Sodium Hydroxide → 2,2-Dimethylchroman-6-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 5.8 g (28.4 mmol) of 2,2-dimethyl-6-acetylchroman (Compound 57), 75 ml of dioxane, 300 ml of 10% sodium hypochlorite solution and 50 ml of a 20% solution of NaOH in water was heated at 65° C. for 0.5 hour. The mixture was then treated with another 200 ml of 10% sodium hypochlorite solution and then heated at 65° C. for a further 65 hours. The mixture was cooled to room temperature and washed with ether. The aqueous layer was then treated with sodium metabisulphite solution until it was negative to the potassium iodide-starch test. The aqueous solution was then acidified to pH=4 with dilute H2SO4 and stored in the refrigerator for 48 hours. The solution was then diluted with water and extracted with ether. The ether layers were combined and washed with saturated NaCl solution and then dried (MgSO4). The solution was filtered and the solvent was removed in-vacuo to give the title compound as a white solid. PMR (CDCl3): & 1.36 (6H, s), 1.84 (2H, t, J~6.8 Hz), 6.81 (1H, d, J~8.4 Hz), 7.82-7.89 (2H, m). MS exact mass, m/e 206.0942 (calcd. for C12H14o3 206.0943).

Provenance & Evidence