Morand, Peter,Soucy-Breau, Chantal.2009-03-202009-03-2019901990Source: Masters Abstracts International, Volume: 31-01, page: 0316.9780315680098http://hdl.handle.net/10393/5712http://dx.doi.org/10.20381/ruor-14498Analogues and derivatives of naturally occurring $\alpha$-terthienyl 3 have been synthesized by using the nickel-catalyzed Grignard-Wurtz cross-coupling reaction. This method has proven useful for the introduction of non-polar substituents on 2-bromothiophene which upon subsequent cross-coupling with 5-iodo-$\alpha$-dithienyl 185 led to a successful variety of 5-substituted $\alpha$-terthienyls. Derivatives of $\alpha$-terthienyl bearing polar functional groups were synthesized either by: (1) introduction of electron-withdrawing and electron-donating at C-5 and C-5$\sp{\prime\prime}$; or (2) chain extension from an appropriate substituted derivatives. In order to establish structure/activity relationships, various substituent at C-5 on the aromatic ring were made. Among the derivatives of $\alpha$-terthienyl, compound 165 was synthesized by the palladium-catalyzed coupling reaction with CuI. By adapting this methodology on $\alpha$-dithienyls, the reaction was found to be useful for coupling aryl halides such as 5-iodo-$\alpha$-dithienyl 185 with a variety of substituted 1$\sp\prime$-alkynes derivatives. A series of functional $\alpha$-dithienyl acetylene derivatives were made. The biological activity of $\alpha$-terthienyl and $\alpha$-dithienyl derivatives, as determined by feeding trials with the mosquito larvae (Aedes atropalpus) and brine shrimp, is discussed in light of the relative toxicities of these compounds.191 p.Chemistry, Organic.Synthesis of naturally occurring phototoxic thiophenes and their derivatives.Thesis