Reacción #1735

Ecuación de reacción

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

6-hydroxy-nicotinic acid

dicyclohexylcarbodiimide

→

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

Rendimiento 38.0%

Disolventes

dimethylformamide

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.WAITat 0° and the mixture was left
2. 2
   Otroto react at room temperature overnight
3. 3
   FiltraciónThe separated urea was filtered off
4. 4
   Extracciónthe filtrate was extracted with ethyl acetate
5. 5
   Lavadowashed twice with H2O
6. 6
   Otrodried over Na2 SO4
7. 7
   Otrothe solvent was removed under reduced pressure

Procedimiento

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.).

Fuente