0000000000320136
AUTHOR
Yan Cui
Electrochemical and Spectroelectrochemical Properties of Free-Base Pyridyl- and N -Alkyl-4-Pyridylporphyrins in Nonaqueous Media
International audience; Twelve structurally related pyridyl and meso-N-methylpyridylporphyrin derivatives are investigated electrochemically in different nonaqueous media. The UV/Vis spectrum of each newly investigated porphyrin was measured before and after electro-reduction and, based on this data, the site of electron transfer is proposed. An interaction occurs between the meso-pyridyl or meso-N-alkyl-4-pyridyl substituents and the porphyrin p-ring system, the magnitude of which depends upon the number of linked pyridyl or N-alkyl-4-pyridyl groups in the compound, the solvent, the supporting electrolyte, and/or other anions added to the solution.
Non-linear optical, electrochemical and spectroelectrochemical properties of amphiphilic inner salt porphyrinic systems
Three zwitterionic meso-substituted A3B- and AB2C-porphyrins containing one sulfonato alkylpyridinium substituent and three or two alkoxy-substituted phenyl groups were synthesized in good yield and fully characterized as to their physicochemical properties by a variety of techniques. This new series of inner salt donor-acceptor meso-substituted porphyrin derivatives were prepared for possible application as amphiphilic probes for membrane insertion in the area of combined second-harmonic and two-photon fluorescence cellular microscopy. To this end, the linear and nonlinear optical properties of the compounds were characterized, together with their electrochemical and spectroelectrochemica…
Tuning the Electrochemistry of Free-Base Porphyrins in Acidic Nonaqueous Media: Influence of Solvent, Supporting Electrolyte, and Ring Substituents
International audience; A detailed study of reduction potentials, electroreduction mechanisms and acid-base chemistry was carried out on two series of free-base porphyrins in nonaqueous media. The first series is represented by four-pyrrole substituted tetraphenylporphyrin (TPP) derivatives, two of which are planar and two of which are nonplanar in their non-protonated form. The second comprises porphyrins with 0-4 meso-phenyl groups on the macrocycle. Equilibrium constants for conversion of each neutral porphyrin to its diprotic [H4P] 2+ form were determined and the electrochemistry was then elucidated as a function of: (i) type of nonaqueous solvent, (ii) anion of supporting electrolyte, …
Tetracationic and Tetraanionic Manganese Porphyrins: Electrochemical and Spectroelectrochemical Characterization
International audience; The electrochemistry and spectroelectrochemistry of four tetrapositively charged and two tetranegatively charged porphyrins were characterized in two nonaqueous solvents (dimethyl sulfoxide and N,N-dimethylformamide) containing 0.1 M tetra-n-butylammonium perchlorate. The tetrapositively charged compounds are represented by the tetrapyridylporphyrins [TRPyPM]4+(X-)4, where R is a methyl or [2-[2-(2-methoxy)ethoxy]ethoxy]ethyl group, M = MnIIII, MnIIICl, CuII, or PdII, and X = I- or Cl-. The tetranegatively charged porphyrins are represented by the tetrasulfonato derivatives [TPPSMn(OAc)]4-(NH4+)4 and [TArPSMn(OAc)]4-(NH4+)4, where Ar = 4-O-[2-[2-(2-methoxy)ethoxy]eth…
Protonation and Electrochemical Properties of Pyridyl- and Sulfonatophenyl-Substituted Porphyrins in Nonaqueous Media
International audience; The protonation and electrochemical properties of positively charged and negatively charged porphyrins are reported in up to five different nonaqueous solvents. The positively charged porphyrins are represented by mono- and di-pyridyl derivatives having the formula Pyx(PhMe)4-xPM, where P=the dianion of the porphyrin macrocycle, PhMe is a meso-tolyl group, Py a meso-pyridyl group, x=1 or 2, and M=H2, NiII, CuII, ZnII, or CoII. The negatively charged porphyrins are comprised of meso-tetrasulfonato derivatives having the formula [(R)4(TPPS)H2]4−(X+)4, where [(TPPS)H2]4− represents the porphyrin with four SO3− groups on the meso-phenyl substituents of the macrocycle, R=…