Reaction #5930

Reaction equation

chloroacetyl chloride

1-amino-2-naphthol

N,N-dimethylaniline

tetrahydrofuran

→

1H-naphtho[2,1-b][1,4]oxazin-2(3H)-one

Solvents

ethyl acetate

Conditions

Workup

1. 1
   Washthe ethyl acetate layer is washed
2. 2
   Otherdried
3. 3
   workup.DISTILLATIONdistilled
4. 4
   Otherto remove the solvent
5. 5
   workup.DISSOLUTIONThe resulting oil is dissolved in acetone (500 ml)
6. 6
   workup.ADDITIONis added potassium carbonate (75 g)
7. 7
   Temperaturethe mixture is refluxed for 2 hours
8. 8
   workup.DISTILLATIONacetone is distilled off
9. 9
   workup.ADDITIONTo the residue is added water
10. 10
    Otherthe precipitate is separated by filtration
11. 11
    Washwashed
12. 12
    Otherdried
13. 13
    Otherrecrystallized from tetrahyrofuran

Procedure

To a mixture of 1-amino-2-naphthol (16.9 g), N,N-dimethylaniline (19.3 g) and tetrahydrofuran (200 ml) is added dropwise chloroacetyl chloride under ice cooling, and the mixture is stirred at the same temperature for one hour. To the reaction mixture is added ethyl acetate, and the ethyl acetate layer is washed, dried and distilled to remove the solvent. The resulting oil is dissolved in acetone (500 ml) and thereto is added potassium carbonate (75 g), and the mixture is refluxed for 2 hours, and acetone is distilled off. To the residue is added water, and the precipitate is separated by filtration, washed, dried and recrystallized from tetrahyrofuran to give 1H-naphtho[2,1-b][1,4]oxazin-2(3H)-one (13.1 g). M.p. 219°-220.5° C.

Source