Ethyl chloroformate → ethyl 4-iodo-2-methyl-1H-imidazole-1-carboxylate

Temperature

0 °C

In general, modifications were made from the procedure given in J. Org. Chem., 1999, 64, 23, 8608-8615. A solution of commercially available 4-iodo-2-methyl-1H-imidazole (520 mg, 2.5 mmol) in THF (8.3 mL), containing DIEA (1.07 mL, 6.25 mmol) and DMAP (150 mg, 1.30 mmol), was cooled in a ice bath at 0° C. A solution of ethyl chloroformate (678 mg, 6.25 mmol) in THF (2.5 mL) was slowly added over a period of 20 min to the reaction mixture. The reaction mixture was heated at 50° C. for 48 h and the solvent was removed under reduced pressure. The residue was dissolved in DCM and the organic layer was washed with brine, water, dried over MgSO4, filtered and evaporated. Purification by flash chromatography (prepacked 10 g silicagel column, DCM/MeOH: 97/3 as eluent) to afford 660 mg of ethyl 4-iodo-2-methyl-1H-imidazole-1-carboxylate (Yield: 94%) as a colorless oil.

1. temperatureThe reaction mixture was heated at 50° C. for 48 h
2. customthe solvent was removed under reduced pressure
3. dissolutionThe residue was dissolved in DCM
4. washthe organic layer was washed with brine, water
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. customevaporated
8. customPurification by flash chromatography (prepacked 10 g silicagel column, DCM/MeOH: 97/3 as eluent)

ORD record

ord-163c53664df2470694d6af1f04125aa0

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08883826B2