Processes for preparing pesticidal intermediates

摘要

The invention relates to a process for the preparation of a compound of formula (I): wherein: R<1> represents C1-4 haloalkyl, fluorine, chlorine or bromine; and R<2> represents hydrogen or C1-4 alkoxy; which process comprises the reaction of the corresponding ortho-nitrochlorobenzene of formula (II): wherein R<1> and R<2> are as hereinbefore defined, with: (a) cuprous cyanide and a source of bromide selected from hydrogen bromide, bromine and a tetraalkylammonium bromide; optionally in the presence of an alkali metal bromide or an alkaline earth metal bromide; or (b) an alkali metal cyanide or a tetraalkylammonium cyanide, in the presence of cuprous bromide and a phase transfer catalyst; or (c) cuprous cyanide and lithium iodide.