Methyl iodide → 4-(4-chlorophenyl)-2,3-dimethyl-5-(1-methyl-6-oxo-1,6-dihydropyridin-3-yl)-4,5-dihydropyrrolo-[3,4-c]pyrazol-6(2H)-one

Participants

Reaction Steps

To a stirred solution of 4-(4-chlorophenyl)-3-methyl-5-(1-methyl-6-oxo-1,6-dihydropyridin-3-yl)-4,5-dihydropyrrolo[3,4-c]pyrazol-6(2H)-one (Example 2) (25 mg, 0.070 mmol) in DMF (1 mL) under Ar was added NaH (3.38 mg, 0.085 mmol). The reaction mixture was stirred at rt for 30 min and MeI (6.61 μL, 0.106 mmol) was added. After 1 hr at rt, the reaction mixture was quenched with a saturated aq. NaHCO3 solution and extracted with EtOAc. The combined organic layers were washed with a saturated aq. NaHCO3 solution, dried over Na2SO4, and evaporated. The crude material was purified by preparative HPLC (Gilson gx-281; column: Sunfire C18, 30×100 mm, 5 μm; flow: 30 mL/min; gradient: 5% to 100% B in 20 min; A=0.1% TFA in H2O, B=CH3CN; detection: UV) to afford the title product (10 mg, 0.027 mmol, 38% yield). tR: 3.39 min (HPLC 1); tR: 0.74 min (LC-MS 2); ESI-MS: 369 [M+H]+ (LC-MS 2); 1H NMR (400 MHz, DMSO-d6) δ ppm 2.05 (s, 3H) 3.34 (s, 3H) 3.83 (s, 3H) 6.10 (s, 1H) 6.30 (d, J=9.8 Hz, 1H) 7.23 (d, J=8.6 Hz, 2H) 7.35 (d, J=8.6 Hz, 2H) 7.44 (dd, J=9.8, 2.7 Hz, 1H) 7.89 (d, J=2.7 Hz, 1H). In addition to the title compound, a second product was isolated during this purification process and is described in Example 4.

Provenance & Evidence