Reaction #71337

Reaction equation

8-(2,6-dichloro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid [1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazol-2-yl]-amide

HCl

Na2CO3

→

title compound

Yield 79.1%

8-(2,6-Dichloro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid (1H-imidazol-2-yl)-amide

Yield 79.1%

Solvents

EtOH

Conditions

Workup

1. 1
   Temperatureto cool to rt
2. 2
   Extractionextracted with DCM
3. 3
   WashThe combined organic phase was washed with H2O and brine
4. 4
   Dryingdried (Na2SO4)
5. 5
   Filtrationfiltered
6. 6
   Concentrationconcentrated
7. 7
   OtherThe residue was purified by silica gel column chromatography (DCM/MeOH/NH3aq, 94:5:1)

Procedure

A mixture of 8-(2,6-dichloro-3,5-dimethoxy-phenyl)-quinoxaline-5-carboxylic acid [1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazol-2-yl]-amide (Step 14.1) (0.527 g, 0.82 mmol), 5 N HCl (7 mL), and EtOH (4 mL) was stirred at 65° C. for 10 h. The reaction mixture was allowed to cool to rt, basified by addition of a saturated aqueous solution of Na2CO3, and extracted with DCM. The combined organic phase was washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH/NH3aq, 94:5:1) to afford 0.288 g of the title compound as a yellow solid: ESI-MS: 443.9/445.9 [M+H]+; tR=3.74 min (System 1); TLC: Rf=0.30 (DCM/MeOH/NH3aq, 94:5:1).

Source