The effect of methoxy substituent on the spectral and electrochemical properties of novel manganese (III) phthalocyanines

This study primarily reports how changing the number of distant substituent methoxy groups in manganese(III) phthalocyanines affects their complex formation and physical, chemical, spectral, electrochemical, and spectroelectrochemical properties. In this study, novel two alpha (nonperipheral) and two beta (peripheral) substituted Mn(III)(OAc)Pc complexes involving 4-methoxyphenylthio or 2,4,6-trimethoxyphenylthio groups were synthesized using their metal-free analogs, and purified. Molecular characterization of the complexes was achieved by elemental analyses and spectral methods of FT-IR, UV– Vis, and MALDI-TOF-Mass. The redox behaviors of the Mn(III)(OAc)Pc complexes were explored using electrochemical and in situ spectroelectrochemical analyses. The electrochemical surveys indicated that the complexes had manganese metal-based and phthalocyanine (Pc) ring-based redox processes. This detailed study examined how distant substituents affect the redox behaviors of the novel Mn(III)(X)Pc type complexes, which have rarely been investigated in the literature. Distinct spectral and in situ spectroelectrochemical color changes as well as their rich redox behaviors showed that Mn(III)(OAc)Pc type complexes are suitable for electrochromic devices.