Acetic Acid → N-benzyl4-(N-Boc-2-aminoethyl)aniline

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-(N-Boc-2-aminoethyl)aniline 28 (10 g, 42.34 mmole), benzaldehyde (4.52 mL, 44.47 mmole), and molecular sieves 4A (10 g) in toluene (100 mL) was refluxed at 95° C. for 15 h. The reaction mixture was filtered and the filtrate was concentrated in vacuo to give a colorless oil. The oil was dissolved in MeOH (150 mL) and AcOH (0.5 mL) and NaCNBH3 (2.79 g, 44.4 mmole) were added. The reaction mixture was stirred at 0° C. for 1 h and at rt for 2 h and then concentrated in vacuo to give a pale yellow oily residue. Purification by flash silica column chromatography: 1/1 hexane/EtOAc gave N-benzyl-4-(N-Boc-2-aminoethyl)aniline 41 as colorless oil (11.5 g, 83%). Rf=0.75 in 1/1 hexane/EtOAc. H1-NMR (CD3OD, 299.96 MHz): δ (ppm) 7.38-7.2 (m, 5H), 6.87-6.84 (d, 2H), 6.58-6.55 (d, 2H), 4.27 (s, 2H), 3.2-3.15 (m, 2H), 2.6-2.56 (t, 2H), 1.41 (s, 9H); ESMS (C20H26N2O2): calcd. 326.4, obsd. 328 [M+H]+.

Provenance & Evidence