反应详情

Into a 250 ml 3-neck flask was added 5.4 grams (0.11 mole) of 64% aqueous hydrazine and 50 mls of THF. The flask was equipped with a magnetic stirrer, thermometer, reflux condenser and a dropping funnel containing 9.6 grams (0.03 mole) of 2-(3-hydroxy-4-benzoylphenoxy)ethyl chloroformate dissolved in 50 ml of THF. The chloroformate solution was added dropwise to the stirring hydrazine solution over 1/2 hour. The temperature quickly exothermed to 36° C. and slowly subsided after the addition was over. The reaction was stirred an additional 1/2 hour and concentrated to 31 grams. The THF solution was added to 300 ml of water. A sticky solid formed. The solid was filtered off, taken up in methylene chloride, dried over Na2SO4, filtered and the methylene chloride stripped off. The residue was a viscous orange-brown liquid. The crude product was slurried in 150 ml of warm MtBE. Most of the crude product went into solution, leaving a dark brown liquid residue. The yellow MtBE layer was decanted off and the MtBE stripped off on a rotating evaporator, leaving 9.0 grams of a yellow viscous liquid. Liquid chromatography indicated it was about 92% pure. The residue was slurried in warm methanol and upon cooling, a solid formed. The solid was filtered off and after air drying, weighed 6.4 grams (67% yield) and had a melting point of 58°-61° C.

1. customThe flask was equipped with a magnetic stirrer
2. temperaturethermometer, reflux condenser and a dropping funnel
3. customquickly exothermed to 36° C.
4. additionafter the addition
5. concentrationconcentrated to 31 grams
6. additionThe THF solution was added to 300 ml of water
7. customA sticky solid formed
8. filtrationThe solid was filtered off
9. dry with materialdried over Na2SO4
10. filtrationfiltered
11. customleaving a dark brown liquid residue
12. customThe yellow MtBE layer was decanted off
13. customthe MtBE stripped off on a rotating evaporator