Methyl iodide → 3-(4-Chloro-phenyl)-2-(2-chloro-phenyl)-5-isopropyl-4-methyl-4,5-dihydro-2H-pyrrolo[3,4-c]pyrazol-6-one

Participants

Reaction Steps

To a solution of 3-(4-chloro-phenyl)-2-(2-chloro-phenyl)-5-isopropyl-4,5-dihydro-2H-pyrrolo[3,4-c]pyrazol-6-one 3A-1 (19 mg, 0.05 mmol) in THF (0.5 ml) at −78° C. was added LiHMDSi (55 μl, 0.055 mmol). A deep blue-black solution was formed. The reaction mixture was stirred for 0.17 hour and then iodomethane (4.4 μl, 0.07 mmol) was added dropwise. The reaction mixture was stirred at −78° C. for 0.25 h (until a yellow color formed) and at room temperature for 2 hours, quenched with sat'd aq NH4Cl, and extracted with EtOAc. The organic solution was washed with sat'd aq NaCl, dried, and concentrated in vacuo. The residue was purified on 1 mm chromatotron plates using a 1:1 EtOAc/hexane solution to give 6A-1 as a white solid (3.2 mg, 14%); +ES MS (M+1) 400.3; 1H NMR (CDCl3): δ 7.4-7.3 (m, 4H), 7.28-7.24 (m, 2H), 7.1-7.06 (m, 2H), 4.84-4.77 (m, 1H), 4.37-4.27 (m, 1H), 1.48-1.4 (m, 9H).

Provenance & Evidence