78168-93-1Relevant academic research and scientific papers
Production of S-substituted isothioureas
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, (2008/06/13)
A process for the production of an S-substituted isothiourea including the functional group STR1 in which R1 is an alkyl, alkenyl, aryl or aralkyl radical, comprising reacting a thiourea including the functional group STR2 with an alpha-activated etherifying agent of the formula in which X is a halogen atom, A is a direct bond or CH2, and Y is an electron withdrawing group, thereby to produce the ether STR3 and in a second step reacting the ether with a compound of the formula R1 SH. The process is particularly applicable to the production of the known herbicide STR4 from the corresponding thiourea where in the first step chloroacetic acid is used to form the S- carboxymethyl isothiourea which is then interchanged with ethyl mercaptan. Higher overall yields and/or economies are thereby achieved.
Process for the preparation of 1-amino-1,3,5-triazine-2,4(1H,3H)-diones
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, (2008/06/13)
A process for the preparation of a herbicidally active 1-amino-1,3,5-triazone-2,4 (1H,3H)-dione of the formula STR1 comprising in a first stage at a temperature from about 0° to 100° C. reacting an isocyanate of the formula with an isothio semicarbazone of the tautomeric formulas STR2 in which R3 and R4 each independently is hydrogen, alkyl, cycloalkyl, aralkyl o alkyl, cycloalkyl, aralkyl or aryl, thereby to form a urea derivative of the tautomeric formulas STR3 in a second stage at a temperature between about -50° and 0° C. reacting the urea derivative with phosgene (COCl2) in the presence of an auxiliary organic base and in the presence of a diluent, at least about 2 mols of phosgene and at least about 2 mols of the auxiliary base being used per mol of urea derivative, thereby to form a 1-alkylideneamino-1,3,5-triazine-2,4(1H,3H)-dione of the formula V STR4 and in a third stage converting the 1-alkylideneamino group to a 1-amino group.
Preparation of 1-amino-1,3,5-triazine-2,4(1H, 3H)-diones
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, (2008/06/13)
Herbicidal 1-amino-1,3,5-triazine-2,4(1H, 3H)-diones of the general formula STR1 are obtained in good yields if an N-substituted O-aryl N-chlorocarbonyl carbamate of the general formula STR2 is reacted with an isothiosemicarbazone of the general formula STR3 or hydrohalide thereof, (R1 to R4 in formulae (I) to (III) having the meanings given in the description), at a temperature between 0° and 50° C., in the presence of an acid-binding agent, the open-chain intermediate products formed thereby are then heated (if appropriate without intermediate isolation), in a second stage, to a temperature between 50° and 150° C. and, finally, in a third stage, the 1-alkylideneamino-1,3,5-triazine-2,4(1H, 3H)-dione formed thereby is hydrolyzed (if appropriate again without intermediate isolation) in an acid medium.
Process for the preparation of 1-amino-1,3,5-triazine-2,4(1H, 3H)-dione compounds
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, (2008/06/13)
A process for the preparation of a 1-amino-1,3,5-triazine-2,4(1H, 3H)-dione compounds comprising the steps of reacting an N-substituted imido-dicarboxylic acid diaryl ester with an isothiosemicarbazone at a temperature of between 50° and 150° C. to form a 1-alkylidene-amino-1,3,5-triazine-2,4(1H, 3H)-dione reaction product; and thereafter, hydrolyzing the reaction product in an acid medium. The reaction product need not be separated from the reaction mixture before the hydrolysis step. Certain novel 1-amino-1,3,5-triazine-2,4(1H, 3H)-dione compounds are provided. The compounds are useful as herbicides.
