Sodium Iodide → 2,2-Dimethylpropionic acid 2-((R)-3-tert-butoxycarbonylaminopiperidin-1-yl)ethyl ester

Beteiligte Stoffe

Reaktionsschritte

A mixture of 2,2-dimethylpropionic acid 2-bromoethyl ester (2.3 g, 11 mmol), (R)-piperidin-3-ylcarbamic acid tert-butyl ester (2 g, 10.0 mmol), potassium carbonate (4.15 g, 30 mmol) and sodium iodide (0.15 g, 1 mmol) in DMF (20 mL) was stirred at RT for 2 days. The reaction mixture was partitioned between water and EtOAc. The aqueous phase was extracted with EtOAc and the combined organic fractions washed with water, followed by brine, then dried (Na2SO4) and concentrated in vacuo. The resulting residue was purified by column chromatography (Si—PCC, eluant 10-40% EtOAc in cyclohexane) affording the title compound as a colourless oil (2.884 g, 88%). 1H NMR (CDCl3, 300 MHz): 5.09 (1H, bs), 4.25-4.07 (2H, m), 3.73 (1H, bs), 2.63-2.52 (3H, m), 2.49 (1H, bs), 2.31-2.24 (1H, m), 1.74-1.61 (1H, m), 1.59-1.49 (3H, m), 1.44 (9H, s), 1.21 (9H, s).

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