Radical anions containing the dioxidated 1,2,5-thiadiazole heterocycle

M. V. MIRIFICO; J. A. CARAM; C.J. COBOS; A. M. GENNARO; E. J. VASINI

JOURNAL OF PHYSICAL ORGANIC CHEMISTRY

JOHN WILEY & SONS LTD

Año: 2009 vol. 22 p. 964 - 970

0894-3230

Radical anions of 3,4-aryl disubstituted 1,2,5-thiadiazole 1,1-dioxide have beenobtained by chemical and by electrochemical reduction of their substrates, andcharacterized by ESR spectroscopy and cyclic voltammetry. The radical anion of thephenanthro[9,10-c]-1,2,5-thiadiazole 1,1-dioxide was found to be very stable in aproticsolvent solution and did not react readily when water was added to the aprotic solvent,or the solution was saturated with oxygen gas. The radical formation chemical reactioncompeted with nucleophilic addition to the C=N bond of the thiadiazoles. A possiblereaction mechanism, and a common reaction intermediate, supported by densityfunctional theory calculations is presented for the most stable radical.