反应详情

A 300 cc Hastelloy C autoclave was charged with 17.8 g (0.1 mol) of 4-acetoxyacetophenone (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 (3x). 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-AAP 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 (3x)
7. dry with materialThe organic phase was dried over anhydrous magnesium sulfate
8. filtrationfiltered
9. customthe solvent was removed on a rotary evaporator