Trifluoroacetic acid → HCID 178464319, compound

Participants

Reaction Steps

A solution of 38 mg of 1,1-diethyl-3-{3-[5-fluoro-6-(2-piperidin-1-ylethoxy)-1H-benzimidazol-2-yl]-1-(tetrahydropyran-2-yl)-1H-pyrazol-4-yl}urea is solubilized in 2 mL of dichloromethane and then 500 μl of trifluoroacetic acid are added. The reaction medium is stirred at ambient temperature overnight. The solvent is evaporated off under vacuum in a rotary evaporator and the crude is reacted again in 500 μL of dichloromethane and 500 μL of trifluoroacetic acid at ambient temperature for one hour. After concentration of the solvent in a rotary evaporator, the reaction crude is purified by flash chromatography on a 4 g silica cartridge, eluent: 100/0 to 90/10 dichloromethane/-methanol. 20 mg of 1,1-diethyl-3-{3-[5-fluoro-6-(2-piperidin-1-ylethoxy)-1H-benzimidazol-2-yl]-1H-pyrazol-4-yl}urea trifluoroacetate are isolated in the form of a yellow solid. 1H NMR (400 MHz, DMSO-d6, δ in ppm), for this batch, we observe a 60%-40% resolution of tautomers with: 1.24 (m, 6H); from 1.32 to 1.93 (m, 6H); 3.06 (broad m, 2H); from 3.23 to 3.68 (broad m, 4H); 3.41 (m, 4H); 4.44 (broad m, 2H); 7.21 (d, J=8.0 Hz, 0.6H); 7.32 (d, J=11.0 Hz, 0.4H); 7.38 (d, J=8.0 Hz, 0.4H); 7.49 (d, J=11.0 Hz, 0.6H); 8.01 (s, 1H); 9.32 (broad m, 1H); 9.74 (s, 0.4H); 9.77 (s, 0.6H); 13.0 (s, 1.6H); 13.05 (s, 0.4H).

Provenance & Evidence