Triphenylphosphine → N-[2-[N-ethyl-N-[2-(2-nitropyridin-3-yloxy)ethyl]amino]ethyl]phthalimide

Participants

Reaction Steps

To a solution of compound 3 (11.3 g, 43.1 mmol) in anhydrous tetrahydrofuran (400 mL) were added successively, under argon, triphenylphosphine (11.3 g, 43.1 mmol), 2-nitro-3-hydroxypyridine (6.02 g, 43.0 mmol) and dropwise diisopropyl azodicarboxylate (8.70 mL, 44.2 mmol). The mixture was stirred at room temperature for 60 h and the solvent was evaporated under vacuum. Unreacted 2-nitro-3-hydroxypyridine was removed by chromatography (Al2O3., AcOEt/cyclohexane, 9/1, v/v). The residue containing the desired product was dissolved in dichloromethane (200 mL) and pentane (600 mL) was added. The mixture was stirred at room temperature for 5 min and the precipitate was filtered and dried under vacuum to give compound 58 (12.7 g, 33.0 mmol) as a yellow solid. Yield 77%; Rf (Al2O3, AcOEt/cyclohexane, 9/1, v/v) 0.76; mp 124-126° C.; IR (KBr) ν 1274, 1397, 1536, 1702, 1767, 2830 cm−1; 1H NMR (200 MHz, CDCl3) δ 0.96 (t, 3H, J=7.1 Hz), 2.63 (q, 2H, J=7.1 Hz), 2.81 (t, 2H, J=6.4 Hz), 2.94 (t, 2H, J=5.8 Hz), 3.76 (t, 2H, J=6.4 Hz), 4.10 (t, 2H, J=5.8 Hz), 7.50 (m, 2H), 7.60 (m, 2H), 7.75 (m, 2H), 8.05 (dd, 1H, J=2.5, 3.4 Hz); ESI-MS m/z 385.0 [M+H]+.

Provenance & Evidence