Acetic Anhydride → HCID 59289849, compound

Participants

Reaction Conditions

Reaction Steps

40 g (0.153 mol) of 2-hydroxy-2-(4-methoxy-benzoyl)-cyclohexanecarboxylic acid (=compound of example 6) are dissolved in 125 ml of acetic anhydride. 24.37 g (0.153 mol) of bromine in 24 ml of acetic acid are added slowly to this solution over 1 hour 40 minutes while keeping the temperature at 20° C. After addition of ⅓-½ equivalent of the bromine solution, a yellowish suspension is formed. The reaction mixture is stirred for 30 minutes at 20° C., followed by 1 hour at 0° C. in order to achieve complete precipitation of the product. The yellowish solid is filtered and washed with acetic acid anhydride to give 51 g (88%) 7a-bromo-1-(4-methoxy-phenyl)-3-oxo-octahydro-isobenzo-furan-1-yl acetate as a yellowish-white solid that is dried in vacuum at 40° C. and used for the next step without further purification.

Provenance & Evidence