Triradicals Zimmermann triradical

Zimmermann triradical 24 makes a reasonable case for the S — 3/2 state (Fig. 2), especially in view of the characterization tools and techniques available up to the mid-1970s. From the 2005 perspective, monomeric triradical 24 with S — 3/2 state was probably a very minor component in solution, i.e., 24 was largely oligomerized and it was likely to contain significant amounts of impurity diradicals and monoradicals... 

Leo triradical (a) Leo, M. (1937). Uber radical emit mehreren dreiwertigen kohlenstof-fatomen. Chem. Ber. 70, 1691-1694 (b) Wilker, W., Kothe, G. and Zimmermann, H. (1975). Uber da radical l,3,5-benzoltris(diphenylmethyl). Tetramere und quartettzu-stand. Chem. Ber. 108, 2124-2136... 

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