Hydrochloric Acid → 3-(4-Methoxyphenoxy)propionic acid

Participants

Reaction Conditions

Reaction Steps

A 945 g (5.34 mol, 1 eq.) sample of 1 (3-(4-methoxyphenoxy)propionitrile (1)) was charged to a 22 L round bottom flask equipped with an overhead stirrer under N2. To the stirred solids, 4 L of concentrated HCl was slowly added, followed by 2 L of H2O. The reaction mixture was heated to 100° C. for 3.5 h, at which point the reaction was complete by HPLC analysis. The reaction was cooled to 10° C. by the addition of ice to the reaction mixture, and was filtered. The dried solids gave 920 g of crude 2. The crude material was dissolved in 5 L of 6 wt. % sodium carbonate (such that pH=9), and 2 L of DCM (dichloromethane) was added to the reaction vessel. After stirring thoroughly, the organic layer was separated and discarded via a separatory funnel, and the aqueous layer charged back into the 22 L flask. The pH of the aqueous layer was carefully adjusted to 4.0, by slow addition of 6 M HCl. The precipitated solids were filtered, and dried in a vacuum oven to give 900 g of 2 as a white solid (Yield: 86.04%). 1H NMR (450 MHz, CDCl3); δ=2.78 (t, 2H; CH2COOH); 3.70 (s, 3H; OCH3); 4.18 (t, 2H; OCH2); 6.78 (m, 4H; Ar—H); 13C NMR (112.5 MHz, CDCl3): δ=34.703 (CH2COOH); 55.925 (OCH3); 64.088 (OCH2); 114.855 (CH3OCCH); 115.984 (CH2OCCH); 152.723 (CH3OC); 154.302 (CH2OC); 177.386 (COOH).

Provenance & Evidence