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

the two manganese centers to have the same spin-vector orientation as well, as has been
observed for compounds II-6 and II-9.
Figure 2-15. Chain formation of theoretical manganese complex of II-15.
Some effort has been put toward the isolation of the binuclear coordination complex
of II-15, however there were several challenges associated with it.
The strong
association of the radical with itself in the solid state translated to poor solubility and
refluxing conditions were required to achieve complete homogeneity of the radical
solution prior to the addition of the metal starting material.
A colour change was
observed when the metal containing starting material was introduced, but sublimation of
the resulting residue provided only a very small amount of amorphous powder and was
not enough for elemental analysis. It may be possible to explore alternative crystallization
techniques, but the high solubility of these complexes imparted by the hfac ligands makes
solution methods very challenging. There is the possibility that acac ligands could be
used in their stead, but other than the fact that this might have too dramatic an effect on
the packing tendency of the complexes, the highly electronegative nature of the ancillary
hfac ligands prevents the formation of S-M bonds discussed near the end of chapter 1,
which could potentially destroy the radical character of the ligand.
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