[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[NH:12][C:11]([C:13]([O:15][CH2:16][CH3:17])=[O:14])=[CH:10][C:9]=2[S:18]C#N)=[CH:4][CH:3]=1.[BH4-].[Na+].[OH-].[K+].C(P(CCCC)CCCC)CCC.Cl[CH:39]([F:41])[F:40]>CC(O)C.[Cl-].[Na+].O>[Cl:1][C:2]1[CH:3]=[CH:4][C:5]([C:8]2[NH:12][C:11]([C:13]([O:15][CH2:16][CH3:17])=[O:14])=[CH:10][C:9]=2[S:18][CH:39]([F:41])[F:40])=[CH:6][CH:7]=1
A solution of ethyl 5-(p-chlorophenyl)-4-thiocyanatopyrrole-2-carboxylate (76.7 mg, 0.25 mmol) in 2-propanol is treated with sodium borohydride (11.0 mg, 0.29 mmol) under nitrogen, heated to 70° C. for ten minutes, cooled to room temperature, treated with a solution of potassium hydroxide (16.8 mg, 0.30 mmol) in 2-propanol, treated with tributylphosphine (81.2 mg, 0.4 mmol), heated to 65°-70° C. and treated with excess chlorodifluoromethane for one hour. Additional tributylphosphine (81.2 mg, 0.4 mmol) is added to the reaction mixture and the addition of chlorodifluoromethane is continued for 30 minutes. The mixture is then poured into brine and extracted with ethyl acetate. The combined organic extracts are washed with water, dried over anhydrous sodium sulfate and concentrated in vacuo to obtain a liquid. Flash chromatography of the liquid using silica gel and a 1:10 ethyl acetate/hexanes solution gives the title product as a white solid (42.6 mg, mp 113°-117° C.) which is identified by 1HNMR and 13CNMR spectral analyses.
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