Trifluoroacetic acid → HCID 131724941, compound

Participants

Reaction Steps

Trifluoroacetic acid (3 ml) was added to a stirred solution of 1,1-dimethylethyl 4-hydroxy-4-[5-({[3-(5-methylisoxazol-3-yl){1,2,4]triazolo[3,4-α]phthalazin-6-yl]oxy}methyl)pyridin-2-yl]-1-piperidine carboxylate(707 mg, 1.27 mmol) in CH2Cl2 (30 ml) at room temperature and the reaction stirred for 6 h. The reaction mixture was concentrated under reduced pressure, 2N NaOH solution (30 ml) was added and the resulting precipitate was filtered off. After dissolving in MeOH/CH2Cl2 (60 ml) and dry loading onto alumina, the crude residue was purified by column chromatography on alumina using 5-7% MeOH/CH2Cl2 containing 1% NH3 to yield the desired phthalazine (361 mg, 62%). 1H NMR (360 MHz, d6-DMSO) δ 8.80 (1H, s), 8.55 (1H, d, J=7.1 Hz), 8.23 (1H, d, J=7.1 Hz), 8.15-8.03 (2H, m), 7.93 (1H, t, J=7.1 Hz), 7.71 (1H, d, J=7.4 Hz), 7.07 (1H, s), 5.67 (2H, s), 5.06 (2H, s), 2.91 (2H, t, J=11.2 Hz), 2.74 (2H, d, J=11.2 Hz), 2.60 (3H, s), 2.04 (2H, td, J=12.4, 4.0 Hz), 1.44 (2H, d, J=12.4 Hz). m/z (ES+) 458 (M+H+).

Provenance & Evidence