Hexane → HCID 19841705, compound

Temperature

-78 °C

Under argon atmosphere, a solution of n-butyllithium in hexane (1.58N, 41.8 ml, 0.066 mol) was dropwise added to a solution of dimethyl methylphosphonate (8.2 g, 0.066 mol) in anhydrous THF (120 ml) with stirring at -78° C., and the mixture was further stirred for 30 minutes. To the mixture there was dropwise added a solution of ethyl 2-methyl-4-octynoate (5.0 g, 0.0275 mol) containing 13% of methyl 2-methyl-4-octynoate in anhydrous THF (10 ml), and the whole mixture was stirred for 30 minutes. At 0° C., acetic acid (4 ml) and water (20 ml) were added to the reaction mixture followed by concentration. After water (30 ml) was added to the residue, the mixture was extracted with ethyl acetate (50 ml×2). Ethyl acetate layers were combined, washed with water (20 ml) and with brine (20 ml), and dried over anhydrous sodium sulfate to concentrate. The residue was subjected to vacuum distillation (b.p.=127°-130° C. at 0.22 mmHg), yielding dimethyl 3-methyl-2-oxo-5-nonanylphosphonate (6.82 g, 0.026 mol, 95.4% yield) as a colorless, transparent oil. The structure of this product was confirmed by the following data.

1. stirringthe mixture was further stirred for 30 minutes
2. stirringthe whole mixture was stirred for 30 minutes
3. concentrationfollowed by concentration
4. additionAfter water (30 ml) was added to the residue
5. extractionthe mixture was extracted with ethyl acetate (50 ml×2)
6. washwashed with water (20 ml) and with brine (20 ml)
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationto concentrate
9. distillationThe residue was subjected to vacuum distillation (b.p.=127°-130° C. at 0.22 mmHg)

ORD record

ord-8776d8040948459c9b748da6a5b972cc

Source dataset

uspto-grants-1989_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04880939