Trifluoroacetic acid → 3-[4-(1-Amino-cyclobutyl)-phenyl]-2-phenyl-7H-pyrano[2,3-e]indazol-4-one

Participants

Reaction Steps

To a solution of (1-{-4-[4-oxo-2-phenyl-7-(2-trimethylsilanyl-ethoxymethyl)-4,7-dihydro-pyrano[2,3-e]indazol-3-yl]-phenyl}-cyclobutyl)-carbamic acid tert-butyl ester (67 mg, 0.13 mmol) in DCM (2.0 mL), was added TFA (500 μL, 6.7 mmol). The reaction mixture was stirred at RT for 1 hour. The solution was diluted with methanol (10 mL) and loaded onto an SCX-2 cartridge. The cartridge was washed repeatedly with methanol before elution with 2 M ammonia in methanol. The eluent was collected and concentrated in vacuo. The resulting residue was subjected to flash chromatography (SiO2, gradient 7-10% methanol in DCM) to give the title compound as a light pink solid (25 mg, 47%). 1H NMR (400 MHz, DMSO-d6): δ 8.54 (d, J=1 Hz, 1H), 8.00 (d, J=9 Hz, 1H), 7.63 (dd, J=1 and 9 Hz, 1H), 7.52-7.49 (m, 2H), 7.44-7.34 (m, 5H), 7.17-7.14 (m, 2H), 2.41-2.33 (m, 2H), 2.11-2.03 (m, 2H), 2.03-1.92 (m, 1H), 1.70-1.60 (m, 1H). LCMS (Method E): RT=3.09 min, [M+H]+=407.

Provenance & Evidence