Methyl iodide → 1-Tert-butyl 2-methyl 2-methylpyrrolidine-1,2-dicarboxylate

Temperature

-78 °C

To a solution of diisopropylamine (1.59 g, 15.7 mmol) in THF (10 mL) was added n-BuLi (7.54 mL, 2.5 M in n-hexane) dropwise at 0° C. Then the solution was stirred at the same temperature for 30 min. 1-tert-butyl 2-methylpyrrolidine-1,2-dicarboxylate (3.0 g, 13.0 mmol) was dissolved in 50 mL THF and cooled to −78° C. To the solution was added prepared lithium diisopropylamide (15.7 mmol) dropwise. After the reaction mixture was kept at −78° C. for 3 h, MeI (1.6 mL, 25.7 mmol) was added. The mixture was allowed to warm to 0° C. and stirred for 2 h. Then the reaction mixture was quenched with water (30 mL) and extracted with EtOAc (3×50 mL). The combined organic layers were dried over Na2SO4 and concentrated under vacuum to give 2 g of the crude product. MS (ESI): 244 (MH+).

1. additionTo the solution was added
2. waitAfter the reaction mixture was kept at −78° C. for 3 h
3. temperatureto warm to 0° C.
4. stirringstirred for 2 h
5. customThen the reaction mixture was quenched with water (30 mL)
6. extractionextracted with EtOAc (3×50 mL)
7. dry with materialThe combined organic layers were dried over Na2SO4
8. concentrationconcentrated under vacuum

ORD record

ord-f4ec1eef9f0248f9931a5b711caeb566

Source dataset

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08772301B2