Ethyl Methanesulfonate → Ethyl diethylphosphorylmethanesulfonate

Temperature

-45 °C

To a stirred solution of ethyl methanesulphonate (4.11 ml, 40 mmol) in dry THF (100 ml) was added dropwise at −78° C. 2.5 M n-BuLi in hexane (17.8 ml. 44.4 mmol) within 10 min. After the mixture was stirred for 15 min, ethyl chlorophosphate (3.2 ml, 22.2 mmol) was added slowly at the same temperature. The solution was stirred at −78° C. for 30 min, then allowed to warm to −45° C. and with stirring for additional 1 h. The reaction was quenched by adding 4.4 M NH4Cl solution (11 ml), and the mixture was warmed to ambient temperature. After the organic solvents were removed by a rotary evaporator, the residue was treated with H2O (50 ml), and extracted with DCM (3×70 ml), washed with brine (40 ml) and dried. Evaporation of the solvent under reduced pressure afforded the crude product, which was purified by flash silica gel column chromatography (eluting with 30-100% EtOAc in hexane) to give ethyl diethylphosphorylmethanesulphonate (4.6 g, 80% yield) as light-yellow oil.

1. stirringThe solution was stirred at −78° C. for 30 min
2. stirringwith stirring for additional 1 h
3. customThe reaction was quenched
4. additionby adding 4.4 M NH4Cl solution (11 ml)
5. temperaturethe mixture was warmed to ambient temperature
6. customAfter the organic solvents were removed by a rotary evaporator
7. additionthe residue was treated with H2O (50 ml)
8. extractionextracted with DCM (3×70 ml)
9. washwashed with brine (40 ml)
10. customdried
11. customEvaporation of the solvent under reduced pressure
12. customafforded the crude product, which
13. customwas purified by flash silica gel column chromatography (eluting with 30-100% EtOAc in hexane)

ORD record

ord-8a80ae093f6345f3a315f2c544eb7beb

Source dataset

uspto-grants-2016_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09260382B2