Thiazyl compounds

Te-O bonds, 453 Te-P bonds, 454 Te-S bonds, 453 Te-Sb bonds, 456 Te-Se bonds, 453 Te-Te bonds, 454 Tellurium cations, 938-942 anions, 1349 cations, 1346-1349 Th-contaming species neutrals, 643-650 Th clusters, 650-651 Thiazyl compounds NSR N-S bonds, 420 -421 Thio-acid RC(0)SH S-C bonds, 438 S-H bonds, 438 Thio-aldehydes RC(S)H C-H bonds, 125 Thio-amides RC(S)NR2 ... 

The dieation (19) was found to exist in a chair conformation by x-ray analysis <91AX(C)2583> and the eonformation of the l,2,5,6-tetrathia-3,4-diazoeane (20) was shown to be a crown in the solid state, also by x-ray crystallography <77Mi926-oi>. 7- -Butyl-3-chloro-l,3,5-trithia-2,4,6,8-tetrazocine (21) was found by x-ray analysis to have the shortest transannular S—S contact (2.378 A) of any thiazyl compound <85AX(C)1686>. 

This d —p,j-bonding is not confined to simple molecules and d orbitals can also take part in delocalized r-bonding in compounds such as the cyclic phosphazenes (/) and the thiazyl compounds (II), Fig. 1. We shall review some of the thermochemical data which... 

Polymer and chain formation is another property of chalcogen-nitrogen compounds that distinguishes them from their oxygen analogues. In addition to the unique, superconducting poly(sulfur nitride) (SN) (1.24) (Section 14.2), a variety of poly(thiazyl) chains such as RS5N4R (1.25) (Section 14.3) have been characterized. Interest in these chains stems from their possible use as models for the behaviour of (SN) and as components in molecular materials, e.g., as molecular wires. 

The thiazyl cation is used for the preparation of other important S-N compounds (Scheme 5.3). For example, the insertion reactions with S4N4... 

Thiazyl fluoride is a moisture-sensitive, thermally unstable gas. It is conveniently generated by decomposition of compounds which already... 

The simplest chain compounds of the type RS NyR are the sulfur diimides RNSNR (Section 10.4) The other known thiazyl chains are summarized in Table 14.1. They can be conveniently classified as sulfur-rich, nitrogen-rich or even-chain species. 

A 2 g quantity of the product of interaction of hexacarbonylmolybdenum and thiazyl chloride, possibly constituted as shown, reacted explosively with water. See other amiaeogen compounds, n-s compounds... 

Thiazyl chloride, treated with aqueous ammonia and then silver nitrate, gives a compound AgN5S3(of unknown structure) which is shock-sensitive and explodes violently. 

Fig. 25. Schematic drawing of terphenyl-substituted thiazyl radicals and thioaminyls.121122 2. Phosphorus Compounds...

Sulphur and NItrogen —Nitrogen Sulphides, Sulphammonium, Hoxasulpli-amido, Cliloro- and Bromo-sulphides, Thiazyl Salta—Amides of the Sulphur Oxy-acids—Sulphonic Acids—Sulphur Compounds of Hydroxylaimno and Hydrazine. 

Cyclohexadiene and singlet oxygen form (103). Most of the important synthetic approaches for 1,2-thiazines use a fragment in which the S-N bond already exists. Syntheses via [4 + 2] cycloadditions constitute a major part of the synthetic repertoire for this class of compounds (CHEC-II(6)370). Thus, pentadiene with TsNSO gives (104) and perfluoro-l,2-thiazine (105) is prepared by the cycloaddition of thiazyl fluoride (FSN) and perfluoro-1,3-butadiene CF2 = CFCF = CF2 (79CC35). 

The thiazyl cation is used for the preparation of other S-N compounds (see Scheme 2). For example, the insertion reactions with S4N4 and SCI2 produce the S5N5+ (5) and C1SNSC1+ (21) cations respectively. Insertion of thiazyl cations into the metal-halogen bond of Re(CO)5X (X = Cl, Br) provides a route to thiazyl hahde complexes. 

One of the most remarkable molecules is thiazyl trifluoride, NSF (Fig. 18.7). This compound is very stable. It does not react with ammonia at room lemperaiure. with hydrogen chloride even when hented. or with metallic sodium at temperatures below 400 C. The S—N bond. 141.6 pm, is the shortest known between these two elements. The F.SF bond nngle.s of 94° are compatible with approximate j/ bonding and the presence of an rp hybrid cr bond. ind iwo p d n bonds between ihe sulfur and the niirogen. The contraccicr of ihc J orbiuils by the inductive effect of the fluorine atoms presumably permits effective overLip and -jr-bond formation. The alternative explanation would require a double dative bond from the sulfur atom, extremely unlikely in view of the positive character of ihe sulfur atom... 

Sulphur-Nitrogen Compounds.—Linear Compounds. Results from ab initio Hartree-Fock calculations on the ground states of NSF and SSO have been reported.87 The photoelectron spectra of the bent, triatomic molecules NSF, SSO, 03, S02, and NSC1 were compared and experimental details of the photoelectron spectrum of SSO presented. Pyrolysis of the tetrathiatriazyl halide S4N3X at low pressures gives the corresponding thiazyl halide XSN where X = C1 or Br but not where X = I 88... 

A study " " of reactions of cyclo-thiazyl halides with Lewis acids has shown that (SNCO3 and (SNF)j react with SbCls or SbFj, AsFj, and BF3, to give the ionic compounds[S3N,Cl2] [SbCl6] and[S3N3F2] [MF6] (BF4), respectively. On heating, the (NS)3 ring is cleaved, e.g. 

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