1,2,3-Dithiazolyl and 1,2,35-Dithiadiazolyl Radicals as Spin-Bearing ...

5.5 Experimental
General
All reactions and manipulations were performed under an argon atmosphere using
standard Schlenk techniques. Solvents were dried and distilled under argon prior to use:
tetrahydrofuran (THF) dried over sodium/benzophenone ketyl; methylene chloride dried
over CaH 2 ; acetonitrile dried over P 2 O 5 . All acids were purchased from Fisher and used
as received. 1,2-Napthaquinone was purchased from Acros and used as received.
Triphenyl antimony was purchased from Aldrich and recrystallized from acetonitrile
prior to use. Nitrosyl hexaflurophosphate was purchased from Acros and sublimed prior
to use. 5-Chlorobenzo[c][1,2,5]thiadiazol-4-amine was purchased from TCI America and
used as received. All other reagents were purchased from Aldrich and used as received.
IR spectra were recorded as pressed KBr pellets on a Nicolet 510-FTIR spectrometer at
ambient temperature. Elemental analyses were performed at MHW Laboratories,
Phoenix, A . Electron paramagnetic resonance (EPR) spectra were recorded on a Br ker
EMX spectrometer. Electrochemical measurements were obtained at ambient temperature
using an Autolab PGSTAT 30 instrument and a three-electrode (platinum) glass cell,
sealed under an argon atmosphere.
5-Chloro-1H-[1,2,5]thiadiazolo[3,4-e][1,2,3]benzodithiazolium chloride (V-3). Sulfur
monochloride (11.942 g, 88.440 mmol) was added to a homogeneous solution of 5-
chlorobenzo[c][1,2,5]thiadiazol-4-amine (2.0155 g, 10.998 mmol) in distilled and
degassed acetonitrile (60 mL). A thick, orange precipitate was formed immediately and
over the next hour the solution turned to a brown, heterogeneous mixture. The reaction
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