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Machine translation
1. (WO1980000341) PROCESS FOR PRODUCING TRICHLORO-2,4,5-PHENOXYACETIC ACID
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1980/000341    International Application No.:    PCT/FR1979/000071
Publication Date: 06.03.1980 International Filing Date: 30.07.1979
IPC:
C07C 51/363 (2006.01), C07C 59/70 (2006.01)
Applicants:
Inventors:
Priority Data:
7823658 07.08.1978 FR
Title (EN) PROCESS FOR PRODUCING TRICHLORO-2,4,5-PHENOXYACETIC ACID
(FR) PROCEDE DE FABRICATION DE L"ACIDE TRICHLORO-2,4,5 PHENOXYACETIQUE
Abstract: front page image
(EN)A method for producing trichloro-2, 4, 5 phenoxyacetic acid appropriate for use as active material in herbicide compositions. The method comprises a first step of changing trichloro-2, 4, 5 phenoxyacetic acid into diazonium chloride, by action of an alkali metal nitrite and hydrochloric acid at a temperature ranging from 0 to 10 C, according to the reaction formula: (FORMULA) wherein Me represents an alkali metal atom, then a second step of heating the diazonium chloride at a temperature ranging from 40 to 70 C, in presence of hydrochloric acid and cuprous chloride. Such method avoids the use, as initial material, of trichloro-2, 4, 5 phenol, compound which is susceptible of containing tetrachloro- 2, 3, 7, 8 dibenzoparadioxine as impurity, the toxicity of which is very high.
(FR)Procede de fabrication de l"acide trichloro-2,4,5 phenoxyacetique utilisable comme matiere active dans les compositions herbicides. Le procede consiste en une premiere etape a transformer l"acide trichloro-2,4,5 phenoxyacetique en son chlorure de diazonium, par action d"un nitrite de metal alcalin et de l"acide chlorhydrique a une temperature comprise entre 0 et 10 C, selon le schema reactionnel: (FORMULE) dans lequel Me represente un atome de metal alcalin, puis en une deuxieme etape a chauffer le chlorure de diazonium, a une temperature comprise entre 40 et 70 C, en presence d"acide chlorhydrique et de chlorure cuivreux. Le procede selon l"invention evite l"utilisation, comme matiere de depart, du trichloro-2,4,5 phenol, compose susceptible de contenir comme impurete du tetrachloro-2,3,7,8 dibenzoparadioxine dont la toxicite est tres elevee.
Designated States:
Publication Language: French (FR)
Filing Language: French (FR)