Synthesis and spectral and thermal characterization of new metal-free and metallophthalocyanines: investigation of their photophysical, photochemical, and thin film properties

Abstract

Novel tetrasubstituted metal-free (2), zinc (II) (3), cobalt (II) (4), and copper (II) (5) phthalocyanines bearing 2-phenylethanolate groups on the peripheral positions were synthesized by the cyclotetramerization reaction of the phthalonitrile derivative 1. The new compounds were characterized by a combination of IR, 1 H NMR, 13 C NMR, UV-Vis, elemental analysis, and MS spectra data. The thermal stabilities of the phthalocyanine compounds were determined by thermogravimetric analysis. For metal-free (2) and zinc (3) phthalocyanines, photochemical (photodegradation and singlet oxygen quantum yields) and photophysical (fluorescence quantum yields and fluorescence lifetimes) properties were analyzed in dimethylsulfoxide (DMSO). The cobalt (4) and copper (5) phthalocyanines were not evaluated for this purpose because of their paramagnetic behavior. The metal-free (2) and zinc (3) phthalocyanines' fluorescence quenching behaviors were also investigated. The new phthalocyanine compounds' fluorescence emissions were effectively quenched by 1,4-benzoquinone in DMSO. The thin films of the cobalt phthalocyanine compound (4) were grown by electron beam evaporation technique. Crystalline CoPc (4) thin films were investigated by X-ray diffraction spectroscopy. Surface morphology of the CoPc (4) thin films was characterized by SEM.

Nanomaterials Based on Fe3O4 and Phthalocyanines Derived from Cashew Nut Shell Liquid

“…The difference between the fluorescence intensities of the Pc and ZnPc was due to influence of axial metal coordinated to the center of macrocycle. It is important to note that emission corresponding in this spectral region was not observed for other compounds (NiPc, CoPc and CuPc), due to paramagnetic behavior of central metals in the phthalocyanine cavity [39].…”

In Vivo Photodynamic Therapy With a Lipophilic Zinc(II) Phthalocyanine Inhibits Colorectal Cancer and Induces a Th1/CD8 Antitumor Immune Response

“…This family of dyes is also recognized for its high thermal stability. Thus, for substituted Pcs the initial degradation temperature is between 200 and 350°C [13]. On the contrary, Pcs are synthesized through a not laborious technique and without requiring many intermediaries.…”

Enhanced nonlinear optical responses of zinc diaminopyrimidin-2-ylthio phthalocyanine conjugated to AgxAuy alloy nanoparticles

“…Both the Pc and the conjugates were excited at the same wavelength (612 nm). The proximity of the wavelength of the Q band maxima absorption to the excitation Q band spectrum suggests that the excited state and the ground state of the molecule have similar molecular geometries[40]. The emission spectra in all cases (2-Ag 1 Au 3 as a representative) are up to 10 nm red shifted from absorption spectra.…”