Reaction #1256709

Reaction equation

6

4-(3,5-dimethyl-pyridin-4-yl)-3,5-dimethyl-phenol

iodomethane

→

methyl pyridinium iodide salt

4-(4-hydroxy-2,6-dimethyl-phenyl)-1,3,5-trimethyl-pyridinium iodide

Solvents

methanol

Conditions

Workup

1. 1
   TemperatureAfter cooling to room temperature
2. 2
   Concentrationthe mixture was concentrated in vacuo

Procedure

To a stirring solution of 6 (0.113 g, 0.500 mmol) in anhydrous methanol (10 mL) was added dropwise iodomethane (0.5 mL, 0.660 g, 2.75 mmol) at room temperature under N2. The reaction mixture was then stirred at 60° C. under N2 overnight. After cooling to room temperature, the mixture was concentrated in vacuo to give the corresponding methyl pyridinium iodide salt as an analytically pure yellow solid (0.184 g, 99.4%). mp 257-258° C.; 1H NMR (500 MHz, DMSO-d6): δ 9.562 (s, 1H), 8.898 (s, 2H), 6.645 (s, 2H), 4.295(s, 3H), 2.015 (s, 6H), 1.760 (s, 6H); 13C NMR (125 MHz, DMSO-d6): δ 157.588, 157.448, 143.158, 136.942, 134.675, 124.179, 114.988, 47.297, 19.162, 16.527; MS (ESI): m/z 242.4 [(M−I)+, 100]; Anal. Calcd. For C16H20INO·H2O: C, 49.62; H, 5.73; N, 3.62; I, 32.77. Found: C, 50.08; H, 5.52; N, 3.65; I, 33.49.

Source