反应详情

A solution of ethyl 3-methoxy-4-(1-methylpiperidin-4-ylmethoxy)benzoate (30.6 g, 89 mmol) in methylene chloride (75 ml) was cooled to 0-5° C. TFA (37.5 ml) was added followed by the dropwise addition over 15 minutes of a solution of fuming 24N nitric acid (7.42 ml, 178 mmol) in methylene chloride (15 ml). After completion of the addition, the solution was allowed to warm up and stirred at ambient temperature for 2 hours. The volatiles were removed under vacuum and the residue was dissolved in methylene chloride (50 ml). The solution was cooled to 0-5° C. and ether was added. The precipitate was collected by filtration, and dried under vacuum at 50° C. The solid was dissolved in methylene chloride (500 ml) and 3M hydrogen chloride in ether (30 ml) was added followed by ether (500 ml). The solid was collected by filtration and dried under vacuum at 50° C. to give ethyl 3-methoxy-4-(1-methylpiperidin-4-ylmethoxy)-6-nitrobenzoate (28.4 g, 82%).

1. additionfollowed by the dropwise addition over 15 minutes of a solution
2. additionAfter completion of the addition
3. temperatureto warm up
4. customThe volatiles were removed under vacuum
5. dissolutionthe residue was dissolved in methylene chloride (50 ml)
6. temperatureThe solution was cooled to 0-5° C.
7. additionether was added
8. filtrationThe precipitate was collected by filtration
9. customdried under vacuum at 50° C
10. dissolutionThe solid was dissolved in methylene chloride (500 ml)
11. addition3M hydrogen chloride in ether (30 ml) was added
12. filtrationThe solid was collected by filtration
13. customdried under vacuum at 50° C.