Isopropanol → HCID 22145851, compound

Participants

Reaction Conditions

Reaction Steps

Solid potassium permanganate (5.87 g) is added portionwise during 30 minutes to a suspension of 4-cyclopentyloxy-2-hydroxymethyl-5-methoxypyridine (4.0 g) in water (100 mL) at 50±5° C. When the addition is complete the mixture is heated at 70±5° C. for 45 min and then cooled to room temperature. A solution of potassium hydroxide (1.95 g) in water (50 mL) is added followed by sufficient isopropanol to react with excess potassium permanganate. After stirring for 10 minutes the mixture is filtered through diatomaceous earth and the filtrate concentrated to ˜70 mL. The solution is acidified to pH 2 with concentrated aqueous hydrochloric acid and extracted with chloroform. After drying (MgSO4) the extracts are evaporated to give 4-cyclopentyloxy-5-methoxypyridine-2-carboxylic acid (2.5 g) as a white solid, m.p. 184-5° C. [1Hnmr in D6-DMSO shifts relative to Me4Si: 1.55-1.79, 6H, m; 1.95, 2H, m; 3.92, 3H, s; 5.00, 1H, m; 7.59, 1H, s; 8.24, 1H, s.].

Provenance & Evidence