Reaction #2487466

Reaction equation

hydrochloric acid

1,1′-carbonyldiimidazole

1,8-diazabicyclo[5.4.0]undec-7-ene

6-(5-methoxy-2-phenylindol-1-ylmethyl)pyridine-2-carboxamidoxime

1,1′-carbonyldiimidazole

1,8-diazabicyclo[5.4.0]undec-7-ene

→

title compound

Yield 87.4%

3-[6-(5-Methoxy-2-phenylindol-1-ylmethyl)pyridin-2-yl]-4,5-dihydro-1,2,4-oxadiazol-5-one

Yield 87.4%

Solvents

tetrahydrofuran

Conditions

Workup

1. 1
   workup.STIRRINGby stirring at room temperature for 1 hour
2. 2
   Extractionfollowed by extraction with ethyl acetate
3. 3
   WashThe organic layer was washed with water and saturated brine
4. 4
   Dryingdried over anhydrous magnesium sulfate
5. 5
   Concentrationconcentrated under reduced pressure
6. 6
   OtherThe residue was recrystallized from ethanol

Procedure

To a solution of 6-(5-methoxy-2-phenylindol-1-ylmethyl)pyridine-2-carboxamidoxime (124 mg) in tetrahydrofuran (1.7 mL) were added 1,1′-carbonyldiimidazole (57 mg) and 1,8-diazabicyclo[5.4.0]undec-7-ene (53 μL). This mixture was stirred at room temperature for 2 hours. To the reaction mixture were added 1,1′-carbonyldiimidazole (27 mg) and 1,8-diazabicyclo[5.4.0]undec-7-ene (25 μL), followed by stirring at room temperature for 1 hour. To the reaction mixture was added 1 mol/L hydrochloric acid, followed by extraction with ethyl acetate. The organic layer was washed with water and saturated brine, dried over anhydrous magnesium sulfate, and then concentrated under reduced pressure. The residue was recrystallized from ethanol to obtain the title compound (116 mg). 1H-NMR (DMSO-d6) δ ppm: 3.78 (3H, s), 5.55 (2H, s), 6.55-6.70 (2H, m), 6.77 (1H, dd, J=2.4, 8.9 Hz), 7.15 (1H, d, J=2.4 Hz), 7.26 (1H, d, J=8.9 Hz), 7.35-7.55 (5H, m), 7.75-7.90 (2H, m), 13.07 (1H, br s).

Source