反应详情

First 3.8 g (0.1 mole) of sodium borohydride and then 4.5 g (0.033 mole) of aluminum chloride were added in portions to a solution of 23.3 g (0.1 mole) of 4-fluoro-3-bromobenzoic acid methyl ester in 50 ml of diglyme at 5° C. The mixture was subsequently stirred, without cooling, until the exothermic reaction had ended (a rise in temperature up to about 50° C.) and the reaction was then allowed to go to completion in the course of 1 hour at 100° C. The reaction solution was then poured onto a mixture of 125 ml of icewater and 12 ml of concentrated hydrochloric acid and the benzyl alcohol which had separated out was separated off and distilled in vacuo. 18.7 g (91% of theory) of 4-fluoro-3-bromobenzyl alcohol were obtained in this manner as a colorless oil with a boiling point of 65° to 70° C. (0.1 mbar). "One-pot process"

1. temperaturewithout cooling, until the exothermic reaction
2. customup to about 50° C.
3. customto go to completion in the course of 1 hour at 100° C
4. customthe benzyl alcohol which had separated out
5. customwas separated off
6. distillationdistilled in vacuo