反応 #2439925

反応方程式

p-fluorphenylboronic acid

3-bromo-5-hydroxymethyl-pyridine

Na2CO3

→

3-(p-fluorophenyl)-5-hydroxymethyl-pyridine

収率 84.4%

溶媒

toluene

反応条件

後処理

1. 1
   その他the biphasic reaction mixture
2. 2
   温度was cooled
3. 3
   その他the organic layer was collected
4. 4
   洗浄washed with saturated NaCl
5. 5
   洗浄The aqueous layer was washed with EtOAc
6. 6
   その他the combined organic layers were dried on Na2SO4
7. 7
   その他The drying agent was removed by filtration
8. 8
   その他the solvent was evaporated in vacuo
9. 9
   その他to give a dark oil which
10. 10
    その他was purified by flash chromatography on silica gel (eluent: CH2Cl2/MeOH/NH4OH, 95/4.5/0.5)

実験手順

To a solution of 3-bromo-5-hydroxymethyl-pyridine (3.3 g, 17.5 mmol) in toluene (35 ml) was added Pd(PPh3)4 (0.6 g, 0.52 mmol), an aqueous solution of Na2CO3 (17.5 ml of a 2M solution) and p-fluorphenylboronic acid (2.65 g, 19 mmol, dissolved in 8.5 ml EtOH). The mixture was heated at 80-90° C. for 1 hr and vigorously stirred. After the reaction was completed, the biphasic reaction mixture was cooled, the organic layer was collected and washed with saturated NaCl. The aqueous layer was washed with EtOAc and the combined organic layers were dried on Na2SO4. The drying agent was removed by filtration and the solvent was evaporated in vacuo to give a dark oil which was purified by flash chromatography on silica gel (eluent: CH2Cl2/MeOH/NH4OH, 95/4.5/0.5) and yielded 3-(p-fluorophenyl)-5-hydroxymethyl-pyridine (3.0 g, 84%). The product was converted into its monohydrochloride salt; the residue was dissolved in Et2O and treated with 16.5 eq of ethanolic HCl. The product 3-(p-fluorophenyl)-5-hydroxymethyl-pyridinium hydrochloride Q4-OH.HCl precipitated as a white solid which was collected by filtration and subsequent drying.

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