Methanamine, N-methoxy-, hydrochloride (1:1) → (RS)-[2-(4-Benzyloxy-phenyl)-1-(methoxy-methyl-carbamoyl)-ethyl]-carbamic acid tert-butyl ester

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Reaction Steps

DIPEA (28.2 ml, 20.9 g, 162 mmol) was added to a stirred solution of (RS)-3-(4-benzyloxy-phenyl)-2-tert-butoxycarbonylamino-propionic acid (20.0 g, 53.9 mmol), BOP (25.00 g, 56.5 mmol) and MeONHMe.HCl (5.52 g, 56.6 mmol) in DMF (300 mL). After stirring 2 hr, the DMF was evaporated and the residue was dissolved in EtOAc and washed with water, 5% aq. HCl, saturated aq. NaHCO3 and brine, then dried with Na2SO4 and evaporated to afford (RS)-[2-(4-Benzyloxy-phenyl)-1-(methoxy-methyl-carbamoyl)-ethyl]-carbamic acid tert-butyl ester (22.39 g, 100%), mp 107.1-108.7° C. 1H NMR (CDCl3) δ 0.40 (s, 9H), 2.83 (dd, J=6.2, 14.2 Hz, 1H), 3.00 (dd, J=6.1, 13.6 Hz, 1H), 3.17 (s, 3H), 3.65 (s, 3H), 4.91 (br s, 1H), 5.04 (s, 2H), 5.15 (br d, J=7.1 Hz, 1H), 6.90 (d, J=8.6 Hz, 2H), 7.09 (d, J=8.5 Hz, 2H), 7.32-7.44 (m, 5H). 13C NMR (CDCl3) δ 172.3, 157.7, 155.2, 137.1, 130.4, 128.9, 128.5, 127.9, 127.4, 114.7, 79.6, 70.0, 61.5, 51.6, 38.0, 32.1, 28.3.

Provenance & Evidence