Reaktion #357257

Reaktionsgleichung

Cumene hydroperoxide

Trimethyl phosphite

3-nitrobenzenesulphonyl chloride

2-methyl-2-propene-1-ol

Triethylamine

→

yellow oil

[(2S)-2-Methyloxiranyl]methyl3-nitrobenzenesulfonate

Lösungsmittel

CH2Cl2

CH2Cl2

CH2Cl2

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONTo an oven-dried 1000 mL three-necked flask was added
2. 2
   workup.ADDITIONwas added
3. 3
   Temperaturmaintaining the temperature at −20° C
4. 4
   workup.STIRRINGThe mixture was stirred at this temperature overnight
5. 5
   Temperaturmaintaining the temperature at −20° C
6. 6
   TemperaturThe temperature was raised to −10° C.
7. 7
   workup.STIRRINGthe mixture was stirred at this temperature overnight
8. 8
   SonstigeAfter removing the external cooling vessel
9. 9
   Filtrationthe reaction mixture was filtered through celite
10. 10
    WaschenThe organic phase was washed with 10% tartaric acid (500 mL), saturated NaHCO3 (300 mL) and brine (300 mL)
11. 11
    TrocknenThe organic layer was dried over magnesium sulphate (MgSO4)
12. 12
    Einengenconcentrated in vacuo

Vorschrift

To an oven-dried 1000 mL three-necked flask was added powdered activated molecular sieves (8.0 g, 4 Å) and CH2Cl2 (440 mL), D-(−)-diisopropyl tartrate (4 mL, 14.2 mmol) and 2-methyl-2-propene-1-ol (20 mL, 240 mmol) was added and the mixture was cooled to −20° C. Titanium tetraisopropoxide (3.5 mL, 11.9 mmol) was added with a few mL of CH2Cl2 and the mixture was stirred at −20° C. for 30 min. Cumene hydroperoxide (75 mL, 430 mmol) was added dropwise over 1.5 hours maintaining the temperature at −20° C. The mixture was stirred at this temperature overnight. Trimethyl phosphite (40 mL, 340 mmol) was added dropwise over 5 hours maintaining the temperature at −20° C. Triethylamine (50 mL, 360 mmol) and 4-dimethylaminopyridine (DMAP) (3.48 g, 28.5 mmol) was added followed by a solution of 3-nitrobenzenesulphonyl chloride (47 g, 212 mmol) in CH2Cl2 (400 mL). The temperature was raised to −10° C. and the mixture was stirred at this temperature overnight. After removing the external cooling vessel, the reaction mixture was filtered through celite. The organic phase was washed with 10% tartaric acid (500 mL), saturated NaHCO3 (300 mL) and brine (300 mL). The organic layer was dried over magnesium sulphate (MgSO4) and concentrated in vacuo to give 150 g of a yellow oil. The crude material was purified by silica gel flash chromatography (0-50% ethyl acetate in heptane) to give the subtitled compound (48.8 g).

Quelle