反応 #520783

反応方程式

5-bromopyridine-3-carboxylic acid methyl ester

LiCl

3,4-dichlorophenyl boronic acid

K2CO3

→

title compound

収率 95.0%

5-(3,4-Dichloro-phenyl)-nicotinic Acid Methyl Ester

収率 95.0%

溶媒

H2O

toluene

反応条件

後処理

1. 1
   温度the stirred mixture heated under an argon atmosphere at 100° C. for 23 h
2. 2
   温度After cooling
3. 3
   その他the aqueous phase separated
4. 4
   抽出extracted with AcOEt
5. 5
   洗浄The combined organic extracts were washed with saturated NaCl solution
6. 6
   乾燥dried with Na2SO4
7. 7
   ろ過filtered
8. 8
   その他the solvent evaporated
9. 9
   その他the product dried under high vacuum at 50° C. for 2 h

実験手順

To a solution of 5-bromopyridine-3-carboxylic acid methyl ester (2 g, 9.3 mmol) in toluene (50 ml) was added tetrakis-(triphenylphosphine)-palladium (0) (320 mg, 0.28 mmol) followed by LiCl (785 mg, 18.5 mmol) and the mixture was stirred 30 min at 20° C. Then 3,4-dichlorophenyl boronic acid (50 wt % in THF/H2O 9:1) (3.7 g, 3.3 ml, 9.7 mmol) and 2N aq. K2CO3 (11.3 ml, 2.5 eq.) were added and the stirred mixture heated under an argon atmosphere at 100° C. for 23 h. After cooling, H2O was added (25 ml) and the aqueous phase separated and extracted with AcOEt. The combined organic extracts were washed with saturated NaCl solution, dried with Na2SO4, filtered and the solvent evaporated and the product dried under high vacuum at 50° C. for 2 h to afford the title compound (2.48g, 95%) as a beige solid. MS: m/e=281.0 (M+H+).

出典