Systems Containing Conjugated Spacers

In this section, the reactivity of carbon- and heteroatom-containing substituents attached directly or indirectly to the heterocyclic ring of 1,3-dithiole derivatives is discussed. Here, chemical manipulations on these systems exclude ring carbon and sulfur atoms, which are the subject of Section 4.12.6. Special 1,3-dithioles called Jt-extended TTFs, containing two or more 1,3-dithiole moieties linked together via =C-(C=C) -C= or similar conjugated spacers, are discussed with typical TTFs in Section 4.12.11, although formally they constitute an example of functionalization of the 1,3-dithiole by 2rt-extended substituents, terminated by another 1,3-dithiole moiety. 

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