Reaktion #47211

Reaktionsgleichung

5-tert-butyl-3-nitro-1H-pyrrole-2-carboxylic acid

PCl5

3,3-dimethylpiperazin-2-one

DIEA

→

4-(2-tert-butyl-4-nitro-1H-pyrrole-5-carbonyl)-3,3-dimethylpiperazin-2-one

Ausbeute 53.1%

Lösungsmittel

dichloromethane

dichloromethane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGstirred at room temperature for 5 minutes
2. 2
   Waschenwashed sequentially with 1N aqueous HCl, saturated sodium bicarbonate
3. 3
   Sonstigedried
4. 4
   Sonstigethe solvent removed under vacuum
5. 5
   SonstigeThe crude product was purified by chromatographic column (silica gel, dichloromethane:methanol, 95:5)

Vorschrift

The previously prepared 5-tert-butyl-3-nitro-1H-pyrrole-2-carboxylic acid (0.203 g, 1.11 mmol) and PCl5 (0.232 g, 1.11 mmol) were dissolved in dichloromethane (4 mL) and stirred at room temperature for 5 minutes. The resulting solution was added in one portion to a solution of 3,3-dimethylpiperazin-2-one (0.214 g, 1.67 mmol) and DIEA (0.288 g, 2.23 mmol) in dichloromethane (3 mL) and stirred at room temperature for 5 minutes. The reaction mixture was diluted with dichloromethane and washed sequentially with 1N aqueous HCl, saturated sodium bicarbonate, dried and the solvent removed under vacuum. The crude product was purified by chromatographic column (silica gel, dichloromethane:methanol, 95:5) to afford 0.190 g of expected 4-(2-tert-butyl-4-nitro-1H-pyrrole-5-carbonyl)-3,3-dimethylpiperazin-2-one.

Quelle