| abstract |
A process for the preparation of (Z)-cyanoalkenylcyclopropanecarboxylic acid compounds, including a step of isomerizing an (E)-cyanoalkenylcyclopropanecarboxylic acid compound (1) into a (Z)-cyanoalkenylcyclopropanecarboxylic acid compound (2) in the presence of at least one isomerization catalyst selected from the group consisting of bromine, hydrogen bromide, carboxylic acid bromides, phosphorus bromides, N-bromoimides, N-bromoamides, alkylsilyl bromides, thionyl bromide, boron bromides, aluminum bromides, thiols, disulfides, thiocarboxylic acid compounds, nitric acid, and nitrates (salts). In formulae (1) and (2), R1 is optionally substituted alkyl or a halogen atom; and R2 is a hydrogen atom, optionally substituted alkyl, or optionally substituted benzyl. |