Diethyl chlorophosphate → Diethyl ((phenylsulfonyl)methyl)phosphonate

Temperature

-78 °C

A stirred solution of methyl phenyl sulfone (20 g, 0.128 mol) in dry THF (200 mL) was cooled at −78° C. in an acetone/dry ice bath. Lithium bis(trimethylsilyl)amide (Li HMDS; 134 mL, 1 M solution in THF, 0.134 mol) was added dropwise over 1 h. The resulting white suspension was stirred for an additional hour at −78° C. and diethyl chlorophosphate (18.5 mL, 128 mmol) in THF (20 mL) was added. The reaction mixture was stirred at −78° C. for 0.5 h, then allowed to slowly warm to room temperature and left stirring for 4 h. The reaction mixture was next concentrated under reduced pressure, the residue was dissolved in EA (500 mL), washed with brine (100 mL),dried over anhydrous Na2CO3 and concentrated under reduced pressure. The resultant crude material was purified by flash chromatography on silica gel (EA:H, 3:1 to 1:1) to afford the desired product as white solid (17.9 g, 48%).

1. stirringThe reaction mixture was stirred at −78° C. for 0.5 h
2. temperatureto slowly warm to room temperature
3. waitleft
4. stirringstirring for 4 h
5. concentrationThe reaction mixture was next concentrated under reduced pressure
6. dissolutionthe residue was dissolved in EA (500 mL)
7. washwashed with brine (100 mL),dried over anhydrous Na2CO3
8. concentrationconcentrated under reduced pressure
9. customThe resultant crude material was purified by flash chromatography on silica gel (EA:H, 3:1 to 1:1)

ORD record

ord-b38bf12e4bb641f38604c361be8defb5

Source dataset

uspto-grants-2003_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06617426B1