The equilibrium and kinetics of intermolecular hydrogen bonding in nitroarene anion radical–alcohol system: 1,3‐dinitro‐benzene anion radical – R–OH (R═CH₃–, C₂H₅–, (CH₃)₂ CH–)

Abstract

To explore the possibility of hydrogen bonding of a stable anion radical with DNAcomponent sugar, hormones, steroid, and so on (through hydroxyl group), as a first step, the possibility of hydrogen bonding of 1,3-dinitrobenzene anion radical (1,3-DNB À• ) with aliphatic alcohols was studied. It was found that 1,3-DNB À• anion radical undergoes hydrogen bonding with alcohols: methanol, ethanol, and 2-proponal. The hydrogen-bonding equilibrium constant K eq and the (hydrogen-bonding) rate constants k 2 were evaluated through the use of linear scan and cyclic voltammetry theory and techniques. The K eq was found to be in the range of 1.4-6.0 M À1 , whereas the rate constants k 2 were found to be in the range of 1.5-3.6 M À1 s À1 , depending upon the hydrogen-bonding agent and the equation used for the calculation of the rate constants. The hydrogen-bonding number n was found to be around 0.5 or 1.0. The implication of this study in, for example, the replication of DNA, the prevention of the formation of super oxide, and so on is discussed.

Coherent Anti-Stokes Raman Scattering Microspectroscopic Kinetic Study of Fast Hydrogen Bond Formation in Microfluidic Devices

“…28 This is especially important in view of the significant differences in the formation rates of different types of simple supramolecular components obtained by the above-mentioned "invasive" methods (>10 6 M −1 s −1 ) 21,29−31 in comparison with electrochemical and gravimetric tools (<10 M −1 s −1 ). 32,33 Here, we show that quantitative coherent anti-stokes Raman scattering (CARS) microspectroscopy, 34−40 a label-free imaging technique used in a microfluidic device, 41 is an interesting platform to interrogate H-bond kinetics without strong influence of the measuring technique on the interaction. This is achieved by the excitation of submicrometer areas of steadily flowing species in the course of CARS measurements, which does not influence the overall interaction behavior.…”