4-benzyl-1-oxidopyridin-1-ium

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 4-benzylpyridine-N-oxide (8.8 g, 48 mmol) in acetonitrile (50 mL) was added Et3N (9.9 mL, 71.2 mmol). Neat trimethylsilyl cyanide (15.8 mL, 118 mmol) was added dropwise. The resulting solution was heated at reflux for 10 h under nitrogen then after cooling, diluted with CH2Cl2 (150 mL). The resulting solution was washed with NaHCO3 (2×150 mL), dried over Na2SO4 and concentrated in vacuo. The crude compound was purified by filtration on silica gel using EtOAc/n-hexane as eluant to afford the title compound as a pale yellow oil (7.2 g, 78%): 1H NMR (CDCl3) δ4.03 (s, 2H), 7.16 (d, J=7.2 Hz, 2H), 7.20-7.40 (m, 4H), 7.49 (s, 1H), 8.59 (d, J=5.1 Hz, 1H); IR (film) 2240, 1600, 1500 cm−1. The resulting solution was heated at reflux for 10 h under nitrogen after cooling The resulting solution was washed with NaHCO3 (2×150 mL) dried over Na2SO4 concentrated in vacuo The crude compound was purified by filtration on silica gel

Conditions: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 4-benzylpyridine (5 mL, 30 mmol), acetic acid (30 mL) and 30% hydrogen peroxide (10 mL) was heated at 80-90° C. for 5 h. Concentration under reduced pressure gave an oil that was diluted with NaHCO3 (100 mL) and extracted with CH2Cl2 (2×100 mL). The collected organic phase was washed with brine (100 mL) and evaporated in vacuo to give the title compound as a colorless oil (5.68 g, 98%): 1H NMR (DMSO-d6) δ3.90 (s, 2H), 7.15-7.35 (m, 7H), 8.08 (d, J=6.3 Hz, 2H). Concentration under reduced pressure gave an oil that extracted with CH2Cl2 (2×100 mL) The collected organic phase was washed with brine (100 mL) evaporated in vacuo