A sulfone mediated approach presumably did produce Me a-fluorochrysanthemate I but, if formed, the latter immediately underwent dehydrofluorination under the strongly basic reaction conditions. The cis- and trans-isomers of Me b- and g-fluorochysanthemates II and III were concomitantly obtained by treating 3-fluoro-2,5-dimethyl-2,4-hexadiene with N2CH2CO2Me in the presence of catalytic amts. of Rh(OAc)2. After enzymic and chromatog. sepn. the four individual components were converted to the m-phenoxybenzyl esters. [on SciFinder (R)]