Carbon subsulfide

Carbon subsulfide

Names
Preferred IUPAC name Propa-1,2-diene-1,3-dithione
Other names Carbon Subsulfide, Tricarbon Disulfide
Identifiers
CAS Number	627-34-9 Y
3D model (JSmol)	Interactive image
ChemSpider	9237470 N
PubChem CID	11062317
CompTox Dashboard (EPA)	DTXSID20453695
InChI InChI=1S/C3S2/c4-2-1-3-5 N Key: RMCQREAPGZPWGK-UHFFFAOYSA-N N InChI=1/C3S2/c4-2-1-3-5 Key: RMCQREAPGZPWGK-UHFFFAOYAC
SMILES S=C=C=C=S
Properties
Chemical formula	C3S2
Molar mass	100.15 g·mol−1
Appearance	red liquid
Density	1.27 g cm−3
Melting point	−1 °C (30 °F; 272 K)
Boiling point	90 °C (194 °F; 363 K)
Solubility in water	insoluble
Related compounds
Related compounds	Carbon suboxide Carbon disulfide Ethenedithione
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Carbon subsulfide is an organic, sulfur-containing chemical compound with the formula C₃S₂ and structure S=C=C=C=S. This deep red liquid is immiscible with water but soluble in organic solvents. It readily polymerizes at room temperature to form a hard black solid.

C₃S₂ was discovered by Béla Lengyel,^[1] who assigned it an unsymmetrical structure. Later, infrared and Raman spectroscopy showed that the structure is symmetrical with a D_∞h point group symmetry,^[2] i.e. S=C=C=C=S. This compound is analogous to carbon suboxide whose structure is O=C=C=C=O.

Lengyel first synthesized this compound by passing carbon disulfide (CS₂) vapor through an electric arc with carbon electrodes. This treatment produced a black solution that after filtration and evaporation gave a cherry-red liquid. He determined the molecular mass by cryoscopy. Later preparations of C₃S₂ include thermolysis of a stream of CS₂ in a quartz tube heated to 900 to 1100 °C as well as flash vacuum pyrolysis (FVP) of 1,2-dithiole-3-thiones.^[3]

Among its few known reactions, C₃S₂ reacts with bromine to form the cyclic disulfide.^[4]

C₃S₂ polymerizes under applied pressure to give a black semi-conducting solid. A similar pressure-induced polymerization of CS₂ also gives a black semiconducting polymer.

In addition, reactions of C₃S₂ can yield highly condensed sulfur-containing compounds, e.g. the reaction of C₃S₂ with 2-aminopyridine.

Using microwave spectroscopy, small C_nS₂ clusters have been detected in interstellar medium.^[5] The rotational transitions of these molecular carbon sulfides matched with the corresponding molecules.