Experimental evidence for long-range stabilizing and destabilizing interactions between charge and radical sites in distonic ions

External electric field effects on chemical structure and reactivity

“…3 By carefully positioning charged functional groups attached to one of the reactants, a catalyst or an auxiliary compound involved in the reaction, a short-range electric field aligned with the targeted reaction-or bond-axis can be produced. 14 One of the virtues of this technique is that careful design can even lead to switchable catalysis whereby the LEF can be turned on and off with the help of external stimuli. In this regard, Coote and coworkers 12,13 focused mainly on pH-switchable D-LEFs and demonstrated among others that bond-dissociation energies (BDEs) can be effectively tuned with the help of the electrostatic field resulting from protonation/deprotonation of a distant (though sufficiently close) acidic/basic group.…”

“…Probably the most promising experimental technique from a practical perspective developed so far is the D‐LEF approach . By carefully positioning charged functional groups attached to one of the reactants, a catalyst or an auxiliary compound involved in the reaction, a short‐range electric field aligned with the targeted reaction‐ or bond‐axis can be produced . One of the virtues of this technique is that careful design can even lead to switchable catalysis whereby the LEF can be turned on and off with the help of external stimuli.…”

“…Since these initial experiments, several interesting alternative strategies have been proposed, ranging from interfacial electric fields (IEFs) 2,[6][7][8][9][10][11] to designed local electric fields (D-LEF), for example, by pH-switchable charges. [12][13][14] Even though these techniques constitute advances on the road toward a more practical implementation of EEFs in chemical synthesis, the main challenge lying ahead on the experimental front remains the development of a truly scalable technique, enabling the alignment of the electric field with the desired reaction-or bond-axes, which could be employed in an industrial setting.…”

“…While such an STM setup enabled the unequivocal verification of the catalytic effect of the oriented external electric field (OEEF), this technique is less realistic from a practical synthetic perspective due to obvious scalability issues (vide infra). Since these initial experiments, several interesting alternative strategies have been proposed, ranging from interfacial electric fields (IEFs) to designed local electric fields (D‐LEF), for example, by pH‐switchable charges . Even though these techniques constitute advances on the road toward a more practical implementation of EEFs in chemical synthesis, the main challenge lying ahead on the experimental front remains the development of a truly scalable technique, enabling the alignment of the electric field with the desired reaction‐ or bond‐axes, which could be employed in an industrial setting.…”

Electrostatically Tuning the Photodissociation of the Irgacure 2959 Photoinitiator in the Gas Phase by Cation Binding

“…[23][24][25][26][27][28][29][30][31] PD action spectroscopy of ions complements other experimental strategies examining the effect of electric fields on molecular reactivity. 8,[32][33][34][35][36][37][38] This paper focuses on the photodissociation of Irgacure 2959 (Irg), 2-hydroxy-4-(2-hydroxyethoxy)-2methylpropiophenone, a well-known photoinitiator based on acetophenone with Norrish type-I photo-chemistry 9, 10 and popular for use in bio-printing. [39][40][41] Irg absorbs in the UV region with an absorption maximum at l = 273 nm.…”