反応 #9241

反応方程式

1-(6-bromo-2-benzothiazolyl)-3-ethylurea

3-aminophenyl boric acid

sodium bicarbonate

boric acid

→

desired compound

収率 23.4%

1-(6-(3-Aminophenyl)-2-benzothiazolyl)-3-ethylurea

収率 23.4%

溶媒

—

mixed solvent

DMF water

MeOH

反応条件

後処理

1. 1
   その他was purged with nitrogen gas
2. 2
   その他It was purged with nitrogen gas again
3. 3
   濃縮concentrated
4. 4
   workup.DISSOLUTIONdissolved in methylene chloride
5. 5
   洗浄washed with sodium bicarbonate solution
6. 6
   乾燥dried (MgSO4)
7. 7
   その他evaporated
8. 8
   その他purified by flash chromatography on SiO2 with MeOH and methylene chloride (1/50)

実験手順

A suspension of 1-(6-bromo-2-benzothiazolyl)-3-ethylurea (0.300 g, 1.00 mmol), 3-aminophenyl boric acid (0.237 g, 1.50 mmol, 1.5 eq), and sodium bicarbonate (0.210 g, 2.50 mmol, 2.5 eq) in 8 mL of mixed solvent DMF/water (5/1) was purged with nitrogen gas. To the mixture, the catalyst Pd(PPh3)4 (0.058 g, 0.05 mmol, 0.05 eq) was added. It was purged with nitrogen gas again, and was heated at about 100° C. in a sealed tube for about 48 hours. More Pd(PPh3)4 (0.025 g, 0.02 mmol, 0.02 eq) and more boric acid (0.080 g, 0.50 mmol, 0.50 eq) were added after the first 24 hours. The mixture was taken up in MeOH, concentrated, dissolved in methylene chloride, washed with sodium bicarbonate solution, dried (MgSO4), evaporated, and purified by flash chromatography on SiO2 with MeOH and methylene chloride (1/50) to give the desired compound 0.073 g (23%). LC/MS 313.2 (M+1); LC retention time 2.11 min.

出典