Reaktion #2475556

Reaktionsgleichung

trifluoroacetic acid

sodium methoxide

dimethyl phosphate

3,4,5-trimethoxybenzaldehyde

→

1

Ausbeute 88.0%

[Hydroxy-(3,4,5-trimethoxy-phenyl)-methyl]-phosphonic Acid Dimethyl Ester

Ausbeute 88.0%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeA round-bottom flask equipped with thermometer, condenser and gas inlet
2. 2
   TemperaturA resulted solution was heated at 50° C. for 1 hour
3. 3
   Temperaturcooled down to r.t.
4. 4
   EinengenThe mixture was concentrated under reduced pressure
5. 5
   workup.DISSOLUTIONthe residue dissolved in EtOAc (300 mL)
6. 6
   Waschenwashed once with 18% brine
7. 7
   Trocknenonce with saturated brine, dried over sodium sulfate
8. 8
   EinengenThe filtered solution was concentrated until precipitation
9. 9
   workup.ADDITIONTo the resulted suspension 1:1 mixture of t-butylmethyl ether and heptane
10. 10
    workup.ADDITIONwas added (50 mL)
11. 11
    FiltrationSolid was filtered out
12. 12
    Waschenwashed with two portions (20 mL) of the same solvent mixture
13. 13
    Sonstigevacuum-dried

Vorschrift

A round-bottom flask equipped with thermometer, condenser and gas inlet was charged with methanol (150 mL) and sodium methoxide (1.074 g, 20 mmol) and cooled to 0° C. under nitrogen protection. To a stirred solution were added subsequently dimethyl phosphate (19.52 g, 0.177 mol) and 3,4,5-trimethoxybenzaldehyde (30 g, 0.153 mol). A resulted solution was heated at 50° C. for 1 hour, cooled down to r.t. and treated with trifluoroacetic acid (4.6 ml). The mixture was concentrated under reduced pressure, the residue dissolved in EtOAc (300 mL), washed once with 18% brine, then once with saturated brine, dried over sodium sulfate. The filtered solution was concentrated until precipitation started. To the resulted suspension 1:1 mixture of t-butylmethyl ether and heptane was added (50 mL). Solid was filtered out, washed with two portions (20 mL) of the same solvent mixture and vacuum-dried to give 41.2 g (88%) of 1, LC purity 99.4% (AUC), m.p. 103-104° C.

Quelle