反应详情

To a solution of (R)-tert-butyl 4-(7-acetoxy-5-methyl-6,7-dihydro-5H-cyclopenta[d]pyrimidin-4-yl)piperazine-1-carboxylate (1.16 g, 3.08 mmol) in 12 mL THF was added 3M LiOH (2.57 mL, 7.70 mmol) and 3 mL H2O. The reaction mixture was stirred at room temperature for 15 hours, after which H2O was added, and the mixture was extracted with 3×75 mL EtOAc. The combined extracts were dried (Na2SO4), filtered, and concentrated in vacuo. The crude was purified on silica gel (Biotage 40S) first with 1:1 to 1:6 DCM:EtOAC gradient, followed by 20:1 DCM:MeOH to give (R)-tert-butyl 4-(7-hydroxy-5-methyl-6,7-dihydro-5H-cyclopenta[d]pyrimidin-4-yl)piperazine-1-carboxylate (0.556 g, 54.0% yield) as a 1:1 mixture of diastereomers as a brown foam. MS (APCI+) m/z 335 [M+H]+.

1. extractionthe mixture was extracted with 3×75 mL EtOAc
2. dry with materialThe combined extracts were dried (Na2SO4)
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. customThe crude was purified on silica gel (Biotage 40S) first with 1:1 to 1:6 DCM