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

provide a dry, dark, free-flowing residue (crude yields tended to be quite greater than
90%) which is then placed on a gradient tube furnace to give a purified crystalline sample
of the target species by sublimation in preparative quantities. The purified yields were
usually on the order of 35-45%. This is quite remarkable considering that the molecular
weight of the species investigated exceed 1000 g/mol. The high volatility of these
complexes can be attributed to the nature of the ancillary hfac ligands.
Scheme 2-2. Reaction sheme illustrating coordination of II-1 to give II-5; M = Ni and II-6; M = Mn..
This synthesis was successfully achieved for the nickel and manganese ions as
outlined in scheme 2-2. An analogous synthesis was attempted using cobalt, however X-
ray quality crystals suitable for structural analysis were not obtained. It is believed that
the compound thermally decomposed before the temperature for sublimation was
achieved at the reduced pressure. While several attempts at sublimation gave very low
yields of micro-crystalline material, we were never able to obtain enough for
characterization. Solution recrystallization was not considered due to the fact that the
high solubility of the metal-hfac species tends to be quite high and do not easily
precipitate from solution.
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