Oligomerization Reactions of Bis(ethynyl)tetraphenylporphyrin Derivatives by Glaser–Hay Coupling Reaction: Isolation and Characterization of Dimer, Trimer, and Tetramer

Abstract

The Glaser–Hay coupling reaction of a tetraphenylporphyrin derivative having two acetylenes in the quasi-trans positions was carried out. Although this oxidative coupling reaction has high reactivity and produces various butadiynylene oligomers, the degree of oligo­merization was low. A large substrate and/or product might decrease the frequency factor of the Arrhenius equation and the resultant rate constant. This finding is in agreement with that of the one-pot synthesis of structurally well-defined porphyrin oligomers, such as trimers and tetramers, which are used frequently in the field of advanced materials.

Key words

nanoscience - porphyrin wires - Glaser–Hay coupling - oligomers

• References

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