1,5,6,7-Tetrahydro-4H-indol-4-one → 2-Bromo-1,5,6,7-tetrahydro-4H-indol-4-one

was prepared using a literature procedure (Remers et al., J. Org. Chem., 36:1241-1247 (1971) (“Remers”), which is hereby incorporated by reference). To a 100 mL round bottom flask charged with a magnetic stir bar was added 1,5,6,7-tetrahydro-4H-indol-4-one (1.2 g, 8.8 mmole) and dry THF (20 mL). Stirring was commenced, and a solution of phenyltrimethylammonium tribromide (3.33 g, 8.8 mmole) in 15 mL of dry THF was added dropwise over 10 minutes at ambient temperature. After the addition was complete, the reaction mixture was stirred for an additional 2 hours and then filtered to remove the precipitate. The filtrate was concentrated in vacuo and the residue treated with dichloromethane (30 mL) and 5% aqueous Na2CO3 solution (30 mL). The layers were separated and the dichloromethane layer was then washed with brine (30 mL), dried over anhydrous MgSO4, filtered and concentrated in vacuo to give the crude product as a white solid which was directly used without further purification. 1H NMR data matched the literature values exactly (“Remers”, which is hereby incorporated by reference).

1. customwas prepared
2. additionTo a 100 mL round bottom flask charged with a magnetic stir bar
3. additionAfter the addition
4. stirringthe reaction mixture was stirred for an additional 2 hours
5. filtrationfiltered
6. customto remove the precipitate
7. concentrationThe filtrate was concentrated in vacuo
8. additionthe residue treated with dichloromethane (30 mL) and 5% aqueous Na2CO3 solution (30 mL)
9. customThe layers were separated
10. washthe dichloromethane layer was then washed with brine (30 mL)
11. dry with materialdried over anhydrous MgSO4
12. filtrationfiltered
13. concentrationconcentrated in vacuo

ORD record

ord-c5d9e6b6a38343208d412cdc455c9578

Source dataset

uspto-grants-2010_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07816536B2