1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → Ethyl 3-[7-(5-{3-cyano-4-[(1-methylethyl)oxy]phenyl}-1,2,4-oxadiazol-3-yl)-6-fluoro-1H-indol-3-yl]propanoate

Participants

Reaction Steps

HOBT (672 mg) and EDCI (841 mg) were added to a solution of 3-cyano-4-[(1-methylethyl)oxy]benzoic acid (450 mg) in THF (10 mL). The resulting solution was stirred for 1 hour. Ethyl 3-{6-fluoro-7-[(Z)-(hydroxyamino)(imino)methyl]-1H-indol-3-yl}propanoate (D145) (836 mg) in THF (5 mL) was added, and the reaction mixture was stirred at RT for 2 hours. TBAF (2.02 g) was then added. The reaction vessel was sealed and heated in Biotage Initiator using initial normal to 120° C. for 2 hours. After cooling, the reaction was quenched with water, and extracted with EtOAc for 3 times. The combined organic solution was washed with brine, and dried over anhydrous sodium sulfate. The dried solution was concentrated. The residue was purified by column chromatography to afford ethyl 3-[7-(5-{3-cyano-4-[(1-methylethyl)oxy]phenyl}-1,2,4-oxadiazol-3-yl)-6-fluoro-1H-indol-3-yl]propanoate (D148) (875 mg) as a yellow solid. MS (ES): C25H23FN4O4 requires 462; found 463.2 (M+H+).

Provenance & Evidence