Reaktion #333127

Reaktionsgleichung

furan-2-carbaldehyde

(S)-2-methylpropane-2-sulfinamide

→

(S)-2-methyl-propane-2-sulfinic acid 1-furan-2-yl-meth-(E)-ylideneamide

Ausbeute 89.2%

Lösungsmittel

ethyl acetate

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethen slowly quenched by dropwise addition of brine (5 ml) which
2. 2
   Sonstigeresulted in the formation of a thick precipitate
3. 3
   workup.STIRRINGstirred vigorously at room temperature for 15 min
4. 4
   FiltrationThe suspension was filtered over Celite
5. 5
   Waschenrinsed with ethyl acetate
6. 6
   EinengenThe filtrate was concentrated
7. 7
   Sonstigethe residue was chromatographed over silica gel with EtOAc/hexanes (gradient 0-25% EtOAc)

Vorschrift

In a round-bottomed flask, furan-2-carbaldehyde (800 mg, 8.33 mmol) was dissolved in THF (20 ml) and (S)-2-methylpropane-2-sulfinamide (1.21 g, 10.0 mmol) and titanium(IV) ethoxide (3.5 ml, 16.7 mmol) were added. The reaction mixture was stirred at room temperature for 5 h then slowly quenched by dropwise addition of brine (5 ml) which resulted in the formation of a thick precipitate. The reaction mixture was diluted with ethyl acetate and stirred vigorously at room temperature for 15 min. The suspension was filtered over Celite and rinsed with ethyl acetate. The filtrate was concentrated and the residue was chromatographed over silica gel with EtOAc/hexanes (gradient 0-25% EtOAc) to give 1.48 g (89%) of (S)-2-methyl-propane-2-sulfinic acid 1-furan-2-yl-meth-(E)-ylideneamide as a light yellow oil.

Quelle