Реакция #1996629

Уравнение реакции

trifluoroacetic acid

sodium methoxide

dimethyl phosphate

3,4,5-trimethoxybenzaldehyde

→

1

Выход 88.0%

[Hydroxy-(3,4,5-trimethoxy-phenyl)-methyl]-phosphonic acid dimethyl ester

Выход 88.0%

Растворители

methanol

Условия реакции

Обработка

1. 1
   ДругоеA round-bottom flask equipped with thermometer, condenser and gas inlet
2. 2
   ТемператураA resulted solution was heated at 50° C. for 1 hour
3. 3
   Температураcooled down to r.t.
4. 4
   КонцентрированиеThe mixture was concentrated under reduced pressure
5. 5
   workup.DISSOLUTIONthe residue dissolved in EtOAc (300 mL)
6. 6
   Промывкаwashed once with 18% brine
7. 7
   Сушкаonce with saturated brine, dried over sodium sulfate
8. 8
   КонцентрированиеThe 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
    ФильтрацияSolid was filtered out
12. 12
    Промывкаwashed with two portions (20 mL) of the same solvent mixture
13. 13
    Другоеvacuum-dried

Методика

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.

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