5-Benzyl-2-(4-fluorophenyl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine → 2-(4-Fluorophenyl)-4,5,6,7-tetrahydropyrazolo[1,5-A]pyrazine

Participants

Reaction Steps

To a degassed solution of Intermediate 1E (17 g, 55.3 mmol) in methanol (170 mL) was added 10% palladium on carbon (2.94 g, 2.77 mmol) and stirred under H2 atmospheric pressure for 3 h. The reaction mixture was filtered through CELITE® pad, washed with methanol (500 mL) and concentrated. The residue was triturated with diethyl ether (2×100 mL) and the resulting solid was filtered, rinsed with diethyl ether (200 mL) and dried under vacuum to afford Intermediate 1F (9 g, 75%). MS(ES): m/z=218 [M+H]+; 1H NMR (300 MHz, DMSO-d6) δ ppm 7.73-7.87 (m, 2H), 7.13-7.28 (m, 2H), 6.43 (s, 1H), 4.02 (t, J=5.57 Hz, 2H), 3.94 (s, 2H), 3.16 (t, J=5.57 Hz, 2H).

Provenance & Evidence