Sodium borohydride → HCID 20187544, Verbindung

To a suspension of 2.4 g of 1-(2,4-dichlorophenyl)-2-fluoro-2-(1H-1,2,4-triazol-1-yl)ethanone in 9.5 ml of methanol and 0.5 ml of water is added at 5°-10° C., with stirring, 0.12 g of sodium borohydride, and the resulting mixture is stirred firstly for 1 hour at 0°-5° C. and then for 2 hours at room temperature, in the course of which a clear solution gradually forms. This solution is then poured into ice-water, and the mixture is extracted twice with dichloromethane. The combined extracts are dried over sodium sulfate, filtered, and concentrated by evaporation. The residue is distilled under high vacuum to obtain the above alcohol as a diastereoisomeric mixture; b.p. of the crude product: 150°-160° C./0.07 mbar. Crystallisation from diethyl ether/diisopropyl ether yields the purified diastereoisomeric mixture in the form of beige crystals; melting range 103°-112° C.