反应详情

A 300 cc Hastelloy C autoclave was charged with 17.8 g (0.1 mol) of 4-acetoxy acetophenone (4-AAP), 0.25 g of manganese (II) acetate tetrahydrate, 1.0 g of acetaldehyde, 25 g of acetic anhydride, and 125 g of acetic acid. An oxygen/nitrogen mixture was sparged into the autoclave at 1000 cc/min such that 5% oxygen was maintained in the vent. A 10% acetaldehyde in acetic acid solution was fed at a rate of 3.0 cc/h. The reaction was run at 150° C. and 100 psig for 3 h. using a stirring speed of 1000 rpm whereupon the acetic acid and acetic anhydride were removed on a rotary evaporator to yield orange crystals. The crystals were dissolved in ca. 150 mL of ethyl acetate and the solution was extracted with 100 mL of water (3×). The organic phase was dried over anhydrous magnesium sulfate, filtered, and the solvent was removed on a rotary evaporator to yield 4-acetoxybenzoic acid (4-ABA) at a conversion of 92.7% based on 4-HAP and with 55.1% selectivity to 4-ABA.

1. customAn oxygen/nitrogen mixture was sparged into the autoclave at 1000 cc/min such that 5% oxygen
2. temperaturewas maintained in the vent
3. customwas run at 150° C.
4. customa stirring speed of 1000 rpm whereupon the acetic acid and acetic anhydride were removed on a rotary evaporator
5. customto yield orange crystals
6. extractionthe solution was extracted with 100 mL of water (3×)
7. dry with materialThe organic phase was dried over anhydrous magnesium sulfate
8. filtrationfiltered
9. customthe solvent was removed on a rotary evaporator