Reaktion #9241

Reaktionsgleichung

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

3-aminophenyl boric acid

sodium bicarbonate

boric acid

→

desired compound

Ausbeute 23.4%

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

Ausbeute 23.4%

Lösungsmittel

—

mixed solvent

DMF water

MeOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas purged with nitrogen gas
2. 2
   SonstigeIt was purged with nitrogen gas again
3. 3
   Einengenconcentrated
4. 4
   workup.DISSOLUTIONdissolved in methylene chloride
5. 5
   Waschenwashed with sodium bicarbonate solution
6. 6
   Trocknendried (MgSO4)
7. 7
   Sonstigeevaporated
8. 8
   Sonstigepurified by flash chromatography on SiO2 with MeOH and methylene chloride (1/50)

Vorschrift

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.

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