Cesium carbonate → Ethyl 3-((1-(2-(tert-butoxy)-2-oxoethyl)-6-chloro-7-fluoro-2-methyl-1H-indol-3-yl) thio)-2-fluorobenzoate

Participants

Reaction Steps

To a stirred solution of compound 4 (140 mg, 0.36 mmol) in DMF (3 mL) under inert atmosphere were added tert-butyl 2-bromoacetate (0.08 mL, 0.54 mmol), Cs2CO3 (238 mg, 0.73 mmol), Bu4NBr (5.9 mg, 0.018 mmol) at RT and stirred for 1 h. The reaction was monitored by TLC; after completion of the reaction, the reaction mixture was diluted with water (20 mL) and extracted with EtOAc (2×20 mL). The combined organic extracts were washed with water (15 mL) dried over Na2SO4, filtered and concentrated under reduced pressure to obtain the crude compound 5 (200 mg) as a pale green semisolid. 1H NMR (500 MHz, CDCl3): δ 7.61 (t, J=7.0 Hz, 1H), 7.21 (d, J=8.0 Hz, 1H), 7.09 (t, J=8.5 Hz, 1H), 6.90 (t, J=8.5 Hz, 1H), 6.74 (t, J=6.5 Hz, 1H), 4.95 (s, 2H), 4.40 (q, 2H), 2.44 (s, 3H), 1.52 (s, 9H), 1.42 (t, J=7.5 Hz, 3H); LC-MS: 96.7%; 513.6 (M+H2O); (column: X Select CSH C-18, 50×3.0 mm, 3.5 μm); RT 4.72 min. 5 mM NH4OAc: ACN; 0.8 mL/min).

Provenance & Evidence