반응 #64258

반응 방정식

2-hydroxypropyl carbamate

methacrylic anhydride

→

2-hydroxypropyl carbamate methacrylate

수율 67.2%

용매

pyridine

반응 조건

후처리

1. 1
   기타A four-necked, five-liter round-bottomed reaction flask equipped with a thermometer, condenser, mechanical stirrer, and air sparger
2. 2
   workup.WAITDuring this heating period
3. 3
   기타during the course of the reaction
4. 4
   기타the reaction mass is sparged with air
5. 5
   기타is held at 65° C. until the concentration of methacrylic anhydride
6. 6
   세척The resulting product is then washed with a saturated solution of sodium carbonate
7. 7
   기타the aqueous layer removed from the solids by decantation
8. 8
   세척The resulting solid product is then washed twice with a total of two gallons of distilled water
9. 9
   온도by heating the wash water to 50° C
10. 10
    workup.STIRRINGDuring the washing procedure, the melted solids are well stirred
11. 11
    기타to separate from the molten organic material
12. 12
    기타decanted before the desired product
13. 13
    기타The wet product is dried overnight in a hood

실험 절차

A four-necked, five-liter round-bottomed reaction flask equipped with a thermometer, condenser, mechanical stirrer, and air sparger is charged with 1,920 g (16.1 moles) of 2-hydroxypropyl carbamate, 2,236 g (14.5 moles) of distilled methacrylic anhydride, 83 g of anhydrous pyridine, and 4.2 g (1,000 parts per million) methoxyhydroquinone. The reaction mass is stirred and slowly heated to 65° C. with a hot-water bath. During this heating period and during the course of the reaction, the reaction mass is sparged with air. The reaction mass is held at 65° C. until the concentration of methacrylic anhydride decreased to less than 1.5 percent by weight. The resulting product is then washed with a saturated solution of sodium carbonate, and the aqueous layer removed from the solids by decantation. This washing procedure is repeated two more times to neutralize all of the methacrylic acid. The resulting solid product is then washed twice with a total of two gallons of distilled water. For each wash, the solids are melted by heating the wash water to 50° C. During the washing procedure, the melted solids are well stirred and the aqueous material is allowed to separate from the molten organic material and decanted before the desired product resolidifies. The wet product is dried overnight in a hood to yield 2,000 g of anhydrous 2-hydroxypropyl carbamate methacrylate that analysis indicates has a 97% purity.

출처