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The reaction of alcohols with (pentafluorophenyl)dipyrromethane (PFP-DPM) under basic conditions has been studied, giving access to the corresponding alkoxy-substituted DPMs. This method represents the first high-yielding substitution of PFP-DPM carried out with oxygen nucleophiles. Condensation of these prefunctionalized DPMs with aldehydes led to the respective trans-A2B2 porphyrins. This pathway allows a simple synthesis of multifunctionalized tetrapyrroles. Oxidation and boron complexation of these DPMs, on the other hand, led to meso-functionalized difluoroboraindacenes (BODIPYs). In addition, nucleophilic substitution of PFP-BODIPY with sodium azide led to a 4-azidophenyl derivative, thus further enhancing the scope of reactive sites suitable for subsequent transformations.

meso-Substituted trans-A2B2-porphyrins bearing specific patterns of substituents are crucial building blocks in porphyrin-based biomimetic systems and molecular materials and can be used for the construction of well-defined porphyrin-based architectures. A new stepwise and rational synthesis of functionalized trans-A2B2-porphyrins is reported in which for the first time donor–acceptor-substituted cyclopropane precursors (d–a cyclopropanes) are exploited. The three presented d–a cyclopropanes are readily accessible in a multi-gram scale and serve as aldehyde equivalents in the reaction with an excess of pyrrole to afford the corresponding dipyrromethanes (DPMs). The three DPMs were synthesized in yields of 60–74%. They are stable in purified form in the absence of light and air and were subsequently condensed with a wide range of aliphatic and aromatic aldehydes bearing electron-donating or electron-withdrawing substituents followed by oxidation to form the corresponding trans-A2B2-porphyrins. Fourteen functionalized porphyrins were synthesized in yields of 14–31%, indicating the broad scope of the synthetic procedure. The possibility to introduce key functional groups is emphasized, which enables subsequent modification of these porphyrins with moieties inducing biological activity. Modification of the tetrapyrroles may occur by addition to one of the porphyrin peripheral double bonds, the use of substituents of the aryl groups or via the methoxycarbonyl group at two of the meso-substituents. Three examples of porphyrins were converted into the corresponding 7,8-dihydroxychlorins by osmium-mediated dihydroxylation and one of the resulting chlorins was subjected to saponification to give a highly polar chlorin dicarboxylic acid. A 4-bromophenyl-substituted d–a cyclopropane was prepared by rhodium-catalyzed cyclopropanation and then transformed into a DPM which was subsequently condensed to a porphyrin. Its Zn complex allowed a Heck reaction to afford the functionalized bis(alkenyl)-substituted trans-A2B2-Zn-porphyrin.