On the oxidation of Wurster’s reagent and the Wurster’s crown analog of 15-crown-5 in the presence of alkali metal cations

Electrochemistry of the sterically hindered imidazolidine zwitterion and its paramagnetic derivative

“…By combining electrochemical methods with a spectroscopy [15], one can gain additional information about the electrode processes, electronic structure, geometry, and reactivity of depolarizers [16,17]. We used the combined cyclic voltammetry and ESR method to investigate the redox properties of the stable paramagnetic anion 4,4,5,5-tetramethyl-2-oxoimidazolidine-3-oxide-1-olate (1 ÅÀ ) and 4,4,5,5-tetramethyl-1,2-dioxoimidazolidin-1-ium-3-olate (2).…”

A Redox-Gated Slow-Fast-Stop Molecular Rotor

“…Thus, the redox waves could be attributed to two single-electron transfer processes that form stable radical cation 1 +• and dication 1 2+ . The difference in the two oxidation potentials (Δ E = 0.15 V) is much smaller than that of Wurster’s Blue (Δ E = 0.59 V) , or N,N ′-diphenyl- p -phenylenediamine (Δ E = 0.53 V), indicating weak interactions between redox sites. This is consistent with the twisted PPD moiety in 1 predicted by DFT calculations (Figure S1).…”

“…p -Phenylenediamines (PPD) are a class of redox-active materials that undergo two-step oxidations to form the corresponding radical cation and dication species (Scheme ). The unusual stability of PPD radical cations (e.g., Wurster’s Blue) has attracted much attention, and their intriguing electronic properties such as magnetic susceptibility, high-spin activity, electron and energy transfer behavior, fluorescence, and electrostatic interactions have been reported. Nevertheless, the potential application of PPD in forming redox-gated molecular devices has not yet been demonstrated.…”

On the nature of the photochemical reaction of polypyridyl Ru(ii) complexes leading to sunlight-to-chemical energy conversion: density functional analysis

“…In our work the B3LYP hybrid functional 29,30 was employed in both DFT 31,32 and TD-DFT 33,34 calculations for the ground and excited states, respectively, using the Gaussian09 suite of program. 35 We employed the 3-21G basis set 36 (hereafter, the Basis-1), which is the all-electron basis set including the Ru atom, as well as the more extensive basis set, namely, the MWB28 ECP and (6s,5p,3d,1f) basis for Ru 37,38 and the 6-31+G(d,p) 39 basis for all other elements (hereafter, the Basis-2).…”