Reaktion #57674

Reaktionsgleichung

5-bromo-4-methoxy-3-methyl-benzofuran-2-carboxylic acid

oxalyl chloride

(S)-2-(4′-amino-biphenyl-4-sulfonylamino)-3-methyl-butyric acid methyl ester

→

(S)-2-{4′-[(5-bromo-4-methoxy-3-methyl-benzofuran-2-carbonyl)-amino]-biphenyl-4-sulfonylamino}-3-methyl-butyric acid methyl ester

Ausbeute 23.0%

Lösungsmittel

dichloromethane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture was refluxed for 2 h
2. 2
   Sonstigethe excess oxalyl chloride was removed by vacuum
3. 3
   workup.DISSOLUTIONThe residue was dissolved in 0.5 mL of dichloromethane
4. 4
   Waschenwas washed with 2N HCl, and water
5. 5
   SonstigeRemoval of the solvent from the organic solution

Vorschrift

To 40 mg (0.14 mmol) of 5-bromo-4-methoxy-3-methyl-benzofuran-2-carboxylic acid was added 0.5 mL of oxalyl chloride and the mixture was refluxed for 2 h, then the excess oxalyl chloride was removed by vacuum. The residue was dissolved in 0.5 mL of dichloromethane and was added to a mixture of 92 mg (0.25 mmol) of (S)-2-(4′-amino-biphenyl-4-sulfonylamino)-3-methyl-butyric acid methyl ester, 34 mg (0.28 mmol) of 4-(dimethylamino)pyridine and 1 mL of dichloromethane in an ice/water bath. The mixture was stirred at 0° C. for overnight. The mixture was diluted with dichloromethane and was washed with 2N HCl, and water. Removal of the solvent from the organic solution gave 20 mg (23% yield) of (S)-2-{4′-[(5-bromo-4-methoxy-3-methyl-benzofuran-2-carbonyl)-amino]-biphenyl-4-sulfonylamino}-3-methyl-butyric acid methyl ester as an off-white solid.

Quelle