反应详情

To a stirred solution of ((R)-tert-butyl 2-(3,3-dimethylureido)-2-phenylacetate (0.86 g, 3.10 mmol) in CH2Cl2 (250 mL) was added TFA (15 mL) dropwise and the resulting solution was stirred at rt for 3 h. The desired compound was then precipitated out of solution with a mixture of EtOAC:Hexanes (5:20), filtered off and dried under reduced pressure. (R)-2-(3,3-dimethylureido)-2-phenylacetic acid was isolated as a white solid (0.59 g, 86%) and used without further purification. 1H NMR (500 MHz, DMSO-d6) δ ppm 2.82 (s, 6H) 5.22 (d, J=7.32 Hz, 1H) 6.58 (d, J=7.32 Hz, 1H) 7.28 (t, J=7.17 Hz, 1H) 7.33 (t, J=7.32 Hz, 2H) 7.38-7.43 (m, 2H) 12.65 (s, 1H). LCMS: Anal. Calcd. for C11H14N2O3: 222.24. found: 223.21 (M+H)+. HPLC XTERRA C-18 3.0×50 mm, 0 to 100% B over 2 minutes, 1 minutes hold time, A=90% water, 10% methanol, 0.2% H3PO4, B=10% water, 90% methanol, 0.2% H3PO4, RT=0.75 min, 93% homogeneity index.

1. customThe desired compound was then precipitated out of solution with a mixture of EtOAC
2. filtrationHexanes (5:20), filtered off
3. customdried under reduced pressure