反应详情

3-Bromo-5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyrazine (prepared by standard BOC deprotection of tert-Butyl 3-bromo-5,6-dihydro-1,2,4-triazolo[4,3-a]pyrazine-7(8H)-carboxylate, CAS [723286-80-4], commercially available e.g. from Allichem, Ark Pharm or Bepharm) (0.6 mmol) and diethylaminomethyl polystyrene (0.6 g, 1.92 mmol) were slurried in Dichloromethane (DCM) (7 mL) under argon. 2-Chloro-3-(trifluoromethyl)benzoyl chloride (0.16 g, 0.66 mmol, commercially available e.g. from Apollo Scientific or Shanghai FWD Chemicals) was added to the reaction. The mixture was stirred for 4 hours. The resin was filtered, washed with Dichloromethane (50 mL) and concentrated in vacuo to afford crude product. The crude product was purified by using mass-directed automated (preparative) HPLC (MDAP). The fractions containing the products were evaporated, diluted with diethyl ether and treated with 1 mL of HCl in diethyl ether; the solutions were stirred for 30 min. and solvent evaporated to give 3-bromo-7-{[2-chloro-3-(trifluoromethyl)phenyl]carbonyl}-5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyrazine (0.268 g). LC/MS [M+H]+=410.9, retention time=2.07 minutes (5 minute method).

1. filtrationThe resin was filtered
2. washwashed with Dichloromethane (50 mL)
3. concentrationconcentrated in vacuo
4. customto afford crude product
5. customThe crude product was purified
6. additionThe fractions containing the products
7. customwere evaporated
8. additiondiluted with diethyl ether
9. additiontreated with 1 mL of HCl in diethyl ether
10. stirringthe solutions were stirred for 30 min.
11. customsolvent evaporated