反应详情

A solution of diethyl 2-{[(5-iodo-6-methyl-2-pyridinyl)amino]methylene}malonate Prep 3(1.09 g) in 20 mL diphenyl ether is heated at 250° C. for 2 h with removal of ethanol via a Dean-Stark trap. The reaction is cooled to room temperature. Hexanes (15 mL) are added and the solid is filtered, washed thoroughly with hexanes, and dried. The crude solid is dissolved in CH2Cl2/MeOH and adsorbed onto silica. Purification by chromatography (eluent CH2Cl2 (1L), 1% MeOH/CH2Cl2 (1L), 2% MeOH/CH2Cl2 (2L)) affords the product as a yellow-green solid (0.50 g, 52%). Physical characteristics are as follows: m.p. 275-277° C. (dec.); 1H NMR (300 MHz, DMSO-d6) δ 12.80, 8.72, 8.47, 4.21, 2.74, 1.27; IR (drift) 2981, 1718, 1606, 1524, 1407, 1376, 1356, 1319, 1291, 1244, 1192, 1185, 1109, 809, 623 cm−1; MS (ESI) m/z 358.9 (M+H)+, 356.9 (M−H)−; Anal. Calcd for C12H11IN2O3: C, 40.24; H, 3.10; N, 7.82; Found: C, 40.15; H, 3.05; N, 7.81.

1. filtrationthe solid is filtered
2. washwashed thoroughly with hexanes
3. customdried
4. dissolutionThe crude solid is dissolved in CH2Cl2/MeOH
5. customPurification by chromatography (eluent CH2Cl2 (1L), 1% MeOH/CH2Cl2 (1L), 2% MeOH/CH2Cl2 (2L))