Reaction Steps
Chiral resolution of cis-7-(2-Chloro-6-fluorophenyl)-5-(4-chlorophenyl)-4,5,6,7-tetrahydro-[1,2,4]triazolo[1,5-a]pyrimidine: Chiral resolution of 7-(2-Chloro-6-fluorophenyl)-5-(4-chlorophenyl)-4,5,6,7-tetrahydro[1,2,4]triazolo[1,5a]pyrimidine was carried out on the Waters 2695 HPLC instrument, equipped with CHIRALPAK® AD-RH column. Eluent system was: 30% A (H2O), 70% B (EtOH); flow rate=0.5 mL/min; λ=219 nm. The two enantiomers, 40a, (R,S)-7-(2-Chloro-6-fluoro-phenyl)-5-(4-chloro-phenyl)-4,5,6,7-tetrahydro-[1,2,4]triazolo[1,5-a]pyrimidine, and 40b, (S,R)-7-(2-Chloro-6-fluoro-phenyl)-5-(4-chloro-phenyl)-4,5,6,7-tetrahydro-[1,2,4]triazolo[1,5-a]pyrimidine were isolated by removal of the solvents from peaks eluted at 43.5 minutes and 57.8 minutes respectively. 40a, (R,S)-7-(2-Chloro-6-fluoro-phenyl)-5-(4-chloro-phenyl)-4,5,6,7-tetrahydro-[1,2,4]triazolo[1,5-a]pyrimidine: Rf=0.16 (EtOAc/Hexanes 33.3:66.7). MS: MH+=363. 1H NMR (500 MHz, DMSO-d6): δ 7.54-7.15 (m, 8H, CHar), 5.98-5.94 (m, 1H, CH), 4.82-4.78 (m, 1H, CH), 2.47-2.13 (m, 2H, CH2). HPLC: 99.8% (Method A, tR=3.67 min), CHIRALPAK® AD-RH column Rf=43.5 minutes. 40b, (S,R)-7-(2-Chloro-6-fluoro-phenyl)-5-(4-chloro-phenyl)-4,5,6,7-tetrahydro-[1,2,4]triazolo[1,5-a]pyrimidine: Rf=0.16 (EtOAc/Hexanes 33.3:66.7). MS: MH+=363. 1H NMR (500 MHz, DMSO-d6): δ 7.54-7.15 (m, 8H, CHar), 5.98-5.94 (m, 1H, CH), 4.82-4.78 (m, 1H, CH), 2.47-2.13 (m, 2H, CH2). HPLC: 99.8% (Method A, tR=3.67 min), CHIRALPAK® AD-RH column Rf=57.8 minutes.
