The Generation of Organic Radical Cations: A Guide to Current Practice for EPR Spectroscopic Studies

Abstract

A wide variety of methods is now available, each with its particular advantages and disadvantages, for generating radical cations for EPR or other spectroscopic studies in fluid solution or in matrix. This field is critically surveyed, together with recent developments in the understanding of the mechanisms of these reactions.

An Efficient Synthesis of a Highly Functionalized Dihydrobenzo­thiophene Derivative: A Ring-Contracted Analogue of the Anti-inflammatory Drug Propoxicam

“…This unleashed a domino process comprising the N-Boc and the S-PMB groups deprotection and, concomitantly, the desired cyclization via C-S bond formation to generate the benzothiophene ring of compound 1, 15 presumably by a radical mechanism initiated by Hg(II)-promoted formation of a cation radical on the sulphur atom of 10. 16 The structure of 1 was confirmed by high-resolution mass spectral data and by the presence of the two carbonyls both in the IR and 13 C-NMR spectra, together with a quaternary carbon at ca. 90 ppm that corresponds to the C-2 quaternary carbon of the benzothiophene ring.…”

Biologically Relevant Small Radicals

“…Oxidations and reductions can be performed by several chemical and electrochemical methods. [70,71] As an example, the one-electron reduction of the helianthrone derivative (1, Fig. 4) gives [72] the EPR spectrum displayed in Fig.…”