[CH3:1][C:2]([NH:5][S:6]([C:9]1[CH:13]=[CH:12][N:11]([CH3:14])[CH:10]=1)(=[O:8])=[O:7])([CH3:4])[CH3:3].C([Li])CCC.CN(C)[CH:22]=[O:23].Cl>C1COCC1>[CH3:4][C:2]([NH:5][S:6]([C:9]1[CH:13]=[CH:12][N:11]([CH3:14])[C:10]=1[CH:22]=[O:23])(=[O:8])=[O:7])([CH3:1])[CH3:3]To a solution of 12.96 g (60 mmol) of N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide in 300 mL THF under a nitrogen atmosphere cooled to -78° C. was added dropwise, at such a rate as to keep the temperature below -65° C., 52.35 ml, (123 mmol) 2.35M n-butyllithium in hexanes. The reaction was stirred at -78° C. for ca. 30 minutes. To the reaction mixture was added 4.64 ml, (60 mmol) of N,N-dimethylformamide dropwise. The reaction mixture was allowed to warm to room temperature and stir for ca. 2 hours. The reaction mixture was cooled to 0° C. and acidified with 1N HCl. The THF phase was separated, washed with brine, dried (MgSO4) and concentrated in vacuo. The crude residue was chromatographed on silica (25% ethyl acetate/80% hexanes) affording 5.72 g of the title compound as a white solid, m.p. 101.5°-103° C.
불러오는 중…
