1,4-Dibromobutane → 5-(4-Bromo-butoxy)-indole-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

6.07 g (26 mmol) 5-Hydroxy-indole-1-carboxylic acid tert-butyl ester in 10 ml acetone were treated with 13.8 g (100 mmol) powdered K2CO3 and 11.8 ml (100 mmol) 1,4-dibromobutane. The suspension was stirred at 100° C. for 3 h, cooled to RT, and acetone was added. The suspension was filtered and concentrated. The residue was redissolved in ether and 0.5 M HCl, the inorganic phase was extracted with ether and the combined organic phases were washed with water, and dried over Na2SO4. Column chromatography on silica gel with a gradient hexane to hexane/EtOAc 19:1 yielded 7.2 g (65%, 3 steps) 5-(4-Bromo-butoxy)-indole-1-carboxylic acid tert-butyl ester as colorless oil, MS: 367 (M, 1Br).

Provenance & Evidence