Sodium methanesulfinate → HCID 68153568, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of sodium methanesulfinate (293 mg, 2.87 mmol), benzyl 6-bromo-2-methyl-spiro[3,4-dihydropyrrolo[1,2-a]pyrazine-1,4′-piperidine]-1′-carboxylate (1.00 g, 2.39 mmol), CuI (296 mg, 1.55 mmol) and DMSO (5 mL) was heated at 90° C. in a pressure vessel for 20 hours. The mixture was cooled and was partitioned between ether (10 mL) and water (10 mL). The organic layer was separated and the aqueous layer was extracted with ether (3×5 mL). The combined organic layers were washed with brine (2×10 mL), dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by column chromatography utilizing a gradient of 0-50% ethyl acetate in CH2Cl2 to yield benzyl 2-methyl-6-methylsulfonyl-spiro[3,4-dihydropyrrolo[1,2-a]pyrazine-1,4′-piperidine]-1′-carboxylate (520 mg, 52%) as a white solid. ESI-MS m/z calc. 417.2, found 418.3 (M+1)+; Retention time: 1.27 minutes (3 min run). 1H NMR (400 MHz, CDCl3) δ 7.45-7.30 (m, 5H), 6.88 (d, J=4.1 Hz, 1H), 6.01 (d, J=3.9 Hz, 1H), 5.15 (s, 2H), 4.28-4.15 (m, 2H), 4.09-3.89 (m, 2H), 3.40-3.16 (m, 4H), 3.10 (s, 3H), 2.37 (s, 3H), 2.20-2.02 (m, 2H), 1.89-1.66 (m, 2H).

Provenance & Evidence