Tuesday, October 20, 2009

Organic Synthesis – N-phenylbenzamide Synthesis

Synthesis of N-phenylbenzamide or Benzanilide

N-Phenylbenzamide
Following the general procedure for anilide synthesis using aniline and benzoyl chloride, the reaction was performed on a 20.0 mmol scale for 4 h. To a stirred solution of aniline (1.0 eq.) in EtOAc, were added triethylamine (1.05 eq.) and acid chloride (1.05 eq.) at 0 °C. The reaction mixture was stirred at room temperature for 2-8 h after which it was extracted with EtOAc. The extract was washed with brine and dried over MgSO4. Concentration under reduced pressure and purification by flash column chromatography or recrystalization afforded pure anilide substrate.The title compound was isolated by recrystalization (EtOAc-hexane) as a white solid. (3.78 g, 96%). m.p. 159-160 °C (lit.4 m.p. 161-161.5 °C); 1H NMR (400 MHz, DMSO-d6) δ 10.28 (s, 1H), 7.98 (d, 2H, J = 8.0 Hz), 7.82 (d, 2H, J = 8.4 Hz), 7.60-7.49 (m, 3H), 7.39-7.32 (m, 2H), 7.10 (t, 1H, J = 7.6 Hz); 13C NMR (100 MHz, DMSO-d6) δ 180.2, 153.9, 149.7, 146.2, 143.2, 143.0, 142.3, 138.3, 135.0; MS (EI): m/z 197 (M+).
References: Zhang, Z.; Yu, Y.; Liebeskind, L. S. Org. Lett. 2008, 10, 3005.
JOC , 2009,4272-4277.