Acetic Anhydride → HCID 13298061, compound

Participants

Reaction Conditions

Reaction Steps

The reaction is performed under dry conditions. 40.5 g of either (RR, SS)- or (RS, SR)-1,2-diphenyl-1-[4-[2-(N,N-dimethylamino)ethoxy]phenyl]butane-1,4-diol and 150 ml of acetic acid anhydride are placed in a flask. The temperature is raised to 90° C., where it is kept until the primary OH-group is completely acetylated. [4-acetoxy-1,2-diphenyl-1-[4-[2-(N,N-dimethylamino)ethoxy]phenyl]butan-1-ol is obtained as intermediate; m.p. of the (RR, SS)-isomer pair is 97°-9° C⟧ While stirring the reaction mixture, 30 ml of acetyl chloride in 50 ml of acetic acid anhydride are added at 90° C. The stirring is continued at this temperature for 2 h. The solvent is evaporated. Then 1M sodium carbonate solution is added in excess, after which the product is extracted in toluene. The solution is dried over sodium sulfate, and the solvent is evaporated. The yield of the pure isomer mixture (Z:E 2:1) is quantitative. The m.p. of the (Z)-isomer is 67°-9° C. prepared from the corresponding (Z)-alcohol by refluxing in acetic acid.

Provenance & Evidence