C([Li])CCC.[Cl:6][C:7]1[CH:12]=[CH:11][C:10]([C:13]2[O:14][CH:15]=[CH:16][N:17]=2)=[CH:9][CH:8]=1.[CH2:18]=[O:19].[Cl-].[NH4+]>CCCCCC.O1CCCC1>[Cl:6][C:7]1[CH:8]=[CH:9][C:10]([C:13]2[O:14][C:15]([CH2:18][OH:19])=[CH:16][N:17]=2)=[CH:11][CH:12]=1
13.8 ml of a 2.42M (33.4 mmol) solution of n-butyl lithium in hexane were added dropwise during 5 minutes to a stirred solution of 6 g (33.4 mmol) of 2-(4-chlorophenyl)oxazole in 60 ml of dry tetrahydrofuran maintained at -60° C. under an argon atmosphere. The suspension was allowed to warm to -40° C. during 30 minutes and 6.9 g (230 mmol) of paraformaldehyde were added to a slurry in 15 ml of dry tetrahydrofuran. The mixture was allowed to attain room temperature during 1.5 hours and was stirred for a further 1 hour. 10 ml of saturated aqueous ammonium chloride were added to the mixture and the resulting suspension was partitioned between 300 ml of water and 200 ml of dichlormethane. The organic phase was separated and the aqueous phase was extracted twice with 200 ml of dichloromethane each time. The combined organic phases were dried over magnesium sulphate and filtered, and the solvent was removed by evaporation under reduced pressure to given an oil. The oil was chromatographed on silica gel using 70% by volume ethyl acetate in hexane for the elution. The eluate was evaporated to yield 4.25 g (60%) of 2-(4-chlorophenyl)-5-oxazolemethanol of melting point 115°-116° C.
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