Reaction Steps
To a solution of NEt(iPr)2 (150 μL, 111 mg, 0.861 mmol), DMAP (5 mg, 0.04 mmol), and C-(3-chloropyrazin-2-yl)-C-(2-phenylquinolin-7-yl)-methylamine (202 mg, 0.583 mmol) in dry CH2Cl2 (5 mL), cooled by ice/water, is added cyclobutanecarbonyl chloride (75 μL, 78 mg, 0.66 mmol), then the cooling bath is removed, and the reaction mixture is stirred at rt for 3 h. Water is added, the layers are separated, and the aqueous layer is extracted with CH2Cl2 (3×15 mL). The combined CH2Cl2 layers are washed with water, saturated NaHCO3 solution, and brine, dried over MgSO4, filtered and concentrated to give crude material as yellow foam, which is used for the next step without purification. 1H NMR (CDCl3, 400 MHz) δ 1.81-1.90 (m, 1H), 1.90-2.02 (m, 1H), 2.11-2.23 (m, 2H), 2.23-2.35 (m, 2H), 3.12 (quint, J=8.4 Hz, 1H), 6.80 (d, J=8.0 Hz, 1H), 7.22 (d, J=8.0 Hz, 1H), 7.43-7.48 (m, 1H), 7.48-7.54 (m, 2H), 7.73 (dd, J=2.0, 8.4 Hz, 1H), 7.82 (d, J=8.0 Hz, 1H), 7.85 (d, J=8.8 Hz, 1H), 7.90 (d, J=0.8 Hz, 1H), 8.07-8.12 (m, 2H), 8.19 (d, J=8.4 Hz, 1H), 8.38 (d, J=2.4 Hz, 1H), 8.58 (d, J=2.4 Hz, 1H). MS (ES+): m/z 429.0/431.0 (38/13) [MH+], 469.8/471.8 (6/2) [MH++MeCN]. HPLC: tR=3.6 min (MicromassZQ, polar—5 min).
