The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 02, 2020
Filed:
Jul. 19, 2018
Arysta Lifescience Inc., Cary, NC (US);
Vic Prasad, Leawood, KS (US);
David Huang, Kunshan, CN;
Kamal Kataria, Maharashtra, IN;
Christopher Lynn Larson, Cary, NC (US);
Cameron Seath Gibb, Apex, NC (US);
Stephen Cornes, American Canyon, CA (US);
ARYSTA LIFESCIENCE INC., Cary, NC (US);
Abstract
Preparation of O,O-dimethyl phosphoramidothioate and O,O-dimethyl phosphoroamidothioate. A process of making O,O-dimethyl phosphoroamidothioate is described including reacting sulfur with PClto form PSCl, reacting the PSClformed with methanol to form O-methyl phosphorodichloridothioate, and reacting the O-methyl phosphorodichloridothioate formed with methyl lye to form O,O-dimethyl phosphorochloridothioate in solution in CHCl, and reacting the O,O-dimethyl phosphorochloridothioate formed with sodium hydroxide and ammonium hydroxide to form O,O-dimethyl phosphoroamidothioate in solution in CHCl. Reacting the O,O-dimethyl phosphoroamidothioate formed with catalytic dimethyl sulfate to form methamidophos, and reacting the methamidophos formed with acetic anhydride to form N-(methoxy-methylsulfanylphosphoryl) acetamide is also described. Throughout the process, the O,O-dimethyl phosphorochloridothioate and the O,O-dimethyl phosphoroamidothioate formed are maintained in solution in CHClat all times.