Chloroalkyl pyridinium hydrochloride compounds and processes for their preparation

A process for the preparation of 3-chloromethyl pyridinium hydrochloride which comprises the steps of:

• a) generating a solution or a dispersion comprising 3-hydroxymethyl pyridinium hydrochloride in a medium comprising at least one non-solvent for 3-chloromethyl pyridinium hydrochloride;
• b) admixing thionyl chloride with said solution or dispersion generated in step (a) to generate a reaction mixture;
• and
• c) reacting thionyl chloride with 3-hydroxymethyl pyridinium hydrochloride to form 3-chloromethyl pyridinium hydrochloride, at least a portion of which forms as a solid in the reaction mixture.

A process for the preparation of substantially pure, substantially non-dusting 3-chloromethyl pyridinium hydrochloride comprising the steps of:

• a) generating a solution or dispersion comprising 3-hydroxymethyl pyridinium hydrochloride in a medium comprising toluene, by reacting in said medium, 3-hydroxymethyl pyridine with at least about 1 equivalent of hydrogen chloride, based on the number of pyridine nitrogen equivalents;
• b) admixing thionyl chloride with said solution or dispersion generated in step (a) to form a reaction mixture;
• c) heating the reaction mixture to a temperature ranging from about 75.degree. C. to about 90.degree. C. for a period of time ranging from about 0.5 to about 10 hours;
• d) heating the reaction mixture to a second temperature ranging from about 90.degree. C. to about 100.degree. C. Ad maintaining said second temperature within said range for a period of time of from about 3 minutes to about 6 hours;
• and
• e) recovering 3-chloromethyl pyridinium hydrochloride from the reaction mixture in a substantially high yield.