Phthalimide → tert-butyl 4-[(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)acetyl]piperazine-1-carboxylate

Participants

Reaction Steps

Phthalimide (33 mg, 0.23 mmol) was treated with tert-butyl 4-(2-chloroacetyl)piperazine-1-carboxylate (80.5 mg, 0.32 mmol), tetrabutylammonium iodide (TBAI, 84 mg, 2.3 mmol), diisopropylethylamine (DIEA, 0.20 mg, 1.14 mmol) in anhydrous CH2Cl2 (10 mL) for 24 h at 40° C. The mixture was partitioned between CH2Cl2 and water. The organic phase was separated, dried over MgSO4, filtered, concentrated, and purified by flash chromatography on a silica gel column with elution of EtOAc/hexane (1:1) to give the title compound (57.1 mg, 67% yield). C19H23N3O5; white solid; TLC (EtOAc/hexane=1:1) Rf=0.2; 1H NMR (400 MHz, CDCl3) δ 7.85-7.87 (2H, m), 7.70-7.72 (2H, m), 4.49 (2H, s), 3.51-3.57 (6H, m), 3.44 (2H, d, J=5.2 Hz), 1.46 (9H, d, J=4.8 Hz).

Provenance & Evidence