaneously with formation of a thick, red slurry. The mixture was allowed to agitate for an additional hour after which it was suction-filtered. The resulting dye was dried at 40° C. under vacuum.

Provenance & Evidence