Borane;tetrahydrofuran → Uniconazole

Participants

Reaction Steps

In a nitrogen atmosphere, 3.5 ml of a chloroform solution containing 0.233 g (0.86 mmole) of (S)-2-amino-1,1-diphenyl-4-methylpentan-1-ol was added at -60° C. to 0.87 ml (0.87 mmole) of a 1.0M borane-tetrahydrofuran solution, and the temperature of the resulting solution was raised to room temperature over 2 hours. Thereafter, 2 ml of a chloroform solution containing 0.164 g (0.57 mmole) of (E)-1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-one was added to this solution at room temperature, and stirring was carried out for 24 hours. After-treatment was carried out in the same manner as in Example 1 to obtain 0.164 g of (+)-(E)-1-(4-chlorophenyl)-2-(1,2,4-triazol-1-yl)-4,4-dimethyl-1-penten-3-ol. The conversion was 87.0%, and the composition of the product was: E-form alcohol, 97.3% and Z-form alcohol, 2.7%. The enantiomer ratio of the E-form alcohol was: (+)-isomer, 87.2% and (-)-isomer 12.8%.

Provenance & Evidence