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Regioselective phenylene-fusion reactions of Ni(ii)-porphyrins controlled by an electron-withdrawing meso-substituent.

ABSTRACT: Oxidation of 10,15,20-triaryl Ni(ii)-porphyrins bearing an electron-withdrawing substituent at the 5-position with DDQ and FeCl₃ gave 10,12- and 18,20-doubly phenylene-fused Ni(ii)-porphyrins regioselectively. A doubly phenylene-fused meso-chloro porphyrin thus prepared was reductively coupled to give a meso-meso linked dimer, which was further converted to a quadruply phenylene-fused meso-meso, β-β, β-β triply linked Zn(ii)-diporphyrin via inner-metal exchange followed by oxidation with DDQ and Sc(OTf)₃. As compared to the usual meso-meso, β-β, β-β triply linked Zn(ii)-diporphyrin, this π-extended porphyrin dyad exhibits a smaller HOMO-LUMO gap and a larger two-photon absorption cross-section.

SUBMITTER: Fukui N

PROVIDER: S-EPMC6013929 | biostudies-literature |

REPOSITORIES: biostudies-literature

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