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We present herein a rare and efficient method for the creation of vinylated all carbon quaternary centers via Fe-catalyzed cross-electrophile coupling of vinyl halides with tertiary alkyl methyl oxalates. The reaction displays excellent functional group tolerance and broad substrate scope, which allows cascade radical cyclization and vinylation to afford complex bicyclic and spiral structural motifs. The reaction proceeds via tertiary alkyl radicals, and the putative vinyl–Br/Fe complexation appears to be crucial for activating the alkene and enabling a possibly concerted radical addition/C–Fe forming process.

Fe3O4/CdSe/ZnS magnetic fluorescent bifunctional nanocomposites were obtained by depositing heterogeneous semiconductor on magnetic nanoparticles. The structure and properties of the Fe3O4/CdSe/ZnS nanocomposites were fully characterized by TEM, XPS, XRD, SQUID and PL. The results indicate that the Fe3O4/CdSe/ZnS nanocomposites are superparamagnetic and are about 8 nm in size. The quantum yield of the nanocomposites increases from 2–3% in Fe3O4/CdSe to 10–15% in Fe3O4/CdSe/ZnS, together with a red shift of both the absorption peak and PL band. The increase of quantum yield is due to the passivation of the surface of magnetic-CdSe nanocomposites with a ZnS layer.