HCID 14839563, compound → HCID 14839564, compound

Participants

Reaction Steps

In a second stage, this hypobromite solution is slowly added to a stirred solution, cooled to about 5° C., of 43 g of 2-acetyl-1,4-dimethoxy-5,5,8,8-tetramethyl-5,6,7,8-tetrahydro naphthalene, obtained in stage (b) above, in 500 cm3 of dioxane. The rate of introduction is such that the temperature does not exceed 15° C. The reaction mixture is then left to stand overnight, diluted with 300 cm3 of water, then, at a temperature lower than 20° C., the excess sodium hypobromite is destroyed by the slow addition of a 25% aqueous solution of sodium bisulfite. The expected acid is then precipitated by acidifying the mixture by the addition of 380 cm3 of 6N HCl. The precipitate is filtered, washed with water and dried under reduced pressure. 40.8 g of 1,4-dimethoxy-5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthalene carboxylic acid are obtained in the form of a white solid having a melting point of 187° C.

Provenance & Evidence