[OH:1][C:2]1[C:3]2[CH:14]=[C:13]([O:15][CH3:16])[CH:12]=[CH:11][C:4]=2[S:5][C:6]=1[C:7]([O:9][CH3:10])=[O:8].CS(C)=O.CC(C)([O-])C.[K+].Br[CH2:28][C:29]#[N:30]>C(OCC)(=O)C>[CH3:10][O:9][C:7]([C:6]1[S:5][C:4]2[CH:11]=[CH:12][C:13]([O:15][CH3:16])=[CH:14][C:3]=2[C:2]=1[O:1][CH2:28][C:29]#[N:30])=[O:8]To a room temperature solution of methyl 3-hydroxy-5-methoxybenzo[b]thiophene -2-carboxylate (1.00 g, 4.2 mmol) [Connor, et al., J. Med. Chem. 35:959 (1992)]in 20 mL of DMSO is added potassium t-butoxide (494 mg, 4.41 mmol) followed by bromoacetonitrile (878 μL, 12.58 mmol). The mixture is stirred at room temperature for 1.5 hours, then poured into ethyl acetate and 1N HC1. The organic layer is washed with 1N HCl, followed by several portions of brine, and dried over MgSO4. Filtration followed by removal of solvent in vacuo and recrystallization of the residue from ethyl acetate:hexane gives 413 mg. An additional crop of 112 mg can be obtained from the mother liquor, mp 159.5°-160° C.
Loading…
