Pyridine → (+/-)-(6-Acetoxy-2,5,7,8-tetramethylchroman-2-yl)acetic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 66.1 g. (0.25 mol.) of (±)-(6-hydroxy-2,5, 7,8-tetramethylchroman-2-yl) acetic acid and 250 ml. each of pyridine and acetic anhydride was stirred at 25° C. under N 2 for 20 hours and stripped of solvent at 40° C. to give an orangebrown oil. To a suspension of this material in 500 ml. of H 2 O and 100 ml. of tetrahydrofuran was added 166 g. (2.0 mol.) of NaHCO 3. the suspension was stirred at 25° C. for 4.0 hours, washed with ether, acidified with 2N-aqueous HCl and extracted with ether. The ether solutions were washed with saturated brine, dried over sodium sulfate and stripped of solvent to give (±)-(6-acetoxy-2,5,7,8-tetramethylchroman-2-yl) acetic acid as and orangeish resin. Crystallization from diethyl ether petroleum ether (b.p. 30°-60° C.) gave (±)-(6-acetoxy-2,5,7,8 -tetramethylchroman-2-yl) acetic acid as a granular white solid.

Provenance & Evidence