With sulfur halides

The cyclic sulfur imides readily undergo condensation reactions in the presence of a base, e.g., pyridine. For example, the reaction of S7NH with sulfur halides, S Cla or SOCI2, produces the series (S7N)2Sx (x = 1, 2, 3, 5), or (S7N)2S0, respectively. The bicyclic compound S11N2 (6.6) is obtained by treatment of 1,3-S6(NH)2 with The reaction... 

Other examples of this synthetic strategy are known for example, a recent zirconium polymer by Illingsworth and Burke (8), who joined amine side groups of a zirconium bis(quadridentate Schiff-base) with an acid dianhydride to give amide linkages. Once again, caution is necesary, as Jones and Power (2) learned when they attempted to link metal bisO-diketonates) with sulfur halides that is, they obtained insoluble metal sulfides because the p-diketone complexes which they used were fairly labile and the insolubility drove the reactions to completion in the wrong direction. 

It is likely that thionitroso intermediates are involved in the formation of sulfurdiimides (RN=S=NR) by direct reaction of amines with sulfur halides, but this has not proved to be a synthetically useful route to RN=S species [78ZC323 84JCS(P1)2591 85PS277]. Three routes will be considered ... 

In addition, the first polythiazylphosphazenes (38), which contain two coordinate sulfur(III) atoms, were prepared from the reaction of Cl2PN2(SiMe3)3 with sulfur halides [50]. The materials, which also possess alternating S-N and P-N units in the polymer backbone, represent true hybrids of poly(sulfur nitrides) and polyphosphazenes and further developments in this area should prove to be particularly interesting ... 

We have also expanded our studies to include chromium(III) systems. However, for the chromium centers we have chosen the more volatile tri-fluoro (tfa") and hexafluoro (hfa ) derivatives of 2,4-pentanedione. Since the fluorinated derivatives are deactivated relative to the electrophilic attack used in these polymerizations, the Cr(acac)2(tfa) mixed ligand complex has been used initially to obtain polymeric products with sulfur halides. Whereas the intrinsic viscosity of one of the polymers so obtained was 0.17 dL/g, the GPC results suggest only oligomeric products. 

Also, unsaturated diimides can be reacted with sulfur halides to form polyimides ... 

Figure 5.27 Representative examples of NHC complexes with sulfur halides and oxides.

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