H2TPP organocatalysis in mild and highly regioselective ring opening of epoxides to halo alcohols by means of halogen elements

Facile synthesis of vicinal halohydrins via organocatalytic halogen nucleophile-induced regioselective opening of epoxides

Background:

The calix[4]pyrrole is reported as a novel organocatalyst for regioselective ring opening of epoxides under mild reaction conditions.

Methods:

The reaction involves elemental halogen as a nucleophile to afford vicinal halohydrins in good to excellent yield (75-95%).

Results :

The reactivity of the halide anion in the reaction is governed by different factors, including solvent polarity, temperature and non-covalent interactions of the functional group present on calix[4]pyrrole moiety with halide ions.

Conclusion:

An efficient methodology has been developed for the regioselective synthesis of halohydrins in good to excellent yields.

A potent larvicidal agent against Aedes aegypti mosquito from cardanol

Cardanol is a constituent of Cashew Nut Shell Liquid that presents larvicidal activity against Aedes aegypti. The isolation of cardanol is somewhat troublesome, however, in this work we describe an efficient and inexpensive method to obtain it as a pure material. The compound was used as starting material to make chemical transformation leading to saturated cardanol, epoxides and, halohydrins. These derivatives were tested for toxicity against Aedes aegypti larvae. The results showed that iodohydrins are very promising compounds for making commercial products to combat the vector mosquito larvae presenting a LC50 of 0.0023 ppm after 72 h of exposure.