Nitrokemia Ipartelepek

Nehezvegyipari Kutato Intezet

Mta Mezogazdasagi Kutato Intezet

Laszlo Lendvai

Zoltan Kolonics

Jeno Pelyva

Csaba Soptei

Bela Karacsonyi

Elemer Tomordi

Sandor Balint

Janosne Benczik

Csaba Kayos

Sandor Laszlo

Lajos T Nagy

Miklos Kovacs

Miklos Nadasy

Dezso Sebok

Andras Horvath

Laszlo Legradi

Balint Nagy

Andras Vass

Ervin Vertesi

Kornelia Domjan Nee Pinter

Endre Sumegi

Gyorgy Huszak

Bela Gyorfi

Laszlo J Szabo

Andras Haas

Taszlo Kulcsar

Erzsebet Dioszegi

Ferenc Fodor, Deceased

Sandor Silye

K Istvan Vecsey

The invention relates to an improvement of a process for preparing N-phosphonomethyl-glycine by oxydation of N-phosphonomethyl-imino-diacetic acid in an aqueous sulphuric acidic medium with hydrogen peroxide. A characteristic feature is using a waste acid liquor as reaction medium formed as aqueous sulphuric acid and obtained after the separation of N-phosphonomethyl-glycine when carrying out oxydation. This solution is optionally diluted with water until a concentration of 12-18 weight % of sulphuric acid and 3-5 weight % of N-phosphonomethyl-glycine.

Process for preparing N-phosphonomethyl-glycine

The invention relates to the preparation of N-phosphono-methyl-imino-diacetic acid from the calcium salt of imino-diacetic acid in a simplified synthesis. The process comprises in that the imino-diacetic acid calcium salt is heated with concentrated hydrochloric acid in a molar ratio of 2-3:1 at a temperature between 50.degree.-100.degree. C., the obtained imino-diacetic acid hydrogen-chloride is separated then dissolved in water and is reacted with phosphorous acid in a molar ratio of 1.0-1.2:1 calculated for imino-diacetic acid hydrogen chloride and with the aqueous solution of formaldehyde in a molar ratio of 1.0-1.4:1 under stirring, and the obtained product is isolated.

Process for preparing N-phosphono-methyl-imino-diacetic acid

Process for the preparation of

The invention relates to an improved method for the preparation of a 2',6'-dialkyl-N-alkoxymethyl-2-chloro-acetanilide compound of the general formula (I), ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are identical or different and stand for straight-chained or branched C.sub.1-4 alkyl groups. According to the invention a dialkyl aniline of the general formula (II), ##STR2## wherein R.sub.1 and R.sub.2 are as defined above, is treated with aqueous formaldehyde solution in an apolar solvent at a temperature of 30.degree. to 80.degree. C., the solution of the resulting oxymethyl derivative formed with said apolar solvent is separated from the aqueous formaldehyde solution at an elevated temperature and then dehydrated, the resulting azomethine derivative is reacted with chloroacetyl chloride in the same apolar solvent medium, the resulting chloromethyl compound is reacted with an alcohol of the general formula (V),

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Fuzfogyartelep, Hungary

Laszlo Lendvai