1,2-Azetidinedicarboxylic Acid 1-(1,1-Dimethylethyl) Ester, is an useful intermediate in the synthesis of pharmaceutical compounds including inhibitors and receptor Antagonists. It can be used in the synthesis of polypeptides.
To a mixed solution of (R)-azetidine-2-carboxylic acid (20 g, 200 mmol), water (200 mL) and dioxane (200 mL) was slowly added dropwise a solution of di-tert-butyl dicarbonate (Boc2O) in dioxane (100 mL) at 0 °C. After the dropwise addition was completed, the reaction mixture was stirred at room temperature for 1 hour. After the reaction was complete, the mixture was concentrated and ether (200 mL) and water (200 mL) were added to the residue. The aqueous layer was acidified to pH 3-4 with 2N hydrochloric acid and then extracted with ethyl acetate (200 mL). The organic layers were combined, dried over anhydrous sodium sulfate and concentrated to give (R)-N-BOC-azetidine-2-carboxylic acid (40 g) in quantitative yield.LRMS (M-100 + H*) m/z 102.1.
[1] Patent: WO2008/16643, 2008, A2. Location in patent: Page/Page column 257
[2] Journal of Medicinal Chemistry, 1998, vol. 41, # 4, p. 407 - 412
[3] Patent: US6133253, 2000, A
