Diisopropylethylamine → 4-(4-fluoro-3-(4-(2-(pyrrolidin-1-yl)ethoxy)piperidine-1-carbonyl)benzyl)phthalazin-1(2H)-one

Participants

Reaction Steps

2-fluoro-5-((4-oxo-3,4-dihydrophthalazin-1-yl)methyl)benzoic acid (1) (0.20 g, 0.67 mmol) and HBTU (0.381 g, 1.01 mmol) were added to DMF (4 mL), to this was added N-ethyl-N-isopropylpropan-2-amine (0.179 mL, 1.01 mmol) and then 4-(2-(pyrrolidin-1-yl)ethoxy)piperidine (109) (0.133 g, 0.67 mmol). The reaction was stirred for 2 hours before being evaporated to dryness and purified by preparative HPLC (Waters XBridge Prep C18 OBD column, 5μ silica, 19 mm diameter, 100 mm length), using decreasingly polar mixtures of water (containing 1% NH3) and MeCN as eluents. Fractions containing the desired compound were evaporated to dryness to afford the desired material as a white solid (0.287 g, 89% yield); 1H NMR (400.132 MHz, CDCl3) δ 1.65-1.81 (6H, m), 1.87-1.96 (3H, m), 2.53-2.61 (3H, m), 2.65-2.72 (2H, m), 3.04-3.14 (1H, m), 3.38-3.57 (3H, m), 3.61 (2H, t), 3.97-4.06 (1H, m), 4.28 (2H, s), 7.01 (1H, t), 7.21-7.33 (2H, m), 7.68-7.80 (3H, m), 8.43-8.48 (1H, m), 9.85-9.95 (1H, m); m/z (LC-MS, ESI+), RT=1.88 (M+H 479.5).

Provenance & Evidence