Potassium Carbonate → (1R,2R)-4-(tert-Butyl-dimethyl-silanyloxy)-cyclopentane-1,2-dicarboxylic acid monoethyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of (1R,2R)-4-(tert-Butyl-dimethyl-silanyloxy)-cyclopentane-1,2-dicarboxylic acid 1-ethyl ester 2-(tert-Butyl-dimethyl-silanyl) Ester (epimeric mixture, 12.09 g) in ethanol (340 mL) and tetrahydrofuran (114 mL) was slowly added a solution of potassium carbonate (16.68 g) in water (114 mL). After 45 min at room temperature, the solvents were removed in vacuo. Brine was added to the residue and the mixture was cooled to 0° C. then the pH was adjusted to 4-5 using a 10% aqueous solution of potassium hydrogenosulfate. The resulting mixture was extracted with diethylether. The combined organic layers were washed with brine then dried over sodium sulfate and concentrated in vacuo to afford the title compound (8.03 g, 90%) as light yellow oil, used in the next step without further purification. MS (EI): 315.2 (M−H)−.

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