Water → tert-Butyl (2-(5-chloropicolinoyl)-6-methoxyphenyl)carbamate

関与物質

反応条件

反応手順

To a cold (−23° C.), stirred solution of tert-butyl 2-methoxyphenylcarbamate (548 mg, 2.454 mmol) in ether (6 mL) under N2 was added t-BuLi (3.2 mL, 5.44 mmol). After stirring for 2.5 h, the reaction mixture was cooled to −78° C. To the reaction mixture was added a solution of ethyl 5-chloropicolinate (564.5 mg, 3.04 mmol) in ether (12 mL) dropwise via cannula over 5 min. The reaction mixture was stirred for 60 min, and then warmed to room temperature. After 1.5 h, to the reaction mixture was added H2O with vigorous stirring. The reaction mixture was diluted with EtOAc, and the organic phase was separated, washed with sat NaCl then dried (Na2SO4), filtered and concentrated to yield the product Intermediate A-29A (511.5 mg, 57.4% yield)) as a yellow solid: 1H NMR (400 MHz, chloroform-d) δ ppm 8.55 (1 H, dd, J=2.3, 0.6 Hz), 8.08 (1 H, dd, J=8.4, 0.7 Hz), 7.80 (1 H, dd, J=8.4, 2.4Hz), 7.16-7.25 (2 H, m), 7.06 (1 H, dd, J=7.5, 2.2Hz), 6.90 (1 H, s), 3.92 (3 H, s), 1.28 (9 H, s).

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