Tetrahydrofuran → Tetraethyl 3-oxopentane-1,1-bisphosphonate

Temperatur

-78 °C

A solution of N-methoxy-N-methyl-3,3-bis(diethoxyphosphinyl)propionamide (1.00 g, 2.6 mmol) in THF (5 ml) was slowly added to a slurry of 80% sodium hydride (80 mg, 2.7 mmol) in THF (10 ml) at 0° C. Stirring was continued until all of the hydride was consumed (~20 minutes). The solution was cooled to -78° C. and ethylmagnesium bromide (1.0 ml of a 3.0M solution in diethyl ether, 3.0 mmol) was added. After the addition, the reaction mixture was warmed to 0° C. and stirred for one hour. The reaction was quenched by pouring slowly into a well-stirred ice-cold mixture of ethanol (40 ml) and concentrated HCl (5 ml). The solvents were removed in vacuo, the residue was taken up in brine (20 ml) and extracted with dichloromethane (4×20 ml). The combined extracts were dried (Na2SO4), concentrated in vacuo, and the resulting oil was purified by flash chromatography on silica gel eluting with 10% i-propanol in ethyl acetate to give the title compound (0.50 g, 54%) as a pale yellow oil.

1. customwas consumed (~20 minutes)
2. additionethylmagnesium bromide (1.0 ml of a 3.0M solution in diethyl ether, 3.0 mmol) was added
3. additionAfter the addition
4. temperaturethe reaction mixture was warmed to 0° C.
5. stirringstirred for one hour
6. customThe reaction was quenched
7. additionby pouring slowly into a well-stirred ice-cold mixture of ethanol (40 ml) and concentrated HCl (5 ml)
8. customThe solvents were removed in vacuo
9. extractionextracted with dichloromethane (4×20 ml)
10. dry with materialThe combined extracts were dried (Na2SO4)
11. concentrationconcentrated in vacuo
12. customthe resulting oil was purified by flash chromatography on silica gel eluting with 10% i-propanol in ethyl acetate

ORD-Eintrag

ord-513ee407692540e49f626f2d20b712d3

Quelldatensatz

uspto-grants-1998_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05728650