Реакция #1735

Уравнение реакции

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

6-hydroxy-nicotinic acid

dicyclohexylcarbodiimide

→

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

Выход 38.0%

Растворители

dimethylformamide

Условия реакции

Обработка

1. 1
   workup.WAITat 0° and the mixture was left
2. 2
   Другоеto react at room temperature overnight
3. 3
   ФильтрацияThe separated urea was filtered off
4. 4
   Экстракцияthe filtrate was extracted with ethyl acetate
5. 5
   Промывкаwashed twice with H2O
6. 6
   Другоеdried over Na2 SO4
7. 7
   Другоеthe solvent was removed under reduced pressure

Методика

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.).

Источник