Sodium hydride → HCID 10410270, compound

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Reaction Steps

Under a static nitrogen atmosphere, 2.0 g (9.2 mmol) of solid 3-butyl-5-(1,1-difluorobutyl)-1H-1,2,4-triazole is added in small portions to 10 mmol of sodium hydride in 50 ml of dimethylformamide (DMF); stirring is continued until hydrogen evolution has ceased. The anion solution is cooled to −10° C. (ice/methanol) and is treated with a solution of 3.0 g (9.2 mmol) of 4-bromomethyl-2′-methoxycarbonylbiphenyl (from Step 1 of Example 1) in 20 ml of dry DMF. The reaction is allowed to warm to ambient temperature and stir overnight. Methanol (10 ml) is added to destroy any unreacted sodium hydride and the DMF is removed in vacuo; the residue is dissolved in ethyl acetate, washed with water, and dried (MgSO4). Silica gel chromatography separates the two isomers; the more abundant isomer is dissolved in 80 ml of ethanol and is treated with 80 ml of 10% NaOH at ambient temperature for 3 days. The ethanol is removed in vacuo and the aqueous phase is acidified to pH 1 with hydrochloric acid which causes the product to precipitate; filtration and drying in vacuo gives 4′-[(5-butyl-3-(1,1-difluorobutyl)-1H-1,2,4-triazol-1-yl)methyl][1,1′-biphenyl)-2-carboxylic acid.

Provenance & Evidence