4-Bromobenzoylacetonitrile

4-Bromobenzoylacetonitrile is a useful research chemical used in the preparation of mechanistic studies, and fluorescence of naphtho[1,8-bc]pyrans via rhodium-catalyzed cascade oxidative annulation of benzoylacetonitriles with internal alkynes.

4-Bromobenzoylacetonitrile can be prepared from 3-bromobenzoic acid as a reaction material, the intermediate 3-bromobenzoic acid methyl ester is prepared first, and 4-bromobenzoylacetonitrile is generated under the action of sodium cyanide.

 

The nitrile is purified by dissolving in slightly alkaline H2O (charcoal), filtering and acidifying with HCl to give colourless needles (m 162-163o). It recrystallises from EtOH. With Me2SO4/KOH at 130o it gives 4-bromo-methoxycinnamylnitrile m 58.5-59.5o (from high boiling pet ether) [Fuson & Wolf J Am Chem Soc 61 1940 1939, Grathaus & Dains J Am Chem Soc 58 1334 1936]. [Beilstein 10 III 2998.]