1,3-Dibromopropane → HCID 59224762, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-[1-tert-butoxycarbonyl-5-(3-methoxy-phenyl)-1H-thieno[3,2-c]pyrazol-3-yl]-6-hydroxy-indole-1-carboxylic acid tert-butyl ester [1.19 g, 2.12 mmol, Intermediate (57)], cesium carbonate (2.07 g, 6.35 mmol), and 1,3-dibromopropane (8.0 mL) was heated at 75° C. under nitrogen. After 6 hours, the mixture was cooled to ambient temperature and let stand overnight. The mixture was filtered, and the insolubles washed twice with dichloromethane (10 mL). The filtrate was concentrated in vacuo to yield a golden oil. The crude product was chromatographed on silica, eluting with a gradient of 30% ethyl acetate/heptane to 50% ethyl acetate/heptane to give 6-(3-bromo-propoxy)-2-[1-tert-butoxycarbonyl-5-(3-methoxy-phenyl)-1H-thieno[3,2-c]pyrazol-3-yl]-indole-1-carboxylic acid tert-butyl ester [1.11 g, 76%, Intermediate (58)] as a white foam. TLC Rf 0.46 (silica, 40% ethyl acetate/heptane); LC/MS: 682.2 (M+H), RT=3.23 minutes.

Provenance & Evidence