Sodium Hydroxide → Oxane-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Add 40% w/w sodium hydroxide in water (264.5 mL, 1.15 eq) to a solution of methyl tetrahydro-2H-pyran-4-carboxylate (500 g, 3.47 mol) in methanol (2.26 L). Stir at 50° C. for seven hours. Evaporate solvent, dissolve residue in water (2 L) and wash with methyl-tert-butyl ether (2×1.2 L). Add aqueous 35% hydrochloric acid to the aqueous layer (adjusting pH to 4) and extract with methyl tert-butyl ether (2×1.2 L). Dry over anhydrous magnesium sulfate and concentrate in vacuo. As material still contains water, dissolve the solid in dichloromethane and discard the aqueous layer. Dry the organics with anhydrous sodium sulfate and concentrate in vacuo to give tetrahydro-2H-pyran-4-carboxylic acid (312.76 g, 69%). 1H NMR (300 MHz, DMSO-d6) δ 11.21 (br s, 1H), 3.97 (m, 2H), 3.44 (m, 2H), 2.56 (m, 1H), 1.81 (m, 4H).

Provenance & Evidence