A new expanded porphyrin, hexadecaphyrin-(18.104.22.168.22.214.171.124.126.96.36.199.188.8.131.52), is reported. It was obtained via the condensation of a hexapyrrolic derivative prepared in turn from a bipyrrole dialdehyde and a stable quaterpyrrole precursor. This hexadecaphyrin contains eight direct α-pyrrole-to-α-pyrrole linkages in its structure. It supports the formation of bimetallic complexes of both zinc and cobalt that are characterized by different conformational structures. Furthermore, a mixed zinc/cobalt macrocycle has been prepared. The cobalt bimetallic complex shows two stable conformations with the same oxidation state that are in equilibrium. All compounds have been characterized by common spectroscopic means, and single crystal X-ray diffraction structures were obtained for all macrocyclic compounds. DFT calculations and transient absorption spectra were used to study the electronic features of the complexes and the effect of conformational changes. This system shows promise as an accumulated heat sensor.
Bibliographical noteFunding Information:
This work was supported by the National Science Foundation (grant CHE-1402004 to J.L.S.) and the Robert A. Welch Foundation (F-0018 to J.L.S.). The work at Yonsei University was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (2016R1E1A1A01943379).
© 2018 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Colloid and Surface Chemistry