The Synthesis, Characterization, Electrochemical and Spectroelectrochemical Properties of Novel Unsymmetrical Phthalocyanines Containing Naphthoic Acid and Di-tert-butylphenoxy Groups

• Published in: Synthetic metals Vol. 264; p. 116386
• Main Authors: Gümrükçü Köse, Gülşah, Keser Karaoğlan, Gülnur, Neccaroğlu Işık, Seher, Akyüz, Duygu, Koca, Atıf
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.06.2020; Elsevier BV
• Subjects: carboxyl; Chemical analysis; Chemical reduction; Electrochemical analysis; Electrochemistry; Electron transfer; Metal phthalocyanines; Metallography; NMR; Nuclear magnetic resonance; phthalocyanine; spectroelectrochemistry; Synthesis; unsymmetrical; phthalocyanine; carboxyl; spectroelectrochemistry; Synthesis; electrochemistry; unsymmetrical
• ISSN: 0379-6779; 1879-3290
• DOI: 10.1016/j.synthmet.2020.116386

Novel unsymmetrical A3B type 2,4-di-tert-butylphenoxy groups and 6-carboxy-2-naphthoxy substituted metal-free and metallo phthalocyanine derivatives were successfully synthesized by a statistical condensation reaction of the corresponding two phthalonitriles. The compounds were characterized by elemental analyses, FT-IR, 1H-NMR, UV–Vis and MALDI-TOF MS. Electrochemical and SEC measurements supported the proposed structures. The results indicated the usability of these complexes as functional materials due to their rich redox activities. Good photovoltaic performance of DSSC based on the ZnPc (3) indicated its possible usage in this field. [Display omitted] •Synthesis of unsymmetrically tetrasubstituted metallo and metal free phthalocyanines carrying one acid-terminated naphthoxy and three 2,4-di-tert-butylphenoxy groups.•Characterization of metal complexes by using spectroscopic techniques.•Electrochemical and spectroelectrochemical studies. In this study, novel A3B-type unsymmetrically tetrasubstituted metallo and metal free phthalocyanine compounds were synthesized by a statistical condensation method using two differently substituted precursors, 4-(6-carboxy-2-naphthoxy) phthalonitrile and 4-(2,4-di-tert-butylphenoxy) phthalonitrile. The structures of the synthesized phthalocyanine compounds (ZnPc, CuPc, CoPc, NiPc and H2Pc) were characterized with spectroscopic techniques of FT-IR, UV-Vis, 1H-NMR, MALDI-TOF MS and elemental analysis. Electrochemistry of metallophthalocyanines (MPcs) was studied and electrochemical responses were compared with each other in order to understand the influence of the cations in the Pc core and substituent environment to the redox responses of them. Electrochemical characterizations indicated that one metal based reduction and one metal based oxidization processes were observed with CoPc in addition to the Pc based electron transfer reactions. Moreover ZnPc, CuPc, NiPc, and H2Pc only indicated Pc ring based redox couples. Extraordinarily, all complexes were electrodeposited on the working electrode surface during the reduction reactions which intensively altered the redox behaviors of the complexes. In situ spectroelectrochemical characterizations supported the voltammetric assignments and indicated electrocheromic functionality of the complexes. ZnPc was tested as potential dye for DSSCs and illustrated reasonable photovoltaic performance.