Hexane → Dimethyl (3-cyclohexyl-2-oxopropyl)phosphonate

Temperatur

0 °C

To a stirred solution of dimethyl methylphosphonate (10.3 g, 0.083 mol) in 150 ml of anhydrous THF at -78° C. was added dropwise a solution of n-butyl lithium in hexane (1.67N, 50 ml, 0.083 mol) under argon atmosphere. After 30 minutes, a solution of methyl cyclohexylacetate (5.0 g, 0.035 mol) in 10 ml of anhydrous THF was further added and the mixture was stirred for 30 minutes. The reaction solution was allowed to warm to 0° C., diluted with 5 ml of acetic acid and 10 ml of water, and concentrated. 30 ml of water was added to the residue, and then the mixture was extracted with ethyl acetate (50 ml×2). The combined ethyl acetate layers were washed with water (20 ml×1) and brine (20 ml×1), dried over anhydrous sodium sulfate, and concentrated. The residue was distilled under reduced pressure to give a colorless transparent oil of dimethyl 3-cyclohexyl-2-oxopropylphosphonate (7.4 g, 0.0298 mol, yield 85.3%, b.p. 118°-122° C./0.23 mmHg), which was assigned the structure by the following data:

1. concentrationconcentrated
2. addition30 ml of water was added to the residue
3. extractionthe mixture was extracted with ethyl acetate (50 ml×2)
4. washThe combined ethyl acetate layers were washed with water (20 ml×1) and brine (20 ml×1)
5. dry with materialdried over anhydrous sodium sulfate
6. concentrationconcentrated
7. distillationThe residue was distilled under reduced pressure

ORD-Eintrag

ord-29049151a45c45a780e2dffc23feeaf0

Quelldatensatz

uspto-grants-1988_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04775692