Graebe-Ullman reaction

Graebe-Ullman reaction

[¦gre·bə ′u̇l·mən rē‚ak·shən]
(organic chemistry)
Production of fluorenone by boiling 2-benzoylbenzenediazonium salts in dilute acid solution.
Reaction of 2-aminodiphenylamines with nitrous acid to form a benzotriazole which on heating loses nitrogen to form a carbazole.