L-Methoxy-2-methylpyridinium methyl

A. l-Methoxy-2-methylpyridinium methyl sulfate. In a 1-1. three-necked flask equipped with a Hirshberg stirrer, a thermometer which extends deep into the flask, and a 250-ml. pressureequalizing, dropping funnel fitted with a calcium chloride diying tube is placed 109 g. (1.0 mole) of diy powdered 2-picoline-l-oxide (Note 1). The stirrer is started at a slow rate, and 126 g. (1.0 mole) of dimethyl sulfate (Note 2) is added dropwise at a... 

It has been suggested that deuteration of N-methyl-2-pyridone occurs at the methyl group.Base-catalyzed hydrogendeuterium exchange, however, takes place at the 2- and 6-positions of 4-pyridones (MI-686, R = H, CH3, Br) and 4-methoxy-l-methylpyridinium tetrafluoroborate (MI-687) and at the 6-posi-tion of Mmethyl-2-pyridone in deuterium oxide via an ylide mechanism. The rates of exchange relative to A-methyl-4-pyridone are ... 

A-methyl-2-pyridone OO2O at 100"), 10"° 4-methoxy-l-methylpyridinium tetrafluoroborate (Xn-687) (CH3OD at 40°), The high rate of... 

Methoxy-l-methylpyridinium iodide (XI-725) and benzylmagnesium iodide in ether give 2-benzyH,2-dihydro-4-methoxy-l-methylpyridine, an air-sensitive red oil, which forms 2-benzyl-2,3-dihydro-l-methyl-4-pyridone when heated with sodium hydroxide in aqueous methanol." ... 

As would be expected, quaternary derivatives of 2- or -4-alkoxy- or -aryloxy-pyridine can easily be converted into 1-alkyl-2- or -4-pyridones. Several examples are on record392, 942, 949, 962 in all of which reaction was effected by alkali. 4-Methoxy-l-methylpyridinium iodide is also converted into l-methyl-4-pyridone by heat . 

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