Reaktion #1541007

Reaktionsgleichung

dimethyl 4-benzyloxy-1H-pyrazole-3,5-dicarboxylate

bromo(phenyl)acetonitrile

Cs2CO3

→

title product

Dimethyl 4-benzyloxy-1-[cyano(phenyl)methyl]-1H-pyrazole-3,5-dicarboxylate

Lösungsmittel

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was removed in vacuo
2. 2
   Sonstigethe residue was partitioned between EtOAc and water
3. 3
   ExtraktionThe aqueous layer was extracted with EtOAc several times
4. 4
   Trocknenthe combined organic layers were dried over Na2SO4
5. 5
   Einengenconcentrated in vacuo
6. 6
   SonstigeThe resulting residue was purified by flash column chromatography on silica gel using
7. 7
   Waschena gradient elution of 0-20% EtOAc/hexanes
8. 8
   SonstigeCollection and concentration of the appropriate fractions

Vorschrift

A solution of dimethyl 4-benzyloxy-1H-pyrazole-3,5-dicarboxylate (1.0 g, 3.45 mmol) and bromo(phenyl)acetonitrile (810 mg, 4.13 mmol) in anhydrous DMF was treated with Cs2CO3 (1.46 g, 4.48 mmol) and stirred at room temperature for 3 days. The solvent was removed in vacuo and the residue was partitioned between EtOAc and water. The aqueous layer was extracted with EtOAc several times, and the combined organic layers were dried over Na2SO4 and concentrated in vacuo. The resulting residue was purified by flash column chromatography on silica gel using a gradient elution of 0-20% EtOAc/hexanes. Collection and concentration of the appropriate fractions yielded the title product as a yellow oil. 1H NMR (400 MHz, d6-DMSO) δ 7.70 (s, 1H), 7.50-7.45 (m, 3H), 7.43-7.29 (m, 7H), 5.08 (s, 2H), 3.86 (s, 3H), 3.81 (s, 3H); ES MS (M+1)=406.

Quelle