[CH2:1]([O:3][C:4]([C:6]1[S:7][C:8](SC)=[C:9]([C:18]#[N:19])[C:10]=1[C:11]1[CH:16]=[CH:15][C:14]([I:17])=[CH:13][CH:12]=1)=[O:5])[CH3:2].[CH:22]([Zn])([CH3:24])[CH3:23]>CCOCC.C1COCC1.[Cl-].[Cl-].[Zn+2].[Ni](Cl)Cl.C1(P(C2C=CC=CC=2)CCCP(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[CH2:1]([O:3][C:4]([C:6]1[S:7][C:8]([CH:22]([CH3:24])[CH3:23])=[C:9]([C:18]#[N:19])[C:10]=1[C:11]1[CH:16]=[CH:15][C:14]([I:17])=[CH:13][CH:12]=1)=[O:5])[CH3:2]Add dropwise isopropylzinc solution (ZnCl2 1M in Et2O (10.5 ml) and isopropylzinc 2M in THF (10.5 ml) previously mixed at 10° C. under N2 atmosphere) to a mechanically stirring suspension of 4-cyano-3-(4-iodo-phenyl)-5-methylsulfanyl-thiophene-2-carboxylic acid ethyl ester (1.5 gr, 3.5 mmol) and 1,3-bis-(diphenylphosphino)propane nickel (II) chloride (380 mg, 0.71 mmol) in dry THF (35 ml) and heat the resulting mixture 60° C. for 1 hour. Cool the reaction to room temperature and remove solvents in vacuo. Purify the solid by chromatography on silica gel (eluting with 10-80% Ethyl acetate/hexane) to provide the title compound in 25% yield: Mass spectrum (EI+): m/z 426 (M++1).
Loading…