Diazafulvalene

Abstract

DiazafulvalenesCondensation of sodium cyclopentadienid (10) with the pyrazolium salts 6 and 9 leads to formation of 2,3-diazafulvalenes lla,b. Oxidation of 1methyl-3.5-bis(methyIthio)py~ole (8) with KHSO5 yields bissulfone 12, subsequent methylation affords the pyrazolium salt 13. This condenses with 10 lo give the sodium salt 14.