CS241191B1 - Method of substituted 2-aminotriazines production - Google Patents

Abstract

The solution lies in the hydrochloride quanyl-O-alkylurea of formula II, wherein R * is alkyl to C6, acts amidoacetal carboxylic acids of formula III wherein R 2 is alkyl C 1 to C 8 or hydrogen and R is C 1 -C 6 alkyl, molar ratios of 1: 0.5 to 1: 10, preferably 1: 1, in polar solvents at -10 degrees Celsius to the boiling point of the solvent, at a maximum pressure of 500 kPa. The above substances have sedative effects in veterinary use and are raw materials in the production of herbicides.

Description

(54) A method for producing substituted 2-aminothiazines

The solution lies in the fact that the hydrochloride quanyl O alkylisomočoviny formula II where R * is alkyl, Ci _{to C6,} acts amidoacetalem carboxylic acids of formula III where R ² is alkyl Ci _to Cg or hydrogen and R is alkyl C1 to _C6 , in molar ratios of 1: 0.5 to 1: 10, preferably 1: 1, in polar solvents at a temperature of -10 ° C to the boiling point of the solvent at a maximum pressure of 500 kPa.

The above-mentioned substances have sedative effects in veterinary use and are raw materials in the production of herbicides.

Fig. 1

Giant. 3 .0R ^X 0R

Ofer.g

H ₁ K-CsNH'HCl

ΉΗ-ΟΝΗ

0R ¹

The invention relates to a new process for producing '2-amino-4-alkoxy-6-alkyl-l, 3,5-triazines of formula I wherein R ¹ is alkyl C · to · Cg and R ^{2 is?} alkyl C 1 to C ₆ or hydrogen.

On the one hand, compounds of this type have sedative effects [Franc. U.S. Pat. 1,380,818 (1964J), for veterinary use, and are raw materials in the production of important herbicides [Palm H. L., Proc. Crop. Prot. Conf. Weeds, 1980; 15 (1), 1-6. Chem. Abstr. 95, 56104 rj.

Aminoalkylalkoxytriazines can be prepared as follows: Six-step synthesis starting from carboxylic nitriles, which react with alcohol to give imidoesters. These are then converted into dicyanamidines which cyclize to substituted chlorotriazine by a two-step reaction with cyanamide. The reactive chlorine is then easily replaced by an alkoxy group [Huffman R. K., Schaefer F. C., J. Org. Chem. 28, 1816 (1963)].

Nucleophilic substitution of 2-alkyl-4,6-dialkoxy-1,3,5-triazines with ammonia [Franc. U.S. Pat. 1,380,818 (1964)] or by reaction of a guanyl-O-methylisourea base with carboxylic acid esters, chlorides, or anhydrides [Franc, pat. 1,380,818 (1964); Kawano K., Odo K .: Nippon Kagaku Zasshi 82, 1672 (1961); Chem. 58, 11, 212 (1963)].

The disadvantages of the above preparations are either multistage synthetic procedures or low yield.

The present invention provides a two-step process for the preparation of 2-amino-4-alkoxy-6-alkyl-1,3,5-triazine of formula I wherein R ¹ is C ₁ -C ₆ alkyl, R ² is C 1 -C ₆ alkyl, or hydrogen, characterized in that quanyl-O-methylisourea hydrochloride of formula II, wherein R ¹ is C 1 -C 6 alkyl, is reacted with an amidacetal of formula III, wherein R ² is C ₍ C ₆ -C ₆₎ or hydrogen and R is alkyl C 1 to C ₆ , in molar ratios of 1: 0.5 to 1: 10, preferably 1: 1 in polar solvents such as alcohols, esters, amides, ketones at a temperature of -10 ° C to the boiling point of the solvent under pressure The product is isolated by filtration and no base is added to the reaction mixture, as has been the case in the previous procedures [Franc. Pat. 1,380,818 (1964); Pískala A .: Coll. Czech. Chem. Commun. 3966 (1967)], on the contrary, the acidic catalytic effect of hydrogen chloride present in the of formula II.

The present invention is illustrated by the following non-limiting example.

Example of reaction of a compound of formula II (wherein R ¹ -C ¹ ) with an amidacetal of formula III (where R ² = H).

Preparation of 2-amino-4-methoxy-1,3,5-triazine.

To a solution of 15.3 g (0.1 mol) of the compound of formula II wherein R ¹ -C ¹ in 100 ml of methanol was added 13.1 g (0.11 mol) of dimethylacetaludimethylformamide and the reaction mixture was left for 0.5 to 3 h at room temperature. 7 g of the desired product melting at 184-188 ° C were formed.

Claims (2)

Subject 1. A process for preparing substituted 2-amino-triazines of formula I where R is alkyl C ^l to C 6 and R ² is a C | C6 or hydrogen hydrochloride quanyl O alkylisomočoviny formula II wherein R ^l is as defined above, characterized in that the hydrochloride quanyl O alkylisomočoviny formula II wherein R ^l is alkyl, Ci _{to C6} , acts by carboxylic amidoacetal Invention, the acid of formula III wherein R is alkyl Cl to C, _O and R ² is alkyl Cl to _C6, or hydrogen in the molar proportions 1: 0.5 to 1: 10, preferably 1: 1, in polar solvents at a temperature of - 10 ° C to the boiling point of the solvent, at a maximum pressure of 500 kPa. 2. Process according to claim 1, characterized in that alcohols, ketones, esters and amides are used as polar solvents.