Sodium Carbonate → 6-(2,6-Difluorophenyl)-5-(4-formylphenyl)-pyrazolo[1,5-a]pyrimidine-3-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

2.3 g (7.1 mmol) 5-Chloro-6-(2,6-difluorophenyl)pyrazolo[1,5-a]pyrimidine-3-carboxylic acid methyl ester are given in 24 mL dimethoxyethane. 13.9 mL Na2CO3 solution (10%) and 1.18 g (7.8 mmol) 4-formylboronic acid are added. After addition of 0.26 g (0.32 mmol) 1,1′-bis(diphenylphosphino)ferrocenedichloropalladium(II) the reaction mixture is purged 3× with argon and heated at 90° C. for 2 hours. The reaction mixture is cooled down, treated with water and extracted 3 times with dichloromethane. The organic phase is washed with brine and dried (Na2SO4). The solvent is removed and the crude product purified via chromatography (silicagel, dichloromethane/methanol). 2.57 g (64.4%) of the slightly contaminated compound are obtained.

Provenance & Evidence