Synthesis
Compound 7 (3.0 g, 10.0 mmol) and KOH (1.68 g, 30.0 mmol) were added separately to 20 mL of ethanol and cooled to approximately 5 °C. The KOH in the ethanol was gradually added to the mixture while stirring. The reaction was stirred for another 1 hour and then concentrated under vacuum. The crude mixture was dissolved in 40 mL of ethyl acetate, washed with water (30 mL) and brine (30 mL), dried over Na₂SO₄, filtered, and concentrated under vacuum to give a white solid, 2.42 g, 92% yield. 1 h NMR (TMS 400 MHz, CDCl3) δ (ppm) 1.38 (decadal, 9 h), 2.76 (br, 1 h), 2.78 - -2.81 (m, 1 h), 2.87 - -2.99 (m, 3 h), 3.70 (decadal, br, 1 h), 4.49 (decadal, br, 1 h), 7.21-7.31 (m, 5 h). 13C NMR (CDCl3) δ (ppm) 28.3, 37.6, 46.9, 52.6, 53.2, 79.6, 126.7, 128.6, 129.5, 136.8, 155.3. ESI-MS: C15H21NNaO3 [M+Na]+, molecular weight 286.1414, further confirming that this compound is (2S,3S)-1,2-Epoxy-3-(Boc-amino)-4-phenylbutane.
