反应详情

温度

22.5 °C

63 ml of concentrated sulfuric acid were added dropwise at approximately 20 to 25° C. to a solution of 64 g (0.17 mol) of the dibromide of Example 1 in 500 ml of anhydrous methanol. The temperature of the reaction solution was kept at 30° C. by cooling. After the mixture had been stirred for 30 minutes at 20 to 25° C., it was heated for 3 hours to 50° C. The reaction mixture was stirred into approximately 3.5 l of water. The precipitate was filtered off and washed with water and then with a pentane/MTBE mixture (5:1). After drying, 25 g of the title compound were obtained, which corresponds to 81% of theory. (m.p. 82° C.)

1. customwas kept at 30° C.
2. temperatureby cooling
3. temperatureit was heated for 3 hours to 50° C
4. filtrationThe precipitate was filtered off
5. washwashed with water
6. customAfter drying