Synthesis of 5,10,15,20-meso-unsubstituted and 5,10,15,20-meso-substituted-21,23-ditellura/diselena core-modified porphyrinogens: oxidation and detection of mercury(II)

Tellurium and selenium incorporated 5,10,15,20-meso-unsubstituted-21,23-ditellura/diselena coremodified porphyrinogens (N2Te2 and N2Se2), 5,10,15,20-meso-unsubstituted-21-tellura/selena coremodified porphyrinogens (N3Te and N3Se) and fully substituted meso-carbons porphyrinogens (N2Te2, N2Se2 and higher analogs) are synthesized by 3 + 1 condensation of tellurophene/ selenophene dipyrranes and their corresponding diols in the presence of BF3-etharate or BF3-methanol. The meso-unsubstituted and substituted porphyrinogens were oxidized with chloranil/0.1% aqueous FeCl3 in CHCl3 at room temperature to obtain the corresponding porphines and porphyrins which are further reduced to corresponding chlorin and bacteriochlorin, whereas the fully mesosubstituted porphyrinogens were found to be good ligands for Hg2+. The structures of the products were characterized by IR, H-1, C-13, Te-125, Se-77 NMR, CHN analysis, mass spectrometry and single-crystal XRD.