反应详情

3.82 g of 2-chloroimidazoline hydrogen sulfate (see Example 6A) was treated with 50 ml of 1M NaOH solution and immediately extracted with CH2Cl2 (3×20 ml). The extracts were dried (K2CO3) and the solution decanted. 10 ml of isopropanol was added and the CH2Cl2 was removed at reduced pressure. The resultant isopropanol solution was added to a refluxing solution of the N-methanesulfonyl-6-aminoindole (2.02 g, 9.61 mmol) in isopropanol (10 mmol). The mixture was refluxed for 3 hr, cooled, and concentrated under vacuum. A portion (800 mg) of the crude product was dissolved in MeOH:H2O (5:1) then 10 g of silica gel was added. The mixture was dried under vacuum and the resulting powder was applied to a silica gel column and eluted with ethyl acetate:MeOH:iPrNH2 (93:5:2) (iPr=isopropyl). The white solid obtained was suspended in MeOH (4 ml) and treated with 3 ml of 1.0M HCl/ether. The solid dissolved then a precipitate formed which was filtered off after chilling the mixture in an ice bath. 590 mg of N-methanesulfonyl-6-(imidazolidin-2-ylideneamino)indole hydrochloride were obtained (mp 167.6-170.6° C.).

1. extractionimmediately extracted with CH2Cl2 (3×20 ml)
2. dry with materialThe extracts were dried (K2CO3)
3. customthe solution decanted
4. addition10 ml of isopropanol was added
5. customthe CH2Cl2 was removed at reduced pressure
6. temperatureThe mixture was refluxed for 3 hr
7. temperaturecooled
8. concentrationconcentrated under vacuum
9. dissolutionA portion (800 mg) of the crude product was dissolved in MeOH:H2O (5:1)
10. addition10 g of silica gel was added
11. customThe mixture was dried under vacuum
12. washeluted with ethyl acetate:MeOH:iPrNH2 (93:5:2) (iPr=isopropyl)
13. customThe white solid obtained
14. dissolutionThe solid dissolved
15. customa precipitate formed which
16. filtrationwas filtered off
17. temperatureafter chilling the mixture in an ice bath