The Synthesis and Characterization of Stable Radicals Containing the Thiazyl (SN) Fragment and Their Use as Building Blocks for Advanced Functional Materials - Stable Radicals: Fundamentals and Applied Aspects of Odd-Electron Compounds - page 339

2e −

S N S N S N

∆

N

N S e − N S e − N S

S

NC

S N S N S N

S

N S N S N S

N

56 57 59 60

fast

N N

N N

S
S

S
N

S
S

S
N

N S

N S

61

58

N N

S
S

S
S

N N

39

Scheme 9.16

Figure9.12 X-raycrystalstructureof(NSSNC)-(CNSNS) 61 . 115,151

The mixed diradical ultimately isomerizes to the bis(1,2,3,5) diradical 39 , which had been independently
synthesized. 121 Two-electron reduction of the dication 56 gives the bis(1,3,2,4) diradical 59 , which has not
been structurally characterized. Attempted sublimation causes 59 to decompose to (among other things)
the cyano-substituted-1,2,3,5-dithiadiazolyl 60 . 108 High level computational studies indicate that 59 108

and

61 115 are, like 39 , 104 biradical in nature with very weakly interacting spins.

9.3.4 1,3,2-Dithiazolyl radicals

The 1,3,2-dithiazolyl radical system also dates back to the 1970s; the benzannelated subset of these
radicals 65 was reviewed by Rawson in 2000. 152 1,3,2-Dithiazolyls were originally spectroscopically