Sodium Carbonate → 4-Bromo-7-methoxy-1H-indole

Temperature

90 °C

To a solution of 1-bromo-4-methoxy-2-methyl-3-nitro-benzene (31 g, 0.126 mol) in DMF (150 mL) was added dimethylformamide dimethylacetal (27 mL) and pyrrolidine (10.5 mL, 0.127 mol). The mixture was heated at 90° C. for 18 h and cooled to r.t. The mixture was diluted with water and extracted with CH2Cl2. The organic phase was dried over Na2SO4, filtered and concentrated. The residue was dissolved into HOAc (50 mL) and added dropwise to a solution of Fe (20.5 g, 0.37 mol) in boiling HOAc (150 mL). The mixture was refluxed for 1 h and cooled to r.t., water added and the mixture was neutralised with Na2CO3, and extracted with CH2Cl2. The organic phase was dried over Na2SO4, filtered and concentrated. The residue was purified by Prep-TLC (PE/EtOAc=5/1) to give the title compound (13 g, 44%).

1. temperaturecooled to r.t
2. extractionextracted with CH2Cl2
3. dry with materialThe organic phase was dried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated
6. dissolutionThe residue was dissolved into HOAc (50 mL)
7. temperatureThe mixture was refluxed for 1 h
8. temperaturecooled to r.t.
9. extractionextracted with CH2Cl2
10. dry with materialThe organic phase was dried over Na2SO4
11. filtrationfiltered
12. concentrationconcentrated
13. customThe residue was purified by Prep-TLC (PE/EtOAc=5/1)

ORD record

ord-5ba16124143749819f045e3b840d6f1f

Source dataset

uspto-grants-2015_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09133180B2