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US 4,283,338 AGranted
Process for producing O,O-dialkyl dithiophosphoric acid esters
AssigneeBoots Hercules Agrochemicals Co.
InventorJames Minn
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Abstract
Disclosed is a method for improving the yield of dialkyl dithiophosphoric acid esters produced by the Lewis acid catalyzed reaction of an O,O-dialkyl dithiophosphoric acid and an organic chloride. More specifically, the method concerns the improvement wherein the reaction is conducted under sufficient pressure to maintain the liberated hydrogen chloride in the reaction system during the course of the reaction.
Claims6
In the process defined by the reaction:
- ##STR3## where R is an alkyl group having 1 to 4 carbon atoms and R'Cl is an organic chloride which contains at least one acid-replaceable chlorine atom on a carbon atom attached to oxygen, sulfur or nitrogen by a single bond, which reaction is effected in the presence of a catalytic amount of zinc chloride, ferrous chloride or stannous chloride and in the absence of a sequestering agent for the hydrogen chloride liberated by the reaction, the improvement which comprises conducting said reaction under sufficient pressure to maintain the liberated hydrogen chloride in the system during the course of the reaction.
Dependencies are inferred from the claim text.