Electrochemical and chemical reduction of disulfur dinitride: formation of [S4N4], EPR spectroscopic characterization of the [S2N2H]• radical and X-ray structure of [Na(15 crown-5)][S3N3]

Roemmele, Tracey L.; Konu, Jari; Boeré, René T.; Chivers, Tristram

Electrochemical and chemical reduction of disulfur dinitride: formation of [S4N4], EPR spectroscopic characterization of the [S2N2H]• radical and X-ray structure of [Na(15 crown-5)][S3N3]

dc.contributor.author	Roemmele, Tracey L.
dc.contributor.author	Konu, Jari
dc.contributor.author	Boeré, René T.
dc.contributor.author	Chivers, Tristram
dc.date.accessioned	2019-03-29T22:55:59Z
dc.date.available	2019-03-29T22:55:59Z
dc.date.issued	2009
dc.description	Sherpa Romeo white journal. This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher.	en_US
dc.description.abstract	Voltammetric studies of S2N2 employing both cyclic voltammetry (CV) and rotating disc electrode (RDE) methods on GC electrodes at RT revealed two irreversible reduction processes at ca. −1.4 V and −2.2 V in CH3CN, CH2Cl2 and THF (vs. ferrocene) and no observable oxidation processes up to the solvent limit when the scan is initially anodic. However, after cycling the potential through −1.4 V, two new couples appear near −0.3 V and −1.0 V due to [S3N3]−/0 and [S4N4]−/0 respectively. The diffusion coefficient D for S2N2 was determined to be 9.13 × 10−6 cm2 s−1 in CH2Cl2 and 7.65 × 10−6 cm2 s−1 in CH3CN. Digital modeling of CVs fits well to a mechanism in which [S2N2]−• couples rapidly with S2N2 to form [S4N4]−•, which then decomposes to [S3N3]−. In situ EPR spectroelectrochemical studies of S2N2 in both CH2Cl2 and CH3CN resulted in the detection of strong EPR signals from [S4N4]−• when electrolysis is conducted at −1.4 V; at more negative voltages, spectra from transient adsorbed radicals are observed. In moist solvent or with added HBF4, a longer-lived spectrum is obtained due to the neutral radical [S2N2H]•, identified by simulation of the EPR spectrum and DFT calculations. The chemical reduction of S2N2 with Na[C10H8] or Na[Ph2CO] produces [Na(15-crown5)][S3N3], while reduction with cobaltocene gives [Cp2Co][S3N3]. The X-ray structure of the former reveals a strong interaction (Na···N = 2.388(5) Å) between the crown ether-encapsulated Na+ cation and one of the nitrogen atoms of the essentially planar six-membered cyclic anion [S3N3]−.	en_US
dc.description.peer-review	Yes	en_US
dc.identifier.citation	Roemmele, T. L., Konu, J., Boeré, R. T., & Chivers, T. (2009). Electrochemical and chemical reduction of disulfur dinitride: Formation of [S4N4], EPR spectroscopic characterization of the [S2N2H]• radical, and X-ray structure of [Na(15 crown-5)][S3N3]. Inorganic Chemistry, 48(19), 9454–9462. doi:10.1021/ic9014114	en_US
dc.identifier.uri	https://hdl.handle.net/10133/5304
dc.language.iso	en_US	en_US
dc.publisher	ACS Publications	en_US
dc.publisher.department	Department of Chemistry and Biochemistry	en_US
dc.publisher.faculty	Arts and Science	en_US
dc.publisher.institution	University of Lethbridge	en_US
dc.publisher.institution	University of Calgary	en_US
dc.publisher.url	https://doi.org/10.1021/ic9014114
dc.subject	Electrochemistry	en_US
dc.subject	Chemical reduction	en_US
dc.subject	Disulfur dinitride	en_US
dc.subject	EPR spectroscopy	en_US
dc.subject	DFT calculations	en_US
dc.subject.lcsh	Reduction (Chemistry)
dc.subject.lcsh	Radicals (Chemistry)
dc.subject.lcsh	Voltammetry
dc.subject.lcsh	Electron paramagnetic resonance spectroscopy
dc.title	Electrochemical and chemical reduction of disulfur dinitride: formation of [S4N4], EPR spectroscopic characterization of the [S2N2H]• radical and X-ray structure of [Na(15 crown-5)][S3N3]	en_US
dc.type	Article	en_US