... The Journal of Organic ... mixture was stirred at room temperature for 15 h. The mixture was extracted with dichloromethane (3 × 15 mL), and the combined organic phases were ... 1595, 1293; NMR δ H (400 MHz; CDCl 3 ) 8.45 (1H, br s, NH), 4.41 (1H, s, CH), 2.89 (3H, d, J = 4.8 Hz ...