Реакция #57730

Уравнение реакции

3-methyl-benzofuran-2-carboxylic acid

2,6-dimethyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenol

1,3-dicyclohexylcarbodiimide

→

3-methyl-benzofuran-2-carboxylic acid 2,6-dimethyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl ester

Выход 28.0%

Растворители

dichloromethane

water

Условия реакции

Обработка

1. 1
   Экстракцияextracted with ethyl acetate
2. 2
   ПромывкаThe organics were washed with brine
3. 3
   Сушкаdried over magnesium sulfate
4. 4
   Фильтрацияfiltered
5. 5
   Концентрированиеconcentrated in vacuo
6. 6
   ДругоеThe residue was purified

Методика

To 3-methyl-benzofuran-2-carboxylic acid (500 mg, 2.84 mmol, 1 eq) in 5 mL of dichloromethane under argon was added 2,6-dimethyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenol (704 mg, 2.84 mmol, 1 eq.), 1,3-dicyclohexylcarbodiimide (1.17 g, 5.68 mmol, 2 eq.), and 4-(dimethylamino)pyridine (173 mg, 1.42 mmol, 0.5 eq.). The resulting mixture was stirred at room temperature for 6 h. The reaction was then diluted with water and extracted with ethyl acetate. The organics were washed with brine, dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was purified using flash column chromatography on silica gel to provide 3-methyl-benzofuran-2-carboxylic acid 2,6-dimethyl-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl ester in 28% yield. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.3 (s, 12 H) 2.2 (s, 6 H) 2.7 (s, 3 H) 7.4 (m, 1 H) 7.5 (s, 2 H) 7.6 (m, 1 H) 7.8 (d, J=8.3 Hz, 1 H) 7.9 (m, 1 H).

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