Reaction #56518

Reaction equation

9-hydroxy-1-oxo-1H-naphtho[2,1-b]pyran-2-carboxaldehyde acetate

hydroxylamine hydrochloride

sodium formate

→

9-Hydroxy-1-oxo-1H-naphtho[2,1-b]pyran-2-carbonitrile

Solvents

formic acid

Conditions

Workup

1. 1
   Temperatureis refluxed for 30 hrs
2. 2
   OtherThe product crystallize
3. 3
   Temperatureon cooling
4. 4
   Filtrationis filtered
5. 5
   Washwashed with acetone

Procedure

A mixture of 9-hydroxy-1-oxo-1H-naphtho[2,1-b]pyran-2-carboxaldehyde acetate (1 mm), hydroxylamine hydrochloride (1.3 mm) and sodium formate (2 mm) is refluxed for 30 hrs. in formic acid (3 parts). The product crystallize on cooling, is filtered and washed with acetone. The dry crystals are light beige, m.p. 289°-92° C.

Source