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

3.6 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) was dried over sodium/benzophenone ketyl, acetyl chloride was
distilled over PCl 5 and triethyl amine over P 2 O 5 . The preparation of III-1 was carried out
according to the thesis of a previous student and sublimed prior to use. 1
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.
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-oxo-5H-naphtho[1,2-d][1,2,3]dithiazol-4-yl acetate (III-3). III-1 (0.2333 g, 0.9915
mmol) was dissolved in dry THF (30 mL) and an excess of triethylamine was added
(0.1452g, 1.435 mmol) to give a dark violet solution. After 15 minutes, a slight excess of
acetylchloride (0.1105 g, 1.408 mmol) was added to give a light orange reaction mixture
which was stirred at room temperature for 2 hours. A pale, off-white solid was filtered
and characterized to reveal that it was triethyl ammonium chloride. The dark orange
filtrate was evaporated under vacuum to give the title compound as a red powder
(0.1749 g, 0.6307 mmol) 64% yield based on III-1. Crystals suitable for X-ray
crystallography were grown by dynamic vacuum sublimation at 120 °C. ν max (KBr)/cm −1 :
3271(w), 1759(s), 1616(m), 1610(m), 1590(s), 1582(s), 1541(s), 1497(s), 1455(m),
124