反应详情

温度

0 °C

Add titanium isopropoxide (860 mg, 3.03 mmol) to a solution of ethyl 3-(dibenzylamino)propanoate (9.0 g, 30.3 mmol) in ethyl ether, cool to 0° C., add ethyl magnesium bromide (3M in Et2O, 30.3 mL) drop-wise over 1 h, maintaining the temperature at ˜0-4° C., allow to warm to RT and stir overnight. Cool to 0° C., add satd. NH4Cl, stir at RT for 15 minutes, make basic with satd. NaHCO3 and extract with EtOAc (2×). Wash the combined organics with brine, dry over MgSO4, concentrate and purify via silica gel chromatography to give the title compound (7.5 g, 88%) as a pale yellow oil. 1H NMR (400 MHz, CDCl3): δ 7.20-7.15 (m, 8H), 7.12-7.07 (m, 2H), 3.45 (s, 4H), 2.61-2.59 (m, 2H), 1.57 (t, J=5.6 Hz, 2H), 0.36-0.33 (m, 2H), 0.30-0.17 (m, 2H).

1. temperaturemaintaining the temperature at ˜0-4° C.
2. temperatureto warm to RT
3. temperatureCool to 0° C.
4. additionadd
5. extractionNaHCO3 and extract with EtOAc (2×)
6. washWash the combined organics with brine
7. dry with materialdry over MgSO4
8. concentrationconcentrate
9. custompurify via silica gel chromatography