| 摘要 |
Herbicidally active substituted phenyl carbamates I <IMAGE> I in which R1 represents a C1-C6 alkyl group, a C3-C6 cycloalkyl group or an aryl group, which aryl group may be substituted by a halogen atom and/or a C1-C6 alkyl group and/or a trifluoromethyl group, and R2 represents a C1-C6 alkyl, C2-C6 alkenyl or C2-C6 alkynyl group that may be substituted by a terminal halogen atom, are prepared by reacting N-hydroxyphenyl carbamates II <IMAGE> II with either isocyanates R1-N=C=O or amino chlorides R1-NH-COCl in an aqueous medium thus avoiding the use of organic solvents. The end product I may be extracted from the aqueous slurry into a water-immiscible solvent. The N-hydroxyphenyl carbamates II can be prepared by reacting 3-aminophenol with chloroformates in an aqueous medium, and the resulting product may be reacted in situ, without isolation, with isocyanates, in the same reaction vessel. Stabilized herbicidal compositions containing compounds I may be prepared by suspending the compounds I in a liquid phase comprising one or more oily components and one or more surfactants.
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