Reaktion #430276

Reaktionsgleichung

HCl

benzyl bromide

1H-Indazole-3-carboxylic acid

K2CO3

→

title compound

1-Benzyl-1H-indazole-3-carboxylic acid benzyl ester

Lösungsmittel

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthen heated at 60° C. for 16 h
2. 2
   TemperaturThe reaction is cooled to RT
3. 3
   Extraktionextracted with EtOAc (2×100 mL)
4. 4
   WaschenThe organic layers are washed with H2O (2×100 mL)
5. 5
   Trocknendried (MgSO4)
6. 6
   Sonstigethe solvent removed in vacuo
7. 7
   SonstigePurification of the crude material by silica gel flash column chromatography
8. 8
   Waschena gradient elution of hexane/EtOAc 20/1 to 2/1

Vorschrift

To a stirring solution of 750 mg (4.62 mmol) of 1H-Indazole-3-carboxylic acid (Snyder, H. R.; Thompson, C. B.; Hinman, R. L. J. Am. Chem. Soc. 1952, 74, 2009) in 20 mL of DMF is added 1.92 g (13.86 mmol, 3.0 equiv) of K2CO3, followed by 1.43 mL of benzyl bromide. The reaction mixture is stirred 15 min at RT then heated at 60° C. for 16 h. The reaction is cooled to RT, poured into 100 mL 1N HCl, and extracted with EtOAc (2×100 mL). The organic layers are washed with H2O (2×100 mL), dried (MgSO4), and the solvent removed in vacuo. Purification of the crude material by silica gel flash column chromatography using a gradient elution of hexane/EtOAc 20/1 to 2/1 afforded 735 mg of the title compound as a yellow oil which later solidified: 1H NMR (CDCl3, 300 MHz) δ8.20 (d, 1H), 7.55 (d, 2H), 7.40-7.18 (m, 11H), 5.70 (s, 2H), 5.57 (s, 2H); Rf =0.15 in hexane/EtOAc 10/1.

Quelle