Tetrahydrothiophene

Tetrahydrothiophene is an organosulfur compound with the formula (CH₂)₄S. The molecule consists of a five-membered saturated ring with four methylene groups and a sulfur atom. It is the saturated analog of thiophene and is therefore the sulfur analog of THF. It is a volatile, colorless liquid with an intensely unpleasant odor. It is also known as thiophane, thiolane, or THT.

Tetrahydrothiophene

Names
Preferred IUPAC name Thiolane
Other names Tetrahydrothiophene, thiophane, tetramethylene sulfide
Identifiers
CAS Number	110-01-0 Y
3D model (JSmol)	Interactive image
Abbreviations	THT
Beilstein Reference	102392
ChEBI	CHEBI:48458 Y
ChEMBL	ChEMBL1379 Y
ChemSpider	1095 Y
ECHA InfoCard	100.003.391
EC Number	203-728-9
PubChem CID	1127
RTECS number	XN0370000
UNII	744EHT13FM Y
UN number	2412
CompTox Dashboard (EPA)	DTXSID3047760
InChI InChI=1S/C4H8S/c1-2-4-5-3-1/h1-4H2 Y Key: RAOIDOHSFRTOEL-UHFFFAOYSA-N Y InChI=1/C4H8S/c1-2-4-5-3-1/h1-4H2 Key: RAOIDOHSFRTOEL-UHFFFAOYAY
SMILES S1CCCC1
Properties
Chemical formula	C4H8S
Molar mass	88.17 g·mol−1
Appearance	colorless liquid
Density	0.997 g/mL[1]
Melting point	−96 °C (−141 °F; 177 K)
Boiling point	119 °C (246 °F; 392 K)
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Stench, flammable, irritant
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H225, H302, H312, H315, H319, H332, H412
Precautionary statements	P210, P233, P240, P241, P242, P243, P261, P264, P270, P271, P273, P280, P301+P312, P302+P352, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P312, P321, P322, P330, P332+P313, P337+P313, P362, P363, P370+P378, P403+P235, P501
Flash point	12 °C (54 °F; 285 K)
Autoignition temperature	200 °C (392 °F; 473 K)
Safety data sheet (SDS)	Oakwood
Related compounds
Related compounds	Tetrahydrofuran, Thiophene, Selenolane, Thiazolidine, Dithiolane, Thiane
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Synthesis and reactions

Tetrahydrothiophene is prepared by the reaction of tetrahydrofuran with hydrogen sulfide. This vapor-phase reaction is catalyzed by alumina and other heterogenous acid catalysts.^[2][3]

This compound is a ligand in coordination chemistry, an example being the complex chloro(tetrahydrothiophene)gold(I).^[4]

Oxidation of THT gives the sulfone sulfolane, which is of interest as a polar, odorless solvent:

C₄H₈S + 2 O → C₄H₈SO₂

Sulfolane is, however, more conventionally prepared from butadiene.

Natural occurrence

Both unsubstituted and substituted tetrahydrothiophenes are reported to occur in nature. For example, tetrahydrothiophene occurs as a volatile from Eruca sativa Mill. (salad rocket)^[5] while monocyclic substituted tetrahydrothiophenes have been isolated from Allium fistulosum 'Kujou',^[6] Allium sativum (garlic),^[7] Allium cepa (onion),^[8] Allium schoenoprasum (chives),^[9] and Salacia prinoides.^[10] Albomycins are a group of tetrahydrothiophene-ring containing antibiotics from streptomyces while biotin and neothiobinupharidine (and other nuphar alkaloids ^[11]), are examples of bicyclic and polycyclic tetrahydrothiophene-ring containing natural products, respectively.

Applications

Because of its smell, tetrahydrothiophene has been used as an odorant in LPG,^[3] albeit no longer in North America. It is also used as an odorant for natural gas, usually in mixtures containing tert-butylthiol.

Tetrahydrothiophene is a Lewis base classified as a soft base and its donor properties are discussed in the ECW model.

See also

• Tetrahydrofuran
• Thiophene