Potassium Carbonate → HCID 13508373, compound

Participants

Reaction Conditions

Reaction Steps

A solution of the above N-benzyl-1-(phenylsulfonyl)indole -3-carboxamide [XXIV: R8 =CH2Ph] (4.2 g, 11 mmol) in dry THF (200 mL) was treated at -78° C. with a solution of 2.5M n-BuLi in hexanes (9.1 mL, 23 mmol), and the stirred mixture was allowed to warm to -20° C. for 15 minutes, before being recooled to -78° C., when it was treated with methyldisulfide (2.5 mL, 28 mmol). The mixture was allowed to warm to 20° C., then quenched with water (25 mL). Volatiles were removed under reduced pressure, and the residue was extracted with EtOAc. Workup of the organic layer gave a crude product. This was dissolved in MeOH (300 mL), mixed with a solution of K2CO3 (6.9 g, 50 mmol) in water (125 mL), and heated under gentle reflux under N2 for 2 hours to ensure complete hydrolysis of the phenylsulfonyl group (J. Org. Chem. 1985;50:5451-5457). MeOH was removed under reduced pressure, and the residue was diluted with water and extracted with CH2Cl2. Chromatography of the resulting oil on Al2O3 (eluting with CH2Cl2) gave N-benzyl-2-(methylthio)indole -3-carboxalnide [XXV: R8 =CH2Ph] (2.8 g, 88% yield) as an oil.

Provenance & Evidence