Reaction #73385

Reaction equation

4-[1-(3-trifluoromethyl-phenylcarbamoyl)-1H-indol-5-yloxy]-pyridine-2-carboxylic acid

Et3N

oxalyl chloride

tert-butyl carbazate

→

N′-{4-[1-(3-Trifluoromethyl-phenylcarbamoyl)-1H-indol-5-yloxy]-pyridine-2-carbonyl}-hydrazinecarboxylic acid tert-butyl ester

Solvents

DCM

DCM

Conditions

Workup

1. 1
   Washwashed with pH 7 buffer (15 mL)
2. 2
   DryingThe organic layer is then dried (Na2SO4)
3. 3
   Filtrationfiltered
4. 4
   Concentrationconcentrated
5. 5
   OtherThe residue is separated via FCC (30-60% EtOAc/heptane)

Procedure

To a solution of acid 4-[1-(3-trifluoromethyl-phenylcarbamoyl)-1H-indol-5-yloxy]-pyridine-2-carboxylic acid, Example 28-A, (0.100 g, 0.226 mmol) in DCM (5 mL) is added Et3N (0.09 mL), DMF (2 drops) and oxalyl chloride (0.17 mL, 0.340 mmol, 2.0 M DCM). After 0.5 h tert-butyl carbazate is added (0.045 g, 0.340 mmol). After 1.5 h the solution is diluted with DCM (10 mL) and then washed with pH 7 buffer (15 mL). The organic layer is then dried (Na2SO4), filtered, and concentrated. The residue is separated via FCC (30-60% EtOAc/heptane) to give N′-{4-[1-(3-Trifluoromethyl-phenylcarbamoyl)-1H-indol-5-yloxy]-pyridine-2-carbonyl}-hydrazinecarboxylic acid tert-butyl ester. MS (ESI) m/z 484.3 (M+1).

Source