US 4,232,153 A · Process for the production of chloro-di (alkylamino)-s-triazines

Abstract

Chloro-bis(alkylamino)-s-triazines are prepared by step-wise replacement of two chlorine atoms of cyanuric chloride with alkylamino groups. Cyanuric chloride, an inorganic base and an alkylamine are continuously fed to a first tubular zone in stoichiometric proportions and reacted therein under turbulent conditions, at an elevated temperature not exceeding 90.degree. C., and for a short reaction time, and the reaction product is continuously fed to a second tubular reaction zone together with stoichiometric quantities of inorganic base and of a second alkylamine, and reacted therein with the latter at an elevated temperature not exceeding 100.degree. C., under turbulent conditions and for a short reaction time.

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Claims22

Dependent claims

In a process for the preparation of chloro-bis(alkylamino)-s-triazine by means of stepwise replacement of two chlorine atoms of cyanuric chloride with alkylamino groups at a temperature not exceeding 90.degree. C. during the first replacement of a chlorine atom and at a temperature not exceeding 100.degree. C. during the second replacement of a chlorine atom, the improvement which comprises;

(a) continuously feeding cyanuric chloride in the form of a solution in an inorganic solvent to the inlet end of a first tubular reaction zone, continuously feeding an inorganic base, a first alkylamine and water to said first tubular reaction zone, said inorganic base and said first alkylamine being fed in at least in part at the inlet end of said first reaction zone, said cyanuric chloride, inorganic base and first alkylamine being fed in in substantially stoichiometric proportions and reacted in said first reaction zone under turbulent conditions to convert substantially completely said cyanuric chloride to 2,4-di-chloro-6-alkylamino-s-triazine, and continuously discharging the reaction product of (a) from the outlet end of said first tubular reaction zone;
(b) continuously feeding said reaction product of (a), upon possible cooling and possible removal of aqueous phase from said reaction product of (a), to the inlet end of a second tubular reaction zone, continuously feeding to said second reaction zone an inorganic base, a second alkylamine and water, said inorganic base of (b) and said second alkylamine being fed in at least in part at the inlet end of said second tubular reaction zone, said 2,4-di-chloro-6-alkylamino-s-triazine, inorganic base of (b) and second alkylamine being fed in in substantially stoichiometric proportions and reacted in said second reaction zone under turbulent conditions to convert substantially completely said 2,4-di-chloro-6-alkylamino-s-triazine into chloro-bis(alkylamino)-s-triazine;
and wherein the reaction times in said first and second reaction zones are less than 10 minutes;
and
(c) continuously discharging the reaction product of (b) from the second reaction zone and recovering the chloro-bis(alkylamino)-s-triazine from said reaction product of (b).

2 more elements

Dependencies are inferred from the claim text.

Description4,133 words

Summary3,206 words

#The present invention relates to the preparation of chloro-di(alkylamino)-s-triazines by means of a continuous process. The chloro-di(alkylamino)-s-triazines are compounds given by the general formula: ##STR1## where R.sub.1, R.sub.2, R.sub.3 and R.sub.4 independently are an atom of hydrogen or an alkyl radical containing from 1 to 5 carbon atoms and possibly also certain other functional groups.

#The chloro-di(alkylamino)-s-triazines are valued herbicides and the most noted compounds belonging to this group are: 2-chloro-4-ethylamino-6-isopropylamino-s-triazine(atrazine), 2-chloro-4,6-di(ethylamino)-s-triazine (simazine) and 2-chloro-4,6-di(isopropylamino)-s-triazine (propazine).

#The herbicidal characteristics of these compounds are described in U.S. Pat. No. 2,891,855 here cited as a reference.

Detailed description927 words

#A reactor consisting of a stainless-steel tube having a length of 10 meters, an internal diameter of 4 mm and an external diameter of 6 mm, is used. The tube is filled with sand grains, 1.2-1.8 mm in size, having a bulk density of 1.48 g/cm.sup.3 and a relative density of 2.6 g/cm.sup.3. The first 2.5 meters of the reactor are intended for the formation of the 2,4-dichloro-6-alkylamino-s-triazine (first reaction zone; stage (a)) and the remaining part is intended for the formation of the chloro-di(alkylamino)-s-triazine (second reaction zone; stage (b)). More particularly, to the inlet end of the first reaction zone there are fed 43 ml/min of a toluene solution containing 15% by weight of cyanuric chloride and, separately, 13.8 ml/min of an aqueous solution containing 12.77% by weight of isopropylamine and 8.85% by weight of sodium hydroxide. In this way the molar ratio between cyanuric chloride, isopropylamine and sodium hydroxide at the input to stage (a) is equal to 1:1:1. Moreover, the reaction of stage (a) is carried out adiabatically with an inlet temperature of the reaction mixture of 18.degree. C. and with an outlet temperature of the said mixture of 55.degree. C. No heat exchange is carried out between the two reaction stages and at the inlet to stage (b) there is fed 11.1 ml/min of an aqueous solution containing 12.15% by weight of monoethylamine and 11.25% by weight of sodium hydroxide. This solution is fed in at a temperature of 18.degree. C. Stage (b) is also carried adiabatically and the temperature of the mass discharged from the reactor is 70.degree. C. 2-chloro-4-ethylamino-6-isopropylamino-s-triazine is separated from the reaction product with a purity of 99%. The reaction yield evaluated with respect to the cyanuric chloride is equal to 98%.

#This test is carried out as in Example 1, delivering to the inlet end of the first reaction zone 37 ml/min of a solution containing 16% by weight of cyanuric chloride in methyl ethyl ketone and, independently, 13.8 ml/min of an aqueous solution containing 12.77% by weight of isopropylamine and 8.85% by weight of sodium hydroxide. The molar ratio in the feed between cyanuric chloride, isopropylamine and sodium hydroxide is thus equal to 1:1:1.

#The inlet temperature of stage (a) is equal to 18.degree. C. and the outlet temperature is 58.degree. C.

Facts

Application

05/922,698Filed 7 Jul 1978

Priority

IT 25474 A/777 Jul 1977

Granted

4 Nov 1980

Term ended

7 Jul 1998

Estimated · how

Pre-1995 term; greater of 17 years from grant or 20 years from filing when eligible. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification3 codes

C07D 251/50
Two nitrogen atoms: with a halogen atom attached to the third ring carbon atom
C07D 251/44
One nitrogen atom: with halogen atoms attached to the two other ring carbon atoms
C07D
Heterocyclic compounds

Process for the production of chloro-di (alkylamino)-s-triazines

Life of this patent

Process for the production of chloro-di (alkylamino)-s-triazines

Life of this patent

Life of this patent

Abstract

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Claims22

Description4,133 words

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Classification3 codes

Life of this patent

Description4,133 words