Reaktion #74159

Reaktionsgleichung

4-iodo-1-(4-methoxybenzyl)-3-(3-nitrophenyl)-1H-pyrazole

4,4,5,5-tetramethyl-1,3,2-dioxaborolane

S-Phos

triethylamine

→

title compound

Ausbeute 80.0%

1-(4-methoxybenzyl)-3-(3-nitrophenyl)-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole

Ausbeute 80.0%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeirradiation in a sealed vial at 90° C. for 30 minutes
2. 2
   FiltrationThe mixture was then filtered through a celite pad
3. 3
   Sonstigethe filtrate evaporated in vacuo
4. 4
   Waschenwashed with water
5. 5
   Trocknenthe organic layer dried over sodium sulphate
6. 6
   Sonstigeevaporated again
7. 7
   SonstigeThe crude was finally purified by flash-chromatography on a silica gel column (CH2Cl2-CH3COCH3 1%)

Vorschrift

1 g (2.3 mmol) of 4-iodo-1-(4-methoxybenzyl)-3-(3-nitrophenyl)-1H-pyrazole (prepared as described in Example 27) was dissolved in 20 ml of dry toluene and 3.18 ml of 4,4,5,5-tetramethyl-1,3,2-dioxaborolane (23 mmol), 20 mg (0.08 mmol) of palladium(II) chloride diacetonitrile complex, 80 mg (0.005 mmol) of S-Phos (2-dicyclohexylphosphino-2′,6′-dimethoxy-1,1′-biphenyl) and 774 μl (5.7 mmol) of triethylamine were added successively. The reaction mixture was submitted to microwave irradiation in a sealed vial at 90° C. for 30 minutes. The mixture was then filtered through a celite pad and the filtrate evaporated in vacuo. The residue was taken up with dichloromethane and washed with water and the organic layer dried over sodium sulphate and evaporated again. The crude was finally purified by flash-chromatography on a silica gel column (CH2Cl2-CH3COCH3 1%), affording 800 mg (80%) of the title compound, crystallized from diethylether.

Quelle