| 摘要 |
<p>A process for the preparation of a compound of the general formula <CHEM> in which each of R<1> and R<2> independently represents an alkyl group and each of R<3> and R<4> independently represents a hydrogen atom or an alkyl group, which comprises reacting a compound of the general formula <CHEM> in which R<1>, R<3> and R<4> have the meanings given above, with an alkylating agent selected from an alkene, an alkyl halide, an alkanol, an alkyl ester of a carboxylic acid, or a dialkyl ether, the reaction being conducted in the liquid phase in the presence of hydrogen fluoride. The compound of the general formula I in which R<1> is methyl R<2> is isopropyl and R<3> and R<4> are both hydrogen, can be readily converted by methods analogous to known methods into the compound 3-(3-methyl-4-isopropylphenyl)-1,1-dimethylurea, which is an herbicide.</p> |
