Thianthrene. structure

In this way it was established that both thiazone and thianthrene structures are present in all the quinoneimine sulfur dyes studied (C.L. Vat Blue 43, 53630 [1327-79-3] C.L Sulphur Black 6, 53295 [1327-16-8], C.l. Sulphur Black 7, 53300 [1327-17-9]-, C.L Sulphur Black 11, 53290 1327-14-6] and C.L. Sulphur Red 5, 53820). The thianthrene structure was also found to contribute greatly to the sub-stantivity of the dyes. 

A different approach leading to thianthrene derivatives starts from 0-ethyl or 0-isopropyl dithiocarbonate 394, when heated with chlorodinitrobenzene derivative 59 provided intermediate 395, the compound having all features necessary for denitrocyclization reaction to the final product 396, which was the only isolated compound (Scheme 61). Its structure was assigned by X-ray crystallography (77JOC2896). 

Figure 17. 1,4-Dithiin 21 and the molecular structure of its radical-cation salt 2f+SbF6 determined by X-ray crystallography. The observed lengths (A) of Cl-S and C1-C2 in 2f+SbF6 are 1.72(1) and 1.31(2) to be compared with 1.324(3) and 1.760(2) determined for neutral 21, respectively. Also shown is the thianthrene radical cation 23 +. 

Fluorescence was used to investigate the excited-state dynamics of the radical cation of thianthrene (TH ) <2001PCA6594>. The frequencies of the fundamental modes of the molecules of some dioxins in the ground electronic state were also determined by analysis of their fine-structure phosphorescence spectra <19990PS(86)239, 19970PS(83)92, 20000PS(89)42, 20000PS(88)339>. 

The proton spectra for the dibenzo derivatives, viz. dibenzo[6,e][l,4]dioxin, phenoxathiin and thianthrene, have been reported in full, as part of a wider survey of heterocyclic compounds structurally related to anthracene. The protons in dibenzo[6,e ][ 1,4]dioxin are the most shielded, and in phenoxathiin the protons ortho and para oriented to the C—O bond are shielded relative to those ortho and para to sulfur <740MR(6)U5). The 13C chemical shifts for phenoxathiin follow a similar pattern, with carbons ortho and para to the C—O bond resonating at 117.5 and 124.2 p.p.m. respectively, and at higher field than those ortho, para to the C—S bond (127.4 and 126.5 p.p.m.), in good agreement with shifts predicted on the basis of additivity effects <73JMR(12)143). 

The eadiest reported reference describing the synthesis ofphenylene sulfide structures is that of Friedel and Crafts in 1888 (6). The electrophilic reactions studied were based on reactions of benzene and various sulfur sources. These electrophilic substitution reactions were characterized by low yields (50—80%) of rather poorly characterized products by the standards of 1990s. Products contained many by-products, such as thianthrene. Results of self-condensation of thiophenol, catalyzed by aluminum chloride and sulfuric acid (7), were analogous to those of Friedel and Crafts. 

The first reported assignment of the PPS structure to reaction products prepared from benzene and sulfur in the presence of aluminum chloride was made by Genvresse in 1897 (8). These products were oligomeric and contained too much sulfur to be pure PPS. Genvresse isolated thianthrene and an amorphous, insoluble material that melted at 295°C. These early synthetic efforts have been reviewed (9—11). 

Many sulfur dyes contain benzothiazole, thiazone or thianthrene groups, and almost the whole range of shades can be obtained. The number of commercially available sulfur dyes is small but their production volume is large. Sulfur Black T with all conceivable variations may be the biggest synthetic dye which is used as a penetrating dye on leather Sulphur Black 1, 53185 [1326-82-5] (18 most probable structure). 

In addition, there is evidence that a class of compounds including thianthrene(II), phenoxathiin(VIIb) and phenoxazine(Vb) may be present in this coal. These compounds are thermally quite reactive and would probably not survive extended pyrolysis or liquefaction conditions. Instead, they will convert into the more stable dibenzothiophenes. This would suggest that chemical or biological removal of these compounds could be more efficient than a thermal process. Work is in progress to better characterize these structures by among other approaches HRMS/MS. 

Thianthrene (48) is one of the principal products of the action of sulfur chloride (or of sulfur) on benzene in the presence of aluminum chloride.68 Ariyan et al,69 similarly obtained the linear disulfide (49) by treating -diethoxybenzene with sulfur chloride in an inert solvent the structure was confirmed by X-ray diffraction.70... 

Peroxide complexes of molybdenum(VI) are intermediates in industrially important epoxidation reactions. The so-called Mimoun-type complexes [Mo 0(02)2LaxLeq]° " (12) generally exhibit pentagonal-bipyramidal structures, with an axial 0x0 group trans to Lax and Leq, and two peroxo groups in the equatorial plane. These complexes are effective reagents for the selective oxidation of alcohols to aldehydes, amines to nitroso compounds, sulfldes to sulfoxides and then to sulfones, phenols to o-quinones, and in the sulfoxidation of thianthrene-5-oxide. 

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