Method for chlorinating benzaldehyde oximes

A process for preparing chlorobenzaldehyde oximes of general formula (I)

• in which
• X2 is H, C1-C4 alkyl, C1-C4 fluoroalkyl, C1-C4 fluoroalkoxy, C1-C4 alkoxy, fluorine, or CN,
• X3 is H, C1-C4 alkyl, C1-C4 fluoroalkyl, C1-C4 fluoroalkoxy, C1-C4 alkoxy, fluorine, chlorine, or CN,
• X4 is H, C1-C4 alkyl, C1-C4 fluoroalkyl, C1-C4 fluoroalkoxy, C1-C4 alkoxy, fluorine, or CN,
• X5 is H, C1-C4 alkyl, C1-C4 fluoroalkyl, C1-C4 fluoroalkoxy, C1-C4 alkoxy, fluorine, chlorine, or CN,
• X6 is H, C1-C4 alkyl, C1-C4 fluoroalkyl, C1-C4 fluoroalkoxy, C1-C4 alkoxy, fluorine, or CN,
• characterized in that benzaldehyde oxime compounds of general formula (II)
• in which
• X2 to X6 have the meanings stated above,
• are converted in a reaction into compounds of the general formula (I) in the presence of trichloroisocyanuric acid (TCCA) and an amide base.