Ethyl chloroformate → (S)-Ethyl [S-phenyl-N-(trimethylsilyl)sulfonimidoyl]acetate

Temperature

0 °C

To a 100 mL round bottom flask equipped with a magnetic stir-bar and a rubber septum was added a solution of 2,2,6,6-tetra-methylpiperidine (8.91 mL, 52.5 mmol) in anhydrous THF (22 mL). The solution was cooled to 0° C. and was treated with n-BuLi (18 mL, 45 mmol) (2.5 M in hexanes) via a syringe. The resulting solution was stirred for 10 min at 0° C., cooled to −78° C., and treated dropwise with a solution of (S)-trimethyl{[methyl(oxo)phenyl-λ6-sulfanylidene]amino}silane (18.7 mmol) in THF (10 mL). The reaction mixture was stirred at −78° C. for 30 min and then was treated with ethyl chloroformate (5.16 mL, 52.5 mmol) dropwise. The reaction mixture was stirred for an hour and warmed to room temperature. The reaction mixture was treated with saturated aqueous NH4Cl (2.5 mL). The white solid which formed was collected by filtration and discarded. The filtrate was treated with additional saturated aqueous NH4Cl solution and the resulting mixture was stored in a −20° C. fridge for 15 hours. The organic layer was collected and concentrated to give the title compound. This material was used directly in the next step of the synthesis

1. customTo a 100 mL round bottom flask equipped with a magnetic stir-bar
2. temperaturecooled to −78° C.
3. stirringThe reaction mixture was stirred at −78° C. for 30 min
4. stirringThe reaction mixture was stirred for an hour
5. temperaturewarmed to room temperature
6. customThe white solid which formed
7. filtrationwas collected by filtration
8. additionThe filtrate was treated with additional saturated aqueous NH4Cl solution
9. customwas stored in a −20° C.
10. customfor 15 hours
11. customThe organic layer was collected
12. concentrationconcentrated

ORD record

ord-6bc1f4b136ab4c18847919d56cb885cd

Source dataset

uspto-grants-2012_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08143410B2