[F:1][C:2]1[CH:10]=[CH:9][C:8]([Cl:11])=[CH:7][C:3]=1[C:4]([NH2:6])=[NH:5].C([O:14][C:15]([CH:17]1[C:21](=O)[CH2:20][CH2:19][CH:18]1[CH3:23])=O)C>CCO>[Cl:11][C:8]1[CH:9]=[CH:10][C:2]([F:1])=[C:3]([C:4]2[N:6]=[C:15]([OH:14])[C:17]3[CH:18]([CH3:23])[CH2:19][CH2:20][C:21]=3[N:5]=2)[CH:7]=1To a solution of 2-fluoro-5-chlorobenzamidine (1.95 g, 11.27 mmol, 1.1 eq) in EtOH (20 ml) was added a solution of 2-methyl-5-oxo cyclopentanecarboxylic acid ethyl ester (prepared according to Wang, C.; Gu, X.; Yu, M. S.; Curran, D. P.: Tetrahedron, 1998, 29, 8355-8370; 1.60 g, 10.26 mmol, 1 eq) in ethanol (5 ml). The reaction mixture was heated to 80° C. overnight. The reaction mixture was cooled to rt and the solvent was removed in vacuo to give a crude residue which was purified by recrystallization from hot ethyl acetate to give 2-(5-chloro-2-fluorophenyl)-5-methyl-6,7-dihydro-5H-cyclopentapyrimidin-4-ol (1.0 g, 35%) as a white crystalline solid and the filtrate was further purified by flash column chromatography to give another 850 mg of 2-(5-chloro-2-fluorophenyl)-5-methyl-6,7-dihydro-5H-cyclopentapyrimidin-4-ol.
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