1,4-Benzodioxan → 6,7-Dichloro-2,3-dihydro-1,4-benzodioxine

Participants

Reaction Steps

The 5',6'-dichloro-2',3'-ethylenedioxy-4'-nitroacetophenone can be prepared by chlorinating 1,4-benzodioxane to give 6,7-dichloro-1,4-benzodioxane and then acetylating. The chlorination can be carried out by treating the benzodioxane with chlorine gas in acetic acid at 0 to 20° C. and requires 1 to 8 hours. The acetylation can be effected by reacting the 6,7-dichloro-1,4-benzodioxane with acetyl chloride in the presence of a Lewis acid in a suitable solvent (e.g., 1,2-dichloroethane, carbon disulfide, nitrobeanzene, etc.) at 20 to 40° C. and requires 24 to 48 hours.

Provenance & Evidence