Iodo-lactones, a process for their preparation and their use in separating cis acids from cis/trans acids.

摘要

Novel iodo-lactones of the following general formula
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wherein each of the groups X<1> and X<2> represents a fluorine, chlorine or bromine atom or a hydrocarbyl group. The iodolactones are useful in separating cis-acids of the following formula
<CHEM>
wherein X<1> and X<2> have the above meaning from mixtures with the corresponding trans-acid: the cis-acid is an important intermediate in the manufacture of pyrethroid insecticides.