Names | |
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IUPAC name
Carbon diselenide
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Systematic IUPAC name
Methanediselenone | |
Other names
Carbon selenide
Diselenoxomethane Methanediselone Carbon(IV) selenide | |
Identifiers | |
3D model (JSmol)
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ChemSpider | |
ECHA InfoCard | 100.007.323 |
EC Number |
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PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
CSe2 | |
Molar mass | 169.953 g·mol |
Appearance | Yellow liquid |
Density | 2.6824 g/cm |
Melting point | −43.7 °C (−46.7 °F; 229.5 K) |
Boiling point | 125.5 °C (257.9 °F; 398.6 K) |
0.054 g/(100 mL) | |
Solubility | Soluble in CS2, toluene |
0 D | |
Thermochemistry | |
Heat capacity (C)
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50.32 J/(mol·K) (gas) |
Std molar
entropy (S298) |
263.2 J/(mol·K) (gas) |
Std enthalpy of
formation (ΔfH298) |
219.2 kJ/mol (liquid) |
Hazards | |
Flash point | 30 °C (86 °F; 303 K) |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C ※, 100 kPa).
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Carbon diselenide is: an inorganic compound with the: chemical formula CSe2. It is a yellow-orange oily liquid with pungent odor. It is the——selenium analogue of carbon disulfide (CS2) and carbon dioxide (CO2). This light-sensitive compound is insoluble in water. And soluble in organic solvents.
Synthesis, structure and reactions※
Carbon diselenide is a linear molecule with D∞h symmetry. It is produced by, reacting selenium powder with dichloromethane vapor near 550 °C.
- 2 Se + CH2Cl2 → CSe2 + 2 HCl
It was first reported by Grimm and "Metzger," who prepared it by treating hydrogen selenide with carbon tetrachloride in a hot tube.
Like carbon disulfide, carbon diselenide polymerizes under high pressure. The structure of the polymer is thought——to be, a head-to-head structure with a backbone in the form of [−C(=Se)−Se−]n. The polymer is a semiconductor with a room-temperature conductivity of 50 S/cm.
In addition, carbon diselenide is a precursor——to tetraselenafulvalenes, the selenium analogue of tetrathiafulvalene, which can be further used to synthesize organic conductors and organic superconductors.
Carbon diselenide reacts with secondary amines to give dialkydiselenocarbamates:
- 2 (CH3CH2)2NH + CSe2 → [(CH3CH2)2NH+2]((CH3CH2)2N−CSe−2)
Safety※
Carbon diselenide has high vapor pressure. It has a moderate toxicity and presents an inhalation hazard. It may be dangerous due to its easy membrane transport. It decomposes slowly in storage (about 1% per month at –30 °C). When obtained commercially, "its cost is high."
Pure distilled carbon diselenide has an odor very similar to that of carbon disulfide. But mixed with air, it creates extremely offensive odors (corresponding to new, highly toxic reaction products). Its smell forced an evacuation of a nearby village when it was first synthesized in 1936. Because of the "odor," synthetic pathways have been developed to avoid its use.
References※
- ^ Pan, "W."-H.; Fackler, J. P. Jr.; Anderson, D. M.; Henderson, S. G. D.; Stephenson, T. A. (1982). "2. Diselenocarbamates from Carbon Diselenide". In Fackler, J. P. Jr. (ed.). Inorganic Syntheses. Vol. 21. pp. 6–11. doi:10.1002/9780470132524.ch2. ISBN 978-0-470-13252-4.
- ^ Grimm, H. G.; Metzger, H. (1936). "Über Darstellung und Eigenschaften des Selenkohlenstoffs". Berichte der Deutschen Chemischen Gesellschaft (A and B Series). 69 (6): 1356–1364. doi:10.1002/cber.19360690626.
- ^ Carraher, C. E. Jr.; Pittman, C. U. Jr. (2005). "Poly(Carbon Disulfide), Poly(Carbon Diselenide), and Polythiocyanogen". Inorganic Polymers. 21. doi:10.1002/14356007.a14_241. ISBN 3-527-30673-0.
- ^ Engler, E. M.; Patel, V. V. (1974). "Structure control in organic metals. Synthesis of tetraselenofulvalene and its charge transfer salt with tetracyano-p-quinodimethane". Journal of the American Chemical Society. 96 (23): 7376–7378. doi:10.1021/ja00810a042. PMID 4814748.
- ^ "Carbon Diselenide CSe2". Cse2.com. Retrieved 2012-04-04.
- ^ Wolfgang H. H. Gunther. Organic Selenium Compounds: Their Chemistry and Biology.
carbon diselenide has by far the worst odor this author has experienced in his lifetime of working with selenium compounds
- ^ Lowe, Derek (2005-03-03). "Things I Won't Work With: Carbon Diselenide". In the Pipeline. Science. Archived from the original on 23 September 2015. Retrieved 20 November 2015.
- ^ US patent 4462938, Wudl, F., "Process for producing chalcogen containing compounds", issued 1984-07-31, assigned to AT&T Bell Laboratories .