反应详情

A flame dried 500 ml round bottom flask was allowed to cool before 8 g (0.031 mole) of solid 1,12-dodecanedicarboxylic acid was added. Dry THF (~100 ml) was added to suspend the diacid. After stirring for 5-10 minutes the mixture was warmed with tap water to about 40° to effect dissolution of the diacid. A few particles were usually visible in the reaction flask at this point DCC was weighed in a flame dried beaker. DCC (6.4 gm, 0.031 mole) was dissolved in 20 ml of THF. The concentrated DCC solution was transferred to the reaction vessel using a disposable pipette. Throughout all procedures the reaction vessel was purged with nitrogen. The reaction was sealed under nitrogen pressure and allowed to stir at room temperature for 15 hours. After 15 hours a thick, white paste formed and stopped the stirring bar. (Ideally, sufficient THF should be added initially to the reaction to prevent paste formation.) After 15 hours, 500 ml of reagent grade acetone was added followed by filtration through a scintered glass funnel (medium, 300 ml capacity). The filtrate was stored in the refrigerator overnight to crystallize the product. The cyclic anhydride was collected by filtration through a medium scintered glass funnel. The product was rinsed with reagent grade acetone and dried under vacuum, room temperature, overnight. Typical yields are 50-70% based only on the first crop of crystals. Reactions were monitored by FTIR using KBr pellets prepared from aliquots of the reaction mixture taken to dryness by rotoevaporation. See FIG. 6.

1. customA flame dried 500 ml round bottom flask
2. additionwas added
3. customdried beaker
4. customThroughout all procedures the reaction vessel was purged with nitrogen
5. customThe reaction was sealed under nitrogen pressure
6. stirringto stir at room temperature for 15 hours
7. customAfter 15 hours a thick, white paste formed
8. wait) After 15 hours
9. filtrationfollowed by filtration through a scintered glass funnel (medium, 300 ml capacity)
10. customwas stored in the refrigerator overnight
11. customto crystallize the product
12. filtrationThe cyclic anhydride was collected by filtration through a medium
13. washThe product was rinsed with reagent grade acetone
14. customdried under vacuum, room temperature, overnight
15. customTypical yields
16. customprepared from aliquots of the reaction mixture