Acetic Acid → 4-(4-chlorophenyl)-5-(1,5-dimethyl-6-oxo-1,6-dihydropyridin-3-yl)-3-ethyl-1-(2-hydroxyethyl)-4,5-dihydropyrrolo-[3,4-c]pyrazol-6(1H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-hydrazinylethanol (76 mg, 1.0 mmol) in MeOH (2 mL) was added 5-(4-chlorophenyl)-1-(1,5-dimethyl-6-oxo-1,6-dihydropyridin-3-yl)-4-propionylpyrrolidine-2,3-dione (Step 60.1) (204 mg, 0.5 mmol) and the reaction mixture was heated for 1 hr at 70° C. and for 0.5 hr at 90° C. in the MW. The volume of MeOH was reduced to 1 mL and AcOH (2 mL) and sulfamic acid (97 mg, 1.0 mmol) were added. The reaction mixture was heated for 1 h at 110° C. in the MW. The reaction mixture was concentrated under reduced pressure. The residue was basified with 20% K2CO3 solution and extracted with EtOAc. Combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated under reduced pressure. The crude material was first purified by silica gel column chromatography (hexane/EtOAc/MeOH 80:20:2 to 0:10:1) then further purified by preparative achiral SFC (column Propyl-pyridyl-urea, gradient 15-20% in 6 min_total 11 min) to afford the title product (97 mg, 0.225 mmol, 45% yield) as colorless foam. tR: 0.84 min (LC-MS 2); ESI-MS: 427 [M+H]+ (LC-MS 2); Rf=0.21 (EtOAc/MeOH 9:1); 1H NMR (400 MHz, CDCl3) δ ppm 0.91 (t, J=7.6 Hz, 3H) 2.01 (s, 3H) 2.25-2.48 (m, 2H) 3.37 (s, 3H) 3.44 (t, J=6.3 Hz, 1H) 3.95-4.05 (m, 2H) 4.43 (dd, J=5.6, 3.7 Hz, 2H) 5.50 (s, 1H) 6.91-7.03 (m, 4H) 7.25 (d, J=8.3 Hz, 2H).

Provenance & Evidence