Acetic Acid → methyl 4-[2-(N-benzyloxycarbonyl-N-methylamino)ethylamino]benzoate

Participants

Reaction Steps

A stirred solution of N-benzyloxycarbonyl-N-methylaminoacetaldehyde (1.77 g, 1.1 mmol) in toluene (3 mL) was added methyl-4-aminobenzoate (1.29 g, 8.5 mmol), and the mixture was stirred for 1 hr at room temp. The reaction mixture was evaporated under a reduced pressure and the residue was dissolved into MeCN (15 mL). To the solution was added AcOH (2.44 mL, 43 mmol) and NaBH3CN (2.67 g, 43 mmol), and the resulting mixture was stirred for 15 hr at room temp. The reaction was quenched by the addition of sat. NaHCO3. The mixture was extracted with EtOAc, washed with brine, dried over MgSO4, and evaporated. The residue was chromatographed on silica-gel with n-hexane: EtOAc (7:3, v/v) as eluent to give 1.26 g (43%) methyl 4-[2-(N-benzyloxy carbonyl-N-methylamino)ethylamino]benzoate as a colorless oil. 1H-NMR (CDCl3, 400 MHz) δ2.96 (s, 3H), 3.32 (br m, 2H), 3.50-3.60 (m, 2H), 3.82 (s, 3H), 5.15 (each d, 2H, J=14.6 Hz), 6.35 and 6.58 (m, total 2H), 7.36 (s, 5H), 7.76 and 7.84 (m, total 2H); MS (FAB) m/z 342 (M++1).

Provenance & Evidence