Isopropyl iodide → methyl 1-isopropyl-1H-indazole-6-carboxylate

Temperature

60 °C

A solution of methyl 1H-indazole-6-carboxylate (1.92 g, 10.9 mmol) and cessium carbonate (7.12 g, 21.8 mmol) in N,N-dimethylformamide (21.8 mL) under argon was heated to 60° C. for 10 min. 2-Iodopropane (1.09 mL, 10.9 mmol) was added dropwise. The mixture was stirred at 60° C. for 1.5 h. The mixture was cooled to ambient temperature and quenched with saturated aqueous sodium bicarbonate (30 mL). The mixture was extracted with ethyl acetate (3×30 mL). The combined organic layer was washed with saturated aqueous ammonium chloride (3×20 mL), saturated aqueous sodium chloride (1×20 mL), dried over sodium sulfate, filtered and concentrated under reduced pressure. Purification by silica gel chromatography (100% hexanes→70% hexanes/ethyl acetate) gave the title compound (1.33 g): LC-MS [M+1]=219.2.

1. temperatureThe mixture was cooled to ambient temperature
2. customquenched with saturated aqueous sodium bicarbonate (30 mL)
3. extractionThe mixture was extracted with ethyl acetate (3×30 mL)
4. washThe combined organic layer was washed with saturated aqueous ammonium chloride (3×20 mL), saturated aqueous sodium chloride (1×20 mL)
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customPurification by silica gel chromatography (100% hexanes→70% hexanes/ethyl acetate)

ORD record

ord-e4f9dda90d4d4731bc64f141d24d26dd

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08569512B2