Oxidation of organic compounds

Electron-Deficient Heteroarenium Salts: An Organocatalytic Tool for Activation of Hydrogen Peroxide in Oxidations

“…The solid was dissolved in dioxane (30 mL), and aqueous ammonia (75 mL) was added. After 30 min, the white precipitate was collected by filtration, washed with water, and dried in vacuo to give 18g (1.72 g, 87%) as a white solid: mp 314–316 °C (lit . mp 300 °C); 1 H NMR (500 MHz, DMSO- d 6 ) δ 9.05 (s, 1H), 8.37 (dd, J = 8.1, 2.2 Hz, 1H), 8.29 (s, 1H), 8.22 (s, 1H), 8.10 (d, J = 8.1 Hz, 1H), 7.75 (s, 1H), 7.73 (s, 1H); 13 C NMR (126 MHz, DMSO- d 6 ) δ 165.8, 165.4, 152.1, 147.7, 136.7, 131.7, 121.6; HRMS-ESI ( m / z ) [M + H] + calcd for C 7 H 8 N 3 O 2 166.06110, found 166.06094.…”

“…The organic layers were combined, dried with sodium sulfate, and concentrated in vacuo. The crude product was purified by recrystallization (water) to give 18h (550 mg, 64%) as a white crystalline solid: mp 108–110 °C (lit . mp 112–113 °C; 1 H NMR (300 MHz, chloroform- d ) δ 9.00–8.97 (m, 1H), 8.15 (dd, J = 8.1, 2.1 Hz, 1H), 7.85 (d, J = 8.1 Hz, 1H); 13 C NMR (126 MHz, chloroform- d ) δ 152.2, 140.6, 136.6, 128.2, 115.8, 115.0, 113.1; HRMS-ESI ( m / z ) [M] − calcd for C 7 H 3 N 3 129.03215, found 129.03262.…”

“…The organic layers were combined, dried with sodium 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 sulfate and concentrated in vacuo. The crude product was purrified by recrystallization (water) to give 18h (550 mg, 64 %) as a white crystalline solid; mp 108-110 °C (ref 61 Pyridine-2,6-dicarboxamide 56 (18i):…”

“…After 30 min, the white precipitate was collected by filtration, washed with water, and dried in vacuo to give 18g (1.72 g, 87%) as a white solid: mp 314−316 °C (lit. 61 Pyridine-2,5-dicarbonitrile 62 (18h). Pyridine-2,5-dicarboxamide (18g) (1.1 g, 6.7 mmol) was dissolved in N,N-dimethylformamide (70 mL), and phosphoryl trichloride (3.7 mL, 40 mmol) was added.…”

“…The crude product was purified by recrystallization (water) to give 18h (550 mg, 64%) as a white crystalline solid: mp 108−110 °C (lit. 61 Pyridine-2,6-dicarboxamide 56 (18i). Pyridine-2,6-dicarboxylic acid (2.0 g, 12 mmol) was suspended in dichloromethane (25 mL).…”