pyrethrin

Place syntheses below =**RETROSYNTHESIS OF PYRETHRIN:**= =

= =**SYNTHESIS OF PYRETHRIN:**=



=HOW IT IS SYNTHESIZED:= Jessica: This synthesis looks workable. The reterosynghesis will start at the product and break it down until you reach the starting material. You don't need to put in reagents for that (see Tim Maynard's post on the diynediol, and Ana Baird's post on the alkene for an example).If you include the reterosynthesis and a brief paragraph, this post will be complete Bruce Bondurant

From Sean Pitcher:

I have come up with the same synthesis as Jessica, albeit from a slightly different starting point. The most effective synthesis seems pretty much comes down to the path Jessica outlined regardless of starting point.

Natural Pyrethrin decays rapidly in sunlight, making it a true "green" pesticide in that it disappears leaving no harmful effects. In that fact lies its problem, as it is expensive to produce from natural sources(due to the above mentioned shortages) and its killing time short. Artificially synthesized pyrethrins(the family of which is called pyrethroids) persist in the environment and improve killing time therefore economic value. Two examples of pyrethroids are: Permethrin Allerthin

While these chemicals last longer in the environment, care must be taken with their use, as bees and dragonflies are ffected by pyrethroids. Bees and dragonflies are pollinating insects,and losses in their species must be carefully monitored. In the last few years, the sudden occuring and ongoing death of millions of bees in California is of current concern to environmental scientists. Interestingly, 10 times the lethal dose of pyrethroids for aquatic invertebrates have been found in California waterways, with residential runoff accounting for higher levels than agricultural runoff. After testing the final effluent from various water treatment plants in California, pyrethroids were still found to be present(1). Also interesting, according to Wikipedia, " An unpublished study, currently only available in abstract form,[|[][|8][|]][|[][|9][|]] led by lead author Irva Hertz-Picciotto, professor in the Department of Public Health Sciences at University of California, Davis, suggested a correlation between pyrethrins and [|autism]. In the study of 500 children (with or without autism), the 138 children with autism and their mothers were twice as likely to "report using pet shampoos and other household products containing pyrenthrins than other mothers". However, no causal link was established and further studies were called for."

A good suggestion may be that we synthesize the molecule a little closer to natures design.



(1) Author unlisted, Date unlisted, Pyrethroid, From Wikipedia the free enclylopedia, retrieved from http://en.wikipedia.org/wiki/Pyrethroid