N-BOC-ethylenediamine → Tert-butyl 2-(2-tert-butoxybenzylamino)ethylcarbamate

Participants

Reaction Steps

N-Boc-ethylenediamine (2.6 g, 16 mmol) and 8 (2.9 g, 16 mmol) were added to 250 mL of CH3CN and the reaction mixture was refluxed under argon for 4 hr. After cooling down to room temperature, the solvent was removed and the residue was redissolved in MeOH. The solvent was then evaporated and NaBH4 (3 g, 16 mmol) was added and stirred overnight. The solvent was evaporated, followed by extraction with CH2Cl2. The CH2Cl2 extract was concentrated and purified by a silica gel column using 2% methanolic NH3 (7 M NH3 in methanol/98% CH2Cl2 as eluent to yield the desired product as a pale yellow oil (97%). 1H NMR (CDCl3) δ 7.204 (dd, 1H, Ar), 7.115 (ddd, 1H, Ar), 7.007 (dd, 1H, Ar), 6.930 (ddd, 1H, Ar), 3.718 (s, 2H, —CH2—), 3.175 (d, 2H, —CH2—), 2.638 (t, 2H, —CH2—), 1.402 (s, 9H, —C(CH3)3), 1.382 (s, 9H, —C(CH3)3). Mass Spect.=323.23 (M+H)+.

Provenance & Evidence