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Abstract The synthesis, characterization, and redox behavior of aryloxide complexes containing an increasing number of internal hydrogen bonds (OEP)Ru(NO)(OAr_xH) (OEP=octaethylporphyrinato dianion; x=0, 1, 2) are reported. These nitrosyl aryloxide compounds were characterized by X‐ray crystallography, IR and¹H NMR spectroscopy. The IR spectra displayed υ_NOfrequencies in the 1823–1843 cm⁻¹range with compounds possessing more internal hydrogen bonds demonstrating higher υ_NOfrequencies due to diminished π‐backdonation to the Ru−NO fragment. Comparison of the distinct υ_NHand δ_N−Hsignals in the IR and¹H NMR spectra of the free and complexed OAr_1H/OAr_2Hligands support the notion of additional electron density being removed via intramolecular hydrogen bonding. Results of DFT calculations on the (porphine)Ru(NO)(OAr_xH) models (porphine=unsubstituted porphyrin) reveal that the HOMOs of these complexes have significant axial ligand contributions, whereas the HOMOs of the five‐coordinate [(porphine)RuNO)]⁺cation resides mostly on the equatorial porphyrin macrocycle. The electrochemical results of these (OEP)Ru(NO)(OAr_xH) complexes in CH₂Cl₂reveal first oxidations that occur at increasingly positive potentials when more internal hydrogen bonds are present. Based on the DFT and preliminary IR spectroelectrochemical results, we propose that the electrooxidations result in eventual dissociation of the axial aryloxide ligands.