Benzyl Bromide → Methyl 1-benzyl-1H-pyrrole-2-carboxylate

Participants

Reaction Steps

To a cooled (0° C.) solution of methyl-2-pyrrole carboxylate (8.00 g, 63.9 mmol) in DMF (320 mL) was added NaH (60% by weight 5.10 g, 128 mmol). After 20 min, benzylbromide (11.4 mL, 95.9 mmol) was added and the reaction was warmed to rt. Stirring was continued for 2 h before quenching with saturated aq NH4Cl (0.5 L). The mixture was extracted 3× with EtOAc and the combined organic layers were washed with H2O (3×) and brine, dried over MgSO4, filtered and concentrated in vacuo to give a yellow oil. The crude product was chromatographed over silica gel (0 to 10% EtOAc in heptane over 25 min) to give methyl 1-benzyl-1H-pyrrole-2-carboxylate as a colorless oil (7.75 g, 56%). Rf=0.48 (25:75 heptane/EtOAc); 1H NMR (400 MHz, CDCl3) δ (ppm) 7.28-7.34 (m, 2H) 7.23-7.27 (m, 1H) 7.09-7.13 (m, 2H) 7.01 (dd, J=4.0, 1.8 Hz, 1H) 6.88-6.91 (m, 1H) 6.19 (dd, J=4.0, 2.6 Hz, 1H) 5.57 (s, 2H).

Provenance & Evidence