Tetrasulfur dinitride

S4N2 forms dark red needles (mp 23°C) upon recrystallization from diethyl ether. It sublimes readily at room temperature, but must be stored at -20°C to avoid decomposition. Several routes are available for the preparation of S4N2. The decomposition of Hg(S7N)2 at room temperature gives the best yield, while the reaction of S2CI2 with aqueous ammonia is quick, cheap and provides a purer product. 

The heat of formation of 804X4 was determined to be AH°f = +163 kcal mor. Thus 804X4 is even more endothermic than S4X4 (AH°f = +110 kcal mok ). The mean E-X bond energies in E4X4 were estimated to be 59 kcal mol (E = Se) and 72 kcal mol (E = S) from the enthalpies of formation. 

Rietveld analysis indicates that S4N4 undergoes a transition to a new 

The reactions of S4N4 with alkynes have also been investigated in considerable detail. These reactions produce 1,3,5,2,4-trithiadiazepines (5.9) and 1,3,5,2,4,6-trithiatriazepines (5.10), both of which are planar, ten r-electron seven-membered rings (Section 12.3), but the major products are 1,2,5-thiadiazoles.  

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Tetrasulfur dinitride can be prepared by (a) treatment of [(Me3Si)2N]2S with equimolar amounts of SC12 and S2C12,48 (b) the reaction of the trisulfane S3[N(SiMe3)2]2 with a mixture of S2C12 and S0C12,49 (c) the decomposition of... 

Tetratellurium tetranitride, 4773 Tetrasulfur dinitride, 4755 Tetrasulfur tetranitride, 4770 Thallium(I) nitride, 4731... 

The Trisulfur Trinitride Anion, SjN, and Tetrasulfur Dinitride, S4N2 124... 

Structurally characterized since 1970 and the structure of the eighth (S4N3 ) has been redetermined recently b) the first binary sulfur-nitrogen anion, S N " was isolated in 1975 and its structure was reported a year later c) the novel sulfur nitride, SjNg, was first identified in 1978 and d) although tetrasulfur dinitride, S N, has been known since 1897, the structure was not unequivocally determined until 1981... 

Tetrasulfur dinitride S4N2 readily reacts with ethynes in various organic solvents to give 1,3,2-dithiazolyl stable radicals (58) <87CC66, 83JCS(Fl)925>. 

Tetraselenium tetranitride, 4765 Tetrasulfur dinitride, 4750 Tetrasulfur tetranitride, 4764... 

The following procedures give the synthesis of tetrasulfur tetranitride, disulfur dinitride, polymeric sulfur nitride, and tetrasulfur dinitride. 

As with the preparation of tetrasulfur tetranitride, caution must be observed tetrasulfur dinitride decomposes explosively at temperatures of ca. 30°, and on grinding with only slight pressure very violent detonations can occur. It should also be noted that at room temperature the substance undergoes appreciable polymerization in a short time. 

This compound is prepared by the reaction of tetrasulfur tetranitride with sulfur. An autoclave, fitted with a magnetic stirrer and capable of being heated to 100°, is used as the reaction vessel. A mixture of 24 g. of tetrasulfur tetranitride and 50 g. of sulfur is suspended or, respectively, dissolved in 380 ml. of pure carbon disulfide. The mixture is heated in the autoclave for 2 hours at 110° and then cooled rapidly. It is then filtered from the polythiocyanogen which is formed under these conditions, and the residue washed well with carbon disulfide. These washings are added to the original filtrate, and this is then evaporated in vacuum. The red residue after removal of carbon disulfide is distilled in high vacuum with a bath temperature of 60 to 65°, whereupon dark red crystals separate in the receiver (f.p. 23°). It is found that the best yields are obtained when the walls of the autoclave are soiled from a previous preparation, in which case about 4 g. of tetrasulfur dinitride is usual. 

Tetrasulfur dinitride, 6 128 Tetrasulfur tetranitride, 6 124 5-Tetrazolediazonium sulfate for preparation of tetrazolone, 6 64 Tetrazolone, 6 62 1,2,3,4-Thiatriazole, 5-amino and 5-(substituted)amino derivatives, 6 42, 44... 

N2S4 Tetrasulfur dinitride, 6 128 N3CS2H Azidodithiocarbonic acid, 1 81, 82... 

S4N2 Tetrasulfur dinitride, 6 128 S4N4 Tetrasulfur tetranitride, 6 124... 

The reaction of tetrasulfur dinitride with norbomadiene produced a 1 1 cycloaddition adduct (257) (mp 92-94 °C, A ax 266, 362, 420 nm) as orange crystals in 12% yield (Equation (60)). This reaction represents a forbidden [2, + 2J process. However, the observation of free radicals in similar reactions suggests that a nonconcerted diradical mechanism is involved <83CJC1185>. 

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