反应详情

To a freshly-prepared solution of (±)-4-{3-[3-[2-(1-hydroxycyclohexyl)ethyl]-4-oxo-2-thiazolidinyl]propyl}benzoic acid (1) (10 g, 25.6 mmol) in dry N,N-dimethylformamide (86 ml) contained in a 250 ml round bottom flask is added finely-ground potassium carbonate (3.54 g, 25.6 mmol) followed by methyl iodide (1.6 ml, 25.6 mmol). The resulting suspension is protected from atmospheric moisture with a magnesium sulfate drying tube and is stirred at room temperature for 19.5 hours. The reaction mixture is poured into water (175 ml) contained in a separatory funnel and then is extracted with ether (3×40 ml). The organic extracts are combined, washed with saturated aqueous sodium bicarbonate (3×30 ml), dried over sodium sulfate and filtered. Evaporation (in vacuo) of the filtrate leaves the desired ester 2 as a pale yellow oil (10.55 g): tlc, Rf =0.4 (homogeneous, UV detection) on silica gel with ethyl acetate:hexane (7:3; v:v) as eluent; ir (2% solution in chloroform) 3400 (w), 1710 (s), 1600 (s) and 1280 (s) cm-1.

1. customThe resulting suspension is protected from atmospheric moisture with a magnesium sulfate drying tube
2. customcontained in a separatory funnel
3. extractionis extracted with ether (3×40 ml)
4. washwashed with saturated aqueous sodium bicarbonate (3×30 ml)
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. customEvaporation (in vacuo) of the filtrate