Acetic Acid → Dimethyl 3-(3-chlorophenoxy)-2-oxopropylphosphonate

Temperature

-60 °C

A solution of n-butyl lithium (16.0 g) in hexane (160 ml) was added to a stirred solution of dimethyl methylphosphonate (26.9 g) in anhydrous tetrahydrofuran (150 ml) at -60° C. in an atmosphere of nitrogen during 20 minutes. The solution was maintained at -60° C. for a further period of 10 minutes and was then treated with a solution of ethyl 3-chlorophenoxyacetate (23.4 g) in anhydrous tetrahydrofuran (50 ml) at -60° C. during a further period of 10 minutes. This solution was stirred at -60° C. for 90 minutes and then stirred at ambient temperature for 2 hours. The solution was treated with acetic acid (21 ml) and the solvents were evaporated under reduced pressure. Water (60 ml) was added to the residue and the mixture was extracted with diethyl ether. The ethereal solution was washed with water, with aqueous sodium bicarbonate solution (10% w/v) and with water, dried over magnesium sulphate, and evaporated. The resulting residue was left to stand at ambient temperature overnight. The resulting colourless crystals were filtered off, washed with a small volume of diethyl ether, and recrystallised from a mixture of petroleum ether (b.p. 40°-60° C.) and toluene, to give dimethyl 3-(3-chlorophenoxy)-2-oxopropylphosphonate (18.6 g) in the form of colourless needles, m.p. 78°-79° C. [elemental analysis: C, 44.9; H, 5.1; P, 10.7%. C11H14ClO5P requires C, 45.1; H, 4.8; P, 10.6%. νmax 825, 865, 1030, 1160, 1270, 1335, 1600 and 1735 cm-1 ].

1. stirringstirred at ambient temperature for 2 hours
2. customthe solvents were evaporated under reduced pressure
3. additionWater (60 ml) was added to the residue
4. extractionthe mixture was extracted with diethyl ether
5. washThe ethereal solution was washed with water, with aqueous sodium bicarbonate solution (10% w/v) and with water
6. dry with materialdried over magnesium sulphate
7. customevaporated
8. waitThe resulting residue was left
9. waitto stand at ambient temperature overnight
10. filtrationThe resulting colourless crystals were filtered off
11. washwashed with a small volume of diethyl ether
12. customrecrystallised from a mixture of petroleum ether (b.p. 40°-60° C.) and toluene

ORD record

ord-168edd778b5e4f2495c158b3d6075deb

Source dataset

uspto-grants-1981_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04243683