Trithiazyl trichloride

Trithiazyl trichloride
Names
Other names
thionitrosyl chloride
Identifiers
3D model (JSmol)
ChemSpider
  • InChI=1S/Cl3N3S3/c1-7-4-8(2)6-9(3)5-7
    Key: QBQMTUMJJWPFDJ-UHFFFAOYSA-N
  • monomer: InChI=1S/ClNS/c1-3-2
    Key: FWVIYFTZAHMHIO-UHFFFAOYSA-N
  • trimer: ClS1=NS(Cl)=NS(Cl)=N1
  • monomer: N#SCl
Properties
(NSCl)3
Molar mass 244.55 g·mol−1
Appearance white solid
Melting point 168 °C (334 °F; 441 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Trithiazyl trichloride is the inorganic compound with the formula (NSCl)3. A white solid, it is a precursor to other sulfur nitrides,[1] but has no commercial applications.

Structure

The molecule is a 6-membered ring of alternating nitrogen and sulfur atoms, where each sulfur atom is attached to one chlorine atom by a single bond. The molecule contains alternating single and double bonds in the S3N3 core. The molecule has C3v symmetry. The S3N3 core is slightly ruffled structure with S-N distances of 160.5 pm. The S-Cl distances are 208 pm, and the chlorine atoms are mutually cis. The S centers are tetravalent and pyramidal. In contrast to the NSCl connectivity, nitrosyl chloride has the connectivity ONCl.[2][3]

Synthesis and reactions

Trithiazyl trichloride is obtained by chlorination of tetrasulfur tetranitride or thiazyl fluoride monomer:[4]

3 S4N4 + 6 Cl2 → 4 (NSCl)3
3 FSN + 3 Cl2 → (NSCl)3 + 3 ClF

At 100 °C in vacuum, thiazyl chloride trimer undergoes cracking to thiazyl chloride monomer, which is a green gas.

(−N=S(−Cl)−)3 → 3 N≡S−Cl

In N≡S−Cl, chlorine is bonded to sulfur, in contrast to nitrosyl chloride O=N–Cl, where chlorine is bonded to nitrogen. In contrast, with six fewer electrons, cyanuric chloride is a planar ring.

Alkoxide or silver salts displace the chlorides:[5]

(-NS(Cl)-)3 + 3 NaOR → (-NS(OR)-)3 + 3 NaCl
(-NS(Cl)-)3 + 3 AgX → (-NS(X)-)3 + 3 AgCl

Treating thiazyl chloride with sulfur in the presence of antimony pentachloride gives dithionitronium hexachloroantimonate:[6]

SNCl + S + SbCl5 → [NS2]SbCl6

It reacts with nitriles to dithiadiazolium chlorides:[2]

6 RCN + 4 (NSCl)3 → 6 [RCN2S2]+Cl− + 3 Cl2 + 3 N2

Sulfur trioxide successively oxidizes the compound at the sulfur atoms to (NSOCl)3,[4] which exists as stereoisomers.

References

  1. ^ Jolly, William L.; Maguire, Keith D. (1967). "Sulfur Nitrogen Chlorides". Inorganic Syntheses. Vol. IX. p. 102. doi:10.1002/9780470132401.ch27. ISBN 978-0-470-13240-1.
  2. ^ a b Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
  3. ^ Wiegers, G. A.; Vos, A. (1966). "The Crystal Structures of Two Sulfur-Nitrogen Compounds with (S-N)3 Rings. II. Trithiazylchloride, (NSCl)3, at -130 C". Acta Crystallographica. 20 (2): 192. doi:10.1107/s0365110x66000410.
  4. ^ a b Roesky, H. W. (1971). "The Sulfur–Nitrogen Bond". In Senning, Alexander (ed.). Sulfur in Organic and Inorganic Chemistry. Vol. 1. New York: Marcel Dekker. pp. 20–23. ISBN 0-8247-1615-9. LCCN 70-154612.
  5. ^ Rawson, Jeremy M.; Banister, Arthur J.; Lavender, Ian (1995). "The Chemistry of Dithiadiazolylium and Dithiadiazolyl Rings". Adv. Heterocyc. Chem. 62: 146–147. doi:10.1016/S0065-2725(08)60422-5.
  6. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.