Реакция #157314

Уравнение реакции

Sodium hydroxide

9-Borabicyclo[3.3.1]nonane

1-benzyl 4-tert-butyl 2-vinylpiperazine-1,4-dicarboxylate

3-bromopyridine

triphenylphosphine

→

desired product

Выход 63.0%

1-benzyl 4-tert-butyl 2-(2-(pyridin-3-yl)ethyl)piperazine-1,4-dicarboxylate

Выход 63.0%

Условия реакции

Обработка

1. 1
   ДругоеOnce bubbling
2. 2
   Температураthe reaction mixture was heated
3. 3
   Температураto reflux overnight
4. 4
   workup.ADDITIONthe reaction mixture was diluted with water (200 mL)
5. 5
   Экстракцияextracted with EtOAc (3×200 mL)
6. 6
   СушкаThe combined organics were dried over Na2SO4
7. 7
   Фильтрацияfiltered
8. 8
   Концентрированиеconcentrated under reduced pressure
9. 9
   ДругоеPurification by column chomatography (10 to 40% EtOAc in Hexane gradient)

Методика

9-Borabicyclo[3.3.1]nonane (0.5M solution in THF, 54 mL, 27 mmol) was added to 1-benzyl 4-tert-butyl 2-vinylpiperazine-1,4-dicarboxylate (2.33 g, 6.73 mmol). After 3 h, 3-bromopyridine (0.99 mL, 10.1 mmol), triphenylphosphine (0.53 g, 2.0 mmol), and tetrakis(triphenylphosphine) palladium(0) (0.311 g, 0.27 mmol) were added. Sodium hydroxide (1N aqueous solution, 16.8 mL, 16.8 mmol) was added slowly. Once bubbling ceased, the reaction mixture was heated to reflux overnight. Upon cooling to rt, the reaction mixture was diluted with water (200 mL) and extracted with EtOAc (3×200 mL). The combined organics were dried over Na2SO4, filtered, and concentrated under reduced pressure. Purification by column chomatography (10 to 40% EtOAc in Hexane gradient) gave 1.79 g (63%) of the desired product as a thick oil. Rf=0.57 in 80% EtOAc/Hexane. LC-MS: RT=7.69 min., [M+H]+=426.2. The material was contaminated with ˜15% triphenylphosphine, and was used without further purification.

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