Process for the preparation of α-chloromethylene-triorganylphosphorane derivatives
AssigneeBASF SE
InventorsBernd Schaefer, Ernst Buschmann, Gernot Reissenweber
Life of this patent
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Abstract
A process for the preparation of α-chloromethylene-triorganylphosphorane derivatives I (radicals R are C-organic substituents and A stands for CN or CO-B where B is a C-organic or O-organic radical which is inert under chlorination conditions) by chlorination of phosphoranes II with chlorine, wherein the chlorination is carried out in the presence of a mineral base as hydrogen chloride acceptor and the chlorine and base are fed to the reaction mixture concurrently but separately at the rates at which they are consumed. The reaction products I are important intermediates for plant protectants.
Claims7
A process for the preparation of α-chloromethylene-triorganylphosphorane derivatives of the formula I
- in which the radicals R can be the same or different and denote C-organic substituents and A stands for cyano or a group CO-B where B is a C-organic or O-organic radical which has from 1 to 12 carbon atoms and is inert under chlorination conditions, by chlorination of phosphoranes of formula II
- with chlorine, wherein the chlorination is carried out in the presence of an alkali metal hydroxide as hydrogen chloride acceptor and the chlorine and said base are fed to the reaction mixture concurrently but separately at the rates at which they are consumed, such that the pH does not rise above 9 throughout the reaction.
Dependencies are inferred from the claim text.