1,3-Dibromopropane → HCID 57637347, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-(1-tert-butoxycarbonyl-5-phenyl-1H-thieno[3,2-c]pyrazol-3-yl)-6-hydroxy-indole-1-carboxylic acid tert-butyl ester [950 mg, 1.79 mmol, Intermediate (49)], cesium carbonate (1.75 g, 5.37 mmol), and 1,3-dibromopropane (6.0 mL) was heated at 90° C. under nitrogen. After 1.5 hours, the mixture was cooled to ambient temperature, filtered, and the insolubles washed twice with dichloromethane (10 mL). The filtrate was concentrated in vacuo to yield a cloudy oil. The crude product was chromatographed on silica, eluting first with 80% dichloromethane/heptane and then 100% dichloromethane to give 6-(3-bromo-propoxy)-2-(1-tert-butoxycarbonyl-5-phenyl-1H-thieno[3,2-c]pyrazol-3-yl)-indole-1-carboxylic acid tert-butyl ester [760 mg, 65%, intermediate 50] as a white foam. TLC Rf 0.37 (silica, dichloromethane); LC/MS: 674 (M+Na), RT=2.60 minutes.

Provenance & Evidence