30430-08-1Relevant academic research and scientific papers
1,1',2,2'-Tetrathiafulvalenes, II. - Thienothiophenes from 1,2-Dithiole Compounds; 3H-1,2-Dithiol-3-ylidenes (1,2-Dithiole-3-carbenes) as Supposed Intermediates
Behringer, Hans,Meinetsberger, Eike
, p. 1729 - 1750 (2007/10/02)
3,3'-Bi(3H-1,2-dithiolylidenes) (1,1',2,2'-Tetrathiafulvalenes) 5 are not obtainable with the following reactions which, however, have proved to be a good approach to the corresponding 1,3-isomers 3: 1) Deprotonation of 1,2-dithiolylium cations 4, 2) pyrolysis of alkali derivatives from 1,2-dithiol-2-one tosylhydrazones 26 (Bamford-Stevens reaction), or 3) partial desulfuration of 1,2-dithiole-3-thiones 6 by means of trivalent phosphorus compounds.These reactions with the 1,2-isomers always yield thienothiophenes 8 accompanied by the related 1,2-dithiole-3-thiones 6 (1,2-trithiones) and in the case of 26 also by azines 27.Partial desulfuration of 1,2-trithiones 6 by copper bronze again yields the corresponding thienothiophenes 8 instead of 5.Thermal decomposition of the 1,2-dithiolylium iodide 34 or 34' yields the thienothiophene 8a together with the 1,2-trithione 6a.Surprisingly, the P4S10-sulfuration of "desaurines" 37 gives thienothiophenes again and also 1,2-dithiole-3-thiones 6. - 1-Morpholinocyclohexene (18) reacts with the 1,2-dithiolylium cation 4a (X = ClO4) to give a formal 1:1 adduct from the carbene 9a and the enamine for which the structure 19 is proposed.
