5-Chloro-2-methoxybenzenebutanoic acid → 34910-81-1

Participants

Reaction Steps

A flask containing 1600 g. of polyphosphoric acid and 160 g. (0.70 mole) 4-(5-chloro-2-methoxyphenyl)butyric acid was heated on a steam bath (internal temperature 90°-95° C.) for 1.5 hours. The hot reaction mixture was then poured onto 2 liters of crushed ice with stirring. The quenched mixture was stirred for 30 minutes, then extracted 3 times with 500 ml. portions of chloroform, the extract carbon treated, dried with MgSO4 and filtered. The filtrate was concentrated in vacuo to afford 146 g. of dark oil. This was dissolved in ether, washed with aqueous NaHCO3, then water, carbon treated, dried over MgSO4 and evaporated to dryness. The oil thus produced was distilled under high vacuum to obtain 65.4 g. of product (44% yield). Upon cooling the distillate it crystallized, m.p. 46°-48° C.

Provenance & Evidence