1-Pyrrolidinecarboxylic acid, 2-oxo-, 1,1-dimethylethyl ester → tert-butyl N-[4-(3-methoxyphenyl)-4-oxobutyl]carbamate

Participants

Reaction Conditions

Reaction Steps

Add 3-methoxyphenylmagnesium bromide (1.0 M in tetrahydrofuran, 91.0 mL, 91.0 mmol) dropwise to 1-(tert-butoxycarbonyl)-2-pyrrolidinone (11.9 mL, 70.0 mmol) in tetrahydrofuran (230 mL) at −40° C. After stirring at −40° C. for one hour, warm to 0° C. for 2 h before quenching with 2 M hydrochloric acid (70 mL). Dilute with methylene chloride (250 mL), separate the layers, and extract the aqueous layer with methylene chloride (2×200 mL). Dry the combined organic layers over magnesium sulfate, filter, and concentrate under reduced pressure to obtain the title compound (23.20 g, >100%). MS (APCI+): 194 [C16H23NO4—C5H8O2+H]+; 1H NMR (300 MHz, CDCl3): δ 7.55-7.47 (m, 2H), 7.39-7.33 (m, 1H), 7.12-7.08 (m, 1H), 4.66 (bs, 1H), 3.85 (s, 3H), 3.29-3.18 (m, 2H), 3.01 (t, J=7.1 Hz, 2H), 1.93 (quintet, J=7.0 Hz, 2H), 1.42 (s, 9H).

Provenance & Evidence