Reaction #1121777

Reaction equation

2-amino-3-bromo-5-phenylpyrazine

2-Amino-3-Bromo-5-phenylpyrazine

cyclopentanethiol

sodium hydride

→

title compound 18n

Yield 67.6%

2-Amino-5-phenyl-3-cyclopentylthiopyrazine

Yield 67.6%

Solvents

acetonitrile

Conditions

Workup

1. 1
   Temperaturecooled
2. 2
   Otherquenched with water
3. 3
   workup.ADDITIONThen EtOAc was added
4. 4
   Filtrationfiltered
5. 5
   Otherthe solvent removed under reduced pressure
6. 6
   Otherto get a crude that
7. 7
   Otherwas purified by flash chromatography

Procedure

To a solution of cyclopentanethiol (0.18 g, 1.80 mmol) in dry acetonitrile (20 mL), sodium hydride (NaH) (0.04 g, 1.80 mmol) was added the resulting mixture was stirred for 15 min. After this time 2-amino-3-bromo-5-phenylpyrazine 17b (0.15 g, 0.6 mmol) was added and the mixture heated at 80° C. for 2 h, cooled and quenched with water. Then EtOAc was added and the organic layer was anidrified over Na2SO4, filtered and the solvent removed under reduced pressure to get a crude that was purified by flash chromatography using dichloromethane-EtOAc (9:1 v/v) as eluent, to obtain 0.11 g of the title compound 18n as a yellow solid (mp 92-94° C., 67% yield). 1H-NMR (CDCl3): 1.68-1.83 (m, 6H), 2.28-2.31 (m, 2H), 4.21-4.28 (m, 1H), 4.93 (br s, 2H), 7.32-7.35 (m, 1H), 7.41-7.45 (m, 2H), 7.91-7.93 (m, 2H), 8.20 (s, 1H). MS (ESI): m/z 272 (Mile).

Source