Reactivity of 1,3,2,4-Dithiadiazolyls

As previously mentioned, the spin-paired and radical species (3 and 3 ) exhibit significantly different chemistries, and this is highlighted in their differing physical properties such as their esr behavior (Section XVIII.A). This difference is carried through to their reactivities, and so their chemical properties will be described separately. 

Since these materials (Table XIII) are usually unstable, their chemistry has primarily been limited to rearrangement and polymerization reactions. 

The solution-state rearrangement can be conveniently monitored by esr a three-line 1 1 1 triplet (Section XVIII.A) is replaced over a period 

Although some of the thermally stable derivatives of 3 (e.g., /Bu) can be isolated in a pure state (if kept in the dark) (87CC69), other radicals, particularly 3 (R = Me, I), form intractable brown polymers at high concentrations ( 1 molal). The nature of such polymeric materials is unknown. 

Unlike 3, spin-paired derivatives 3 show no tendency to undergo rearrangement in solution (or even on heating in the solid state [92JCS(D)1277] see the diradicals described in Section XXIII.G.3). In fact, such materials appear significantly more stable and their chemistries more diverse. 

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