反应详情

温度

140 °C

Another run was conducted according to the process of this invention in the same apparatus employed in the previous runs. In this run, the reactor was charged with 5.0 grams of a finely ground tungstic oxide (WO3) on silica catalyst (8 percent by weight WO3, 1.7 mmol WO3), 6.5 grams (75 mmol) lithium bromide, 4.6 grams (22.5 mmol) 1,4-dibromo-2-butene, 50 ml acetic acid, 25 ml acetic anhydride and 12.5 grams (231.5 mmol) butadiene from the vapor phase. The reactor was pressured to 30 psig with oxygen, placein in an oil bath and heated to 140° C. After about 45 minutes required to reach the reaction temperature, the reaction was conducted for 5 hours. At the end of the reaction period, the reactor was opened and the unreacted butadiene distilled into a Dry Ice/acetone cold trap which recovered 1.3 grams butadiene. The reaction mixture was filtered and the filtrate distilled under reduced pressure. The middle fraction of the three taken was found to contain 26.8 mmol of 3-buten-2-yl acetate, 9.7 mmol 1,2 -diacetoxy-3-butene and 42.6 mmol 1,4-diacetoxy-2-butene for a diacetoxybutene yield of 22 percent based on the butadiene charged. Surprisingly, the yield of monoacetoxy butene was 27 percent based on the butadiene charged.

1. waitthe reaction was conducted for 5 hours
2. customAt the end of the reaction period
3. distillationthe unreacted butadiene distilled into a Dry Ice/acetone cold trap which
4. customrecovered 1.3 grams butadiene
5. filtrationThe reaction mixture was filtered
6. distillationthe filtrate distilled under reduced pressure