Dithiazolyl magnetism

Variable-temperature ESR studies have revealed large magnetic bistabilities in thiadiazole-fused 1,3,2-dithiazolyl 32 <2001SM1767, 2001MI451, 2002MI064434>, the thiadiazolopyrazine-fused 1,3,2-dithiazolyl 34, but not with the benzothiadiazolo-fused 1,3,2-dithiazolyl 33 <2004JA8256>. ESR studies have also been performed on inclusion crystals of the bicyclic [ 1,2,5]thiadiazolo[3,4-z/][ 1,3,2]dithiazol-2-yl 32 in channels of perhydrotriphenylene and tris(o-phenylenedioxy)cyclotriphosphazene <2002MI432>. 

Research in the reviewed period 1995-2005 has covered more the chemistry of 1,3,2-dithiazoles and less the chemistry of 1,3,2-dioxazoles. 1,3,2-Oxathiazoles and their derivatives were not investigated in this period. Much attention has been paid to the neutral 1,3,2-dithiazolyl radicals including their synthesis, theoretical and structural study, and application. Special attention was given to their magnetic properties and conductivity. 1,3,2-Benzodithiazole. Y-oxidcs were of interest as enantiomeric compounds and intermediates for the preparation of enantiopure amines and alcohols. 

The structures of compounds containing a 1,3,2-dithiazole ring (1,3,2-dithiazolidines, 1,3,2-dithiazoles, 1,3,2-dithia-zolium cations and radicals) were extensively investigated by X-ray and electron diffraction between 1980 and 1990 <1996CHEC-II(4)433>. Nuclear magnetic resonance (NMR) spectroscopy was found to be very effective for elucidation of the structure of 1,3,2-dioxazoles and 1,3,2-dithiazoles. Electron spin resonance (ESR) spectra of the 1,3,2-dithiazolyl radicals gave important information on their structures. 

Preparation, crystal structures, and magnetic properties of 3-cyanobenzo-l,3,2-dithiazolyl radical were recently reported <2006IC1903>. The crystal structure and magnetic properties of thiazyl radicals and related materials have been reviewed <2006BCJ25>. 

Chung Y-L, Fairhurst SA, Gillies DG, et al. (1992) ESR spectroscopy of some dicyano-, pyrazino- and quinoxa-lino-l,3,2-dithiazolyl radicals. Magnetic Resonance Chemistry 30 774—778. 

EPR and computational studies on 1,3,2-dithiazolyls suggest an almost zero dimerization enthalpy indicating that they are mosdy monomeric in the solid state (1987CC66, 2000JCD3365). For this reason, 1,3,2-dithiazolyls exhibit a variety of sohd-state packing patterns associated with exotic magnetic properties. Furthermore, these radicals are often stable in solution and in the solid state with low reactivity to air. 

Resonance-stabilized 1,2,3-dithiazolyls form TT-shpped stacks and show modest conductivity but with magnetically ordered phases. The... 

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