:Carbon diselenide
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|Verifiedfields = changed
|Watchedfields = changed
|verifiedrevid = 451704182
|ImageFile1 = Carbon_diselenide.png
|ImageSize1 = 150px
|ImageFile2 = Carbon-diselenide-3D-balls.png
|ImageSize2 = 150px
|ImageFile3 = Carbon-diselenide-3D-vdW.png
|ImageName = Carbon diselenide
|OtherNames = Carbon selenide
Diselenoxomethane
Methanediselone
Carbon(IV) selenide
|IUPACName = Carbon diselenide
|SystematicName = Methanediselenone
|Section1 = {{Chembox Identifiers
|CASNo_Ref = {{cascite|correct|??}}
|CASNo = 506-80-9
|UNII_Ref = {{fdacite|correct|FDA}}
|UNII = WD123H448C
|PubChem = 68174
|ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
|ChemSpiderID = 61481
|EC_number = 208-054-9
|SMILES = [Se]=C=[Se]
|InChI = 1/CSe2/c2-1-3
|InChIKey = JNZSJDBNBJWXMZ-UHFFFAOYAM
|StdInChI_Ref = {{stdinchicite|correct|chemspider}}
|StdInChI = 1S/CSe2/c2-1-3
|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
|StdInChIKey = JNZSJDBNBJWXMZ-UHFFFAOYSA-N
}}
|Section2 = {{Chembox Properties
|Formula = {{chem2|CSe2}}
|C=1|Se=2
|Appearance = Yellow liquid
|Density = 2.6824 g/cm3
|Solubility = 0.054 g/(100 mL)
|SolubleOther = Soluble in carbon disulfide, toluene
|MeltingPtC = −43.7
|BoilingPtC = 125.5
|Dipole = 0 D
}}
|Section3 = {{Chembox Thermochemistry
|DeltaHf = 219.2 kJ/mol (liquid)
|Entropy = 263.2 J/(mol·K) (gas)
|HeatCapacity = 50.32 J/(mol·K) (gas)
}}
|Section4 = {{Chembox Hazards
|FlashPtC = 30
}}
}}
Carbon diselenide is an inorganic compound with the chemical formula {{chem2|CSe2}}. It is a yellow-orange oily liquid with pungent odor. It is the selenium analogue of carbon disulfide ({{chem2|CS2}}) and carbon dioxide ({{chem2|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.{{cite book |editor1-link=John P. Fackler Jr. | editor = Fackler, J. P. Jr. |author1=Pan, W.-H. |author2=Fackler, J. P. Jr. |author3=Anderson, D. M. |author4=Henderson, S. G. D. |author5=Stephenson, T. A. | chapter = 2. Diselenocarbamates from Carbon Diselenide | title = Inorganic Syntheses | volume = 21 | pages = 6–11 | year = 1982 | doi = 10.1002/9780470132524.ch2 | isbn = 978-0-470-13252-4}}
:{{chem2|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.{{cite journal | title = Über Darstellung und Eigenschaften des Selenkohlenstoffs | journal = Berichte der Deutschen Chemischen Gesellschaft (A and B Series) | volume = 69 |issue = 6 | year = 1936 | pages = 1356–1364 |author1=Grimm, H. G. |author2=Metzger, H. | doi = 10.1002/cber.19360690626}}
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 {{chem2|[\sC(\dSe)\sSe\s]_{n}|}}.{{cite journal |author1=Carraher, C. E. Jr. |author2=Pittman, C. U. Jr. | title = Poly(Carbon Disulfide), Poly(Carbon Diselenide), and Polythiocyanogen | journal = Inorganic Polymers | year = 2005 | volume = 21 | doi = 10.1002/14356007.a14_241 | isbn = 3-527-30673-0}}
The polymer is a semiconductor with a room-temperature conductivity of 50 S/cm.
In addition, carbon diselenide is a precursor to tetraselenafulvalenes,{{cite journal |author1=Engler, E. M. |author2=Patel, V. V. | title = Structure control in organic metals. Synthesis of tetraselenofulvalene and its charge transfer salt with tetracyano-p-quinodimethane | journal = Journal of the American Chemical Society | year = 1974 | volume = 96 | issue = 23 | pages = 7376–7378 | doi = 10.1021/ja00810a042 |pmid=4814748}} 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 {{chem name|dialkydiselenocarbamates}}:
:{{chem2|2 (CH3CH2)2NH + CSe2 → [(CH3CH2)2NH2+]((CH3CH2)2N\sCSe2−)}}
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.{{cite web | url = http://www.cse2.com/ | title = Carbon Diselenide CSe2 | publisher = Cse2.com | accessdate = 2012-04-04}}
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).{{cite book | quote = carbon diselenide has by far the worst odor this author has experienced in his lifetime of working with selenium compounds | author = Wolfgang H. H. Gunther | title = Organic Selenium Compounds: Their Chemistry and Biology}}{{cite web | last1 = Lowe | first1 = Derek | archiveurl = https://web.archive.org/web/20150923230748/http://blogs.sciencemag.org/pipeline/archives/2005/03/03/things_i_wont_work_with_carbon_diselenide/ | archivedate = 23 September 2015 | url = http://blogs.sciencemag.org/pipeline/archives/2005/03/03/things_i_wont_work_with_carbon_diselenide/ | title = Things I Won't Work With: Carbon Diselenide | work = In the Pipeline | publisher = Science | access-date = 20 November 2015 | authorlink = Derek Lowe (chemist) | date = 2005-03-03}} 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.{{cite patent | country = US | number = 4462938 | status = patent | inventor = Wudl, F. | assign1 = AT&T Bell Laboratories | gdate = 1984-07-31 | title = Process for producing chalcogen containing compounds}}.
References
{{reflist}}
{{Carbon compounds}}
{{Selenides}}
Category:Inorganic carbon compounds