Hydrochloric Acid → Diniconazole

Beteiligte Stoffe

Reaktionsschritte

Reaction was carried out on a scale of ten times that of Example 6. In a nitrogen atmosphere, a solution of 0.681 g (0.018 mole) of sodium borohydride in 9.44 g of dimethylformamide was added dropwise at -20° C. to a suspension of 3.38 g (0.018 mole) of (+)-norephedrine hydrochloride in 62.8 g of 1,2-dichloroethane, and the temperature of the resulting mixture was raised from -20° C. to room temperature over 2 hours. Thereafter, a solution of 3.89 g (0.012 mole) of (E)-1-(2,4-dichlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one (E/Z=97.6/2.4) in 50.24 g of 1,2-dichloroethane was added, and stirring was carried out at room temperature for 21 hours and then at 40° C. for 3 hours. The reaction solution was decomposed with addition of 7.22 g of 10% hydrochloric acid and 2.1 g of water, and the organic layer was separated, washed with water and concentrated under reduced pressure to obtain 3.89 g of (-)-(E)-1-(2,4-dichlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-ol as a crystal. The conversion of 99.9%, and the composition of the product obtained was: E-form alcohol, 95.8%; saturated alcohol, 0.2%; Z-form alcohol, 3.5%; and others, 0.5%. The enantiomer ratio of the E-form alcohol was: (-)-isomer, 85.2% and (+)-isomer, 14.8%. The optical yield was 70.4%.

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