Methyl iodide → HCID 58911620, compound

Participants

Reaction Steps

To a solution of the title compound of Example 215 (23.0 mg, 0.0965 mmol) in dimethylformamide (0.75 mL) were added cesium carbonate (94 mg, 0.29 mmol) and methyl iodide (0.0072 mL, 0.12 mmol). After 4.5 h, the reaction was partitioned between dichloromethane (2 mL) and water (2 mL). The aqueous layer was extracted with dichloromethane (2 mL). The combined organic layers were dried (sodium sulfate) and concentrated in vacuo. The residue was taken up in a minimum amount of 50% aqueous methanol and loaded onto a methanol-activated water-equilibrated 1-g SCX-type cation exchange column. The column was washed with water (6 mL) and 50% aqueous methanol (6 mL). The column was eluted with 2N methanolic ammonia (8 mL). This fraction was concentrated in vacuo to provide (−)-1,2,3,4,11,11a-hexahydro-2-methyl-pyrazino[1,2-b][1,2]benzothiazine 6,6-dioxide as a white solid (19 mg, 79%): LCMS (pos. ion spectrum) m/z 253.

Provenance & Evidence