Reaktion #1735

Reaktionsgleichung

4-trimethylsilyl-(E)-but-2-en-1-ol

6-hydroxy-nicotinic acid

dicyclohexylcarbodiimide

→

4-trimethylsilanyl-(E)-but-2-enyl 6-hydroxy-nicotinate

Ausbeute 38.0%

Lösungsmittel

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITat 0° and the mixture was left
2. 2
   Sonstigeto react at room temperature overnight
3. 3
   FiltrationThe separated urea was filtered off
4. 4
   Extraktionthe filtrate was extracted with ethyl acetate
5. 5
   Waschenwashed twice with H2O
6. 6
   Sonstigedried over Na2 SO4
7. 7
   Sonstigethe solvent was removed under reduced pressure

Vorschrift

1.3 g of 4-trimethylsilyl-(E)-but-2-en-1-ol (synthesis described in J. Org. Chem. 1984, 49, 4092), 1.08 g of 6-hydroxy-nicotinic acid and 178 mg of 4-dimethylaminopyridine were placed in succession in 30 ml of abs. dimethylformamide. 1.77 g (1.1 eq.) of dicyclohexylcarbodiimide were added thereto at 0° and the mixture was left to react at room temperature overnight. The separated urea was filtered off, the filtrate was extracted with ethyl acetate, washed twice with H2O, dried over Na2 SO4 and the solvent was removed under reduced pressure. Flash chromatography on SiO2 (hexane/ethyl acetate=1/1) yielded 782 mg of 4-trimethylsilanyl-(E)-but-2-enyl 6-hydroxy-nicotinate as white crystals of m.p. 107°-110° (dec.).

Quelle