Boron Trichloride → HCID 178516588, compound

Participants

Reaction Steps

Boron trichloride (1M solution in dichloromethane; 8 ml, 8 mmol) was added dropwise to a solution of 4-[3-(2,4-Bis-benzyloxy-5-chloro-phenyl)-1H-pyrazol-4-yl]-piperazine-1-carboxylic acid tert-butyl ester (1.5 g, 2.6 mmol) in dichloromethane (15 ml) at 0° C. The resulting mixture was stirred at room temperature for 1 h, then basified with saturated sodium bicarbonate solution. The suspension was concentrated in vacuo, azeotroping with toluene until the residue was dry. The residue was triturated with dichloromethane:ethanol (1:1; 15 ml) and filtered. The filtrate was purified on a bond elute cartridge (20 g) eluting with dichloromethane:ethanol:ammonia, 50:8:1 then 20:8:1 to give 4-chloro-6-(4-piperazin-1-yl-1H-pyrazol-3-yl)-benzene-1,3-diol as a pale yellow solid (400 mg) (Example 2)

Provenance & Evidence