反应详情

Under N2, NBS (6 g, 0.034 mol) was added to a solution of 5-methylbenzo[b]thiophene (30.8 g, 0.21 mol), benzoylperoxide (1.6 g) in CCl4 (300 ml) and was heated at reflux. After 15 minutes, the remainder of the NBS (35 g, 0.2 mol) was added over a period of 5 minutes and heated at reflux for 1.5 hours. The reaction mixture was then cooled, filtered and the filtrate washed with H2O (2x), dried, filtered and concentrated to dryness. The residue was dissolved in CHCl3 (130 ml) and added to a solution of hexamethylenetetramine (33.6 g, 0.24 mol) in CHCl3 (60 ml). After 0.5 hour, the reaction mixture was cooled, filtered and the solid washed with hexane. After drying, the solid was dissolved in acetic acid-H2O (275 ml) and heated at reflux for 2 hours. Then concentrated HCl (55 ml) was added and the mixture refluxed an additional 5 minutes. After cooling, the solution was extracted with ether (3×), and the organic extracts were backwashed with saturated Na2CO3 (2×), dried, filtered, and concentrated to dryness to yield 16.4 g (48%) of product

1. temperaturewas heated
2. temperatureat reflux
3. temperatureheated
4. temperatureat reflux for 1.5 hours
5. temperatureThe reaction mixture was then cooled
6. filtrationfiltered
7. washthe filtrate washed with H2O (2x)
8. customdried
9. filtrationfiltered
10. concentrationconcentrated to dryness
11. dissolutionThe residue was dissolved in CHCl3 (130 ml)
12. waitAfter 0.5 hour
13. temperaturethe reaction mixture was cooled
14. filtrationfiltered
15. washthe solid washed with hexane
16. customAfter drying
17. dissolutionthe solid was dissolved in acetic acid-H2O (275 ml)
18. temperatureheated
19. temperatureat reflux for 2 hours
20. additionThen concentrated HCl (55 ml) was added
21. temperaturethe mixture refluxed an additional 5 minutes
22. temperatureAfter cooling
23. extractionthe solution was extracted with ether (3×)
24. customdried
25. filtrationfiltered
26. concentrationconcentrated to dryness