反应详情

4-(4-Morpholin-4-ylmethyl-benzoyl)-piperazine-1-carboxylic acid tert-butyl ester. A solution of 4-(4-formyl-benzoyl)-piperazine-1-carboxylic acid tert -butyl ester (2.06 g) in methanol (100 mL) was treated with morpholine (4 mL) and NaB(OAc)3H (6.98 g, in portions over 1 h). After 3 h, the mixture was diluted with satd. aq. NaHCO3 and extracted with CH2Cl2. The organic layer was dried (Na2SO4) and concentrated. The residue was purified by column chromatography (SiO2) to give the title compound (1.22 g, 48%). MS (ESI): mass calcd. for C21H31N3O4, 389.23; m/z found, 390.4 [M+H]+. 1H NMR (CDCl3): 7.39-7.33 (m, 4H), 3.75-3.66 (m, 6H), 3.50 (s, 2H), 3.51-3.33 (m, 6H), 2.45-2.41 (m, 4H), 1.46 (s, 9H).

1. additionthe mixture was diluted with satd
2. extractionaq. NaHCO3 and extracted with CH2Cl2
3. dry with materialThe organic layer was dried (Na2SO4)
4. concentrationconcentrated
5. customThe residue was purified by column chromatography (SiO2)