反応 #1536032

反応方程式

benz[b]anthracene

vinylene carbonate

→

5,12-dihydro-5,12-ethanobenz[b]anthracene-13,14-diol

反応条件

後処理

1. 1
   workup.ADDITIONA mixture of 7.0 g
2. 2
   温度at reflux under nitrogen for 20 hours
3. 3
   その他The excess vinylene carbonate is removed by vacuum distillation (57° C./9 mm.)
4. 4
   ろ過of methylene chloride and filtered
5. 5
   workup.ADDITIONThe filtrate is treated with twice its volume of methanol
6. 6
   温度cooled
7. 7
   その他producing a tan solid
8. 8
   その他This solid is recrystallized from 60 ml
9. 9
   ろ過of 1,2-dichloromethane, collected by filtration
10. 10
    洗浄washed with methanol
11. 11
    濃縮The mother liquor (saved above) is concentrated
12. 12
    その他giving a gummy solid which
13. 13
    その他is recrystallized from a mixture of methylene chloride and methanol giving a gray solid which
14. 14
    その他recrystallized from ethyl acetate with charcoal treatment

実験手順

A mixture of 7.0 g. of benz[b]anthracene and 26 g. of vinylene carbonate is heated at reflux under nitrogen for 20 hours. The excess vinylene carbonate is removed by vacuum distillation (57° C./9 mm.) and the residue is taken up in 25 ml. of methylene chloride and filtered. The filtrate is treated with twice its volume of methanol and then cooled, producing a tan solid and a mother liquor which is saved. This solid is recrystallized from 60 ml. of 1,2-dichloromethane, collected by filtration, washed with methanol and saved. The mother liquor (saved above) is concentrated giving a gummy solid which is recrystallized from a mixture of methylene chloride and methanol giving a gray solid which is combined with the above solid and recrystallized from ethyl acetate with charcoal treatment giving 5,12-dihydro-5,12-ethanobenz[b]anthracene-13,14-diol, cyclic carbonate as colorless rods. A mixture of 1.3 g. of the cyclic carbonate, 1.05 g. of potassium hydroxide, one ml. of water and 15 ml. of ethanol is stirred at 60°-65° C. for 2 hours. The mixture is diluted with 1-2 volumes of water, filtered and the solid is washed with water and dried giving cis-5,12-dihydro-5,12-ethanobenz[b]anthracene-13,14-diol as a colorless solid. To a solution of 2.6 g. of cis-5,12-dihydro-5,12-ethanobenz[b]anthracene-13,14-diol in 400 ml. of glacial acetic acid at 20° C. is added portionwise 4.4 g. of lead tetraacetate. The reaction is stirred for 45 minutes. The weakly purple colored solid is filtered off, washed with glacial acetic acid and finally water and dried leaving 1.0 g. (m.p. 170°-172° C.) of 5,12-dihydro-5,12-benz[b]anthracene dicarboxaldehyde.

出典