Method for preparing 2,5-dihalo- and 2,5,6-trihalopyridines
AssigneeThe Dow Chemical Company
InventorsStanley D. McGregor, Herman O. Senkbeil
Life of this patent
Estimating the term…
Abstract
A method for preparing 2,5-dihalo- and 2,5,6-trihalopyridines corresponding to the formula ##SPC1## Wherein each X independently represents chloro, fluoro or bromo and R represents hydrogen, chloro, fluoro or bromo which comprises reacting a halohydrazinopyridine of one of the formulas ##SPC2## With an excess of an aqueous alkali metal hydroxide in the presence of a reaction medium from the group consisting of loweralkanols of 1 to 4 carbon atoms and loweralkylglycols of 2 to 4 carbon atoms.
Claims11
A method for preparing 2,5-dihalopyridine corresponding to the formula:
- ##SPC7##
- wherein each X independently represents chloro, fluoro or bromo which comprises reacting at a temperature of from about 50.degree.C to the reflux temperature a halohydrazinopyridine of one of the formulas ##SPC8##
- with an aqueous alkali metal hydroxide in the presence of a reaction medium selected from the group consisting of lower-alkanols of 1 to 4 carbon atoms and loweralkylglycols of 1 to 4 carbon atoms.
A method for preparing 2,5,6-trihalopyridine corresponding to the formula:
- ##SPC9##
- wherein each X independently represents chloro, fluoro or bromo which comprises reacting at a temperature of from about 50.degree.C to the reflux temperature a halohydrazinopyridine of the formula ##SPC10##
- with an aqueous alkali metal hydroxide in the presence of a reaction medium selected from the group consisting of loweralkanols of 1 to 4 carbon atoms and loweralkylglycols of 1 to 4 carbon atoms.
Dependencies are inferred from the claim text.