Patent GB-957276-A (GB)
Title: Process for the production of chlorine derivatives of alpha-picoline and novel 2-(trichloromethyl) pyridines
IPC: C05D9/00
Filed: 1962-11-15
Abstract: Compositions comprising 6 - chloro - 2 - (trichloromethyl) pyridine are useful as nitrification inhibitors and may be fertilizer compositions which also contain organic and/or reduced nitrogen, preferably in the form of ammonia or ammonium ions. Incorporation of the fertilizer compositions in a soil growth medium results in an improved growth medium.  An example is given in which 6-chloro-2-(trichloromethyl) pyridine is dissolved in an aqueous ammonium fertilizer composition to produce a soil treating composition.ALSO:A process for the production of 6-chloro-2-(trichloromethyl) pyridines which contain from 0 to 3 chlorine atoms in the 3, 4, and/or 5 nuclear positions comprises chlorinating a -picoline or its chlorination products with chlorine at elevated temperatures and includes the step of substituting chlorine in the 6-position of a 2-(trichloromethyl)-pyridine which is either employed as the direct starting material or is an intermediary component in a chlorination reaction mixture, said 2-(trichloromethyl)-pyridine containing from 0 to 3 chlorine atoms in the 3, 4, and/or 5 positions, by chlorinating with chlorine at elevated temperatures under conditions which permit or favour the removal of HCl from the vicinity of said 2-(trichloromethyl)-pyridine or nuclear 3, 4, and/or 5 substitution products thereof.  The invention also comprises the compounds 6-chloro-2-(trichlomethyl)-pyridine, 3, 6-dichloro-2-(trichlomethyl)-pyridine, 5, 6-dichloro-2-(trichloromethyl)-pyridine and 3, 4, 5, 6-tetrachloro-2-(trichloromethyl)-pyridine. The chlorination is preferably carried out under conditions which do not permit or favour the removal of HCl from the vicinity of the a -picoline or 2-(mono-) or (dichloromethyl)-pyridines present in the reaction mixture.  The reaction is preferably carried out in the liquid phase, the chlorine being employed in the gaseous state.  The removal of HCl from the vicinity of the 2-(trichloromethyl)-pyridine is favoured by passing an excess of gaseous chlorine through the reaction mixture and by conducting the chlorination under anhydrous conditions and at a high temperature. The chlorination may be carried out in an inert solvent and in the presence of actinic or ultraviolet light.  A catalyst such as a Lewis acid may be present.  When a -picoline is employed as starting material it is preferably saturated with HCl prior to carrying out the chlorination to give a liquid picoline hydrochloride composition. In examples numerous chlorinated derivatives of a -picoline are obtained.ALSO:Compositions comprising 6-chloro-2-(trichloromethyl) pyridine (I), 3,6-dichloro-2-(trichloromethyl) pyridine (II), 5,6-dichloro-2-(trichloromethyl) pyridine (III), 3,5,6-trichloro-2-(trichloromethyl) pyridine (IV) or 3,4,5,6-tetrachloro-2-(trichloromethyl) pyridine (V) are useful as pesticides of various types.  Compound (V) which may also contain 3,4,5-trichloro-2-(trichloromethyl) pyridine may be mixed with dispersing agents and dispersed in water to give herbicidal compositions.  Aqueous compositions containing one of compounds (I), (III), (IV) and (V) are used as nematocides.  Compounds (II) or (III) dispersed in a malt yeast agar medium inhibit the growth of microorganisms.  Compositions containing compound (I) are used as insecticides and as nitrification inhibitors, the latter compositions being, for example, fertilizer compositions which may also contain organic and/or reduced nitrogen, preferably in the form of ammonia or ammonium ions.