Acetic Acid → Dimethyl 2-oxo-3-phenoxypropylphosphonate

HRID 462095Notes

Reaction equation

HRID 462095 reaction equation
[CH3:1][P:2](=[O:7])([O:5][CH3:6])[O:3][CH3:4].P(=O)([O-])[O-].[CH2:12]([Li])[CH2:13][CH2:14][CH3:15].[C:17]([OH:20])(=O)[CH3:18].[O:21]1CC[CH2:23][CH2:22]1>CCCCCC>[O:21]=[C:22]([CH2:23][O:20][C:17]1[CH:18]=[CH:15][CH:14]=[CH:13][CH:12]=1)[CH2:1][P:2](=[O:7])([O:5][CH3:6])[O:3][CH3:4]

Participants

7

Reactant 5

HCID 176Acetic AcidHCID 406CID 406HCID 8028TetrahydrofuranHCID 12958Dimethyl methylphosphonateHCID 178418339Butyllithium

Product 1

HCID 580104Dimethyl 2-oxo-3-phenoxypropylphosphonate

Reagents, catalysts & solvents 1

HCID 8058HexaneSolvent

Procedure

A solution of 33.2 g (268 mmoles) dimethyl methylphosphonate (Aldrich) in 360 ml dry tetrahydrofuran was cooled to -78° in a dry nitrogen atmosphere. To the stirred phosphonate solution was added 118 ml of 2.34 M n-butyllithium in hexane solution (Alfa Inorganics, Inc.) dropwise over a period of 18 minutes at such a rate that the reaction temperature never rose above -65°. After an additional 5 minutes stirring at -78°, 22.2 g (134 mmole) methyl 2-phenoxy acetate was added dropwise at a rate that kept the reaction temperature less than -70° (20 minutes). After 3.5 hours at -78° the reaction mixture was allowed to warm to ambient temperature, neutralized with 14 ml acetic acid and rotary evaporated to a white gel. The gelatinous material was taken up in 175 ml water, the aqueous phase extracted with 100 ml portions of chloroform (3x), the combined organic extracts were backwashed (50 cc H2O), dried (MgSO4), and concentrated (water aspirator) to a crude residue and distilled, b.p. 172°-175° (0.5 mm) to give 24.6 g dimethyl 2-oxo-3-phenoxypropylphosphonate.

Workup

  1. customthe reaction temperature less than -70° (20 minutes)
  2. waitAfter 3.5 hours at -78° the reaction mixture was allowed
  3. customrotary evaporated to a white gel
  4. extractionthe aqueous phase extracted with 100 ml portions of chloroform (3x)
  5. dry with materialdried (MgSO4)
  6. concentrationconcentrated (water aspirator) to a crude residue
  7. distillationdistilled

Sources & evidence

ORD record
ord-081b553045c0491580ca0e90d0620945
Source dataset
uspto-grants-1977_12
Patent number
US04065472

Reaction notes

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