Methyl isocyanide
{{distinguish|Methyl isocyanate}}
{{Chembox
| Watchedfields = changed
| verifiedrevid = 455280169
| ImageFile1 = Methyl isocyanide.svg
| ImageSize1 = 180px
| ImageFile2 = Methyl-isocyanide-3D-balls.png
| ImageSize2 = 150px
| IUPACName = Isocyanomethane
| OtherNames = {{ubl|Methyl isocyanide| Isoacetonitrile| Methylisonitrile| Isomethanenitrile| Methaneisonitrile}}
|Section1={{Chembox Identifiers
| Abbreviations =
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 11156
| InChI = 1/C2H3N/c1-3-2/h1H3
| InChIKey = ZRKSVHFXTRFQFL-UHFFFAOYAI
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C2H3N/c1-3-2/h1H3
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = ZRKSVHFXTRFQFL-UHFFFAOYSA-N
| CASNo = 593-75-9
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = B5B6DXM7GG
| EC_number = 209-806-9
| PubChem = 11646
| DrugBank_Ref = {{drugbankcite|correct|drugbank}}
| DrugBank = DB04337
| SMILES = [C-]#[N+]C
| RTECS =
| MeSHName =
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 44177
| KEGG_Ref = {{keggcite|correct|kegg}}
| KEGG =
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|Section2={{Chembox Properties
| H=3 | N=1 | C=2
| Appearance = Colorless liquid
| Density = 0.69 g/mL
| MeltingPtC = −45
| MeltingPt_notes =
| BoilingPtC = 59 to 60
| BoilingPt_notes =
| Solubility = Miscible
| SolubleOther =
| Solvent =
| pKb =
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|Section7={{Chembox Hazards
| MainHazards =
| NFPA-H = 2
| NFPA-F = 3
| NFPA-R = 0
| NFPA-S =
| GHSPictograms = {{GHS07}}{{GHS08}}
| GHSSignalWord = Warning
| HPhrases = {{H-phrases|302|312|332|373}}
| PPhrases = {{P-phrases|260|261|264|270|271|280|301+312|302+352|304+312|304+340|312|314|322|330|363|501}}
| AutoignitionPt =
| ExploLimits =
| PEL =
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|Section8={{Chembox Related
| OtherAnions =
| OtherCations =
| OtherFunction =
| OtherFunction_label =
| OtherCompounds = acetic acid, acetamide, ethylamine, Acetonitrile}}
}}
Methyl isocyanide or isocyanomethane is an organic compound and a member of the isocyanide family. This colorless liquid is isomeric and isoelectronic to methyl cyanide (acetonitrile), but its reactivity is very different. In contrast to the faintly sweet, ethereal odor of acetonitrile, the smell of methyl isocyanide, like that of other simple volatile isocyanides, is distinctly penetrating and vile.{{cite book|url=https://archive.org/details/gergel_isopropyl_bromide|title=Excuse me sir, would you like to buy a kilo of isopropyl bromide?|first=Max G.|last=Gergel|author-link=Max Gergel|date=March 1977|publisher=Pierce Chemical|page=115}} Methyl isocyanide is mainly used for making 5-membered heterocyclic rings. The C-N distance in methyl isocyanide is very short, 1.158 Å as is characteristic of isocyanides.{{cite journal |last1=Kessler |first1=Myer |last2=Ring |first2=Harold |last3=Trambarulo |first3=Ralph |last4=Gordy |first4=Walter |title=Microwave Spectra and Molecular Structures of Methyl Cyanide and Methyl Isocyanide |journal=Physical Review |date=July 1950 |volume=79 |issue=1 |pages=54–56 |doi=10.1103/physrev.79.54 |bibcode=1950PhRv...79...54K }}
Preparation and uses
Methyl isocyanide was first prepared by A. Gautier by reaction of silver cyanide with methyl iodide.{{cite journal | author = Gautier, A. | title = Ueber eine neue Reihe von Verbindungen, welche mit den Cyanwasserstoffsäure-Aethern isomer sind | journal = Justus Liebigs Annalen der Chemie | year = 1868 | volume = 146 | issue = 1 | pages = 119–124 | doi = 10.1002/jlac.18681460107 | url = https://zenodo.org/record/1427279 }}{{cite journal | author = Gautier, A. | title = Des Nitriles des Acides Gras: Deuxième Partie - Des Carbylamines | journal = Annales de Chimie et de Physique | year = 1869 | volume = 17 | page = 203 | url = http://gallica.bnf.fr/ark:/12148/bpt6k34827s/f102.image.langEN }} The common method for preparing methyl isocyanides is the dehydration of N-methylformamide.{{OrgSynth | author1 = R. E. Schuster|author2= James E. Scott |author3=Joseph Casanova, Jr | title = Methyl isocyanide | year = 1966 | volume = 46 | pages = 75 | doi = 10.15227/orgsyn.046.0075 }} Many metal cyanides react with methylating agents to give complexes of methyl isocyanide.{{cite journal|doi=10.1021/cr00019a016|title=Emergence of a CNH and Cyano Complex Based Organometallic Chemistry|journal=Chemical Reviews|volume=93|issue=3|pages=1243–1280|year=1993|last1=Fehlhammer|first1=Wolf P.|last2=Fritz|first2=Marcus.}} This kind of reactivity has been invoked as being relevant to the origin of life.{{Cite journal|last1=Mariani|first1=Angelica|last2=Russell|first2=David|last3=Javelle|first3=Thomas|last4=Sutherland|first4=John|year=2018|title=A Light-Releasable Potentially Prebiotic Nucleotide Activating Agent|journal=Journal of the American Chemical Society|volume=140|issue=28|pages=8657–8661|doi=10.1021/jacs.8b05189|pmid=29965757|pmc=6152610|bibcode=2018JAChS.140.8657M }}
Methyl isocyanide is useful for the preparation of diverse heterocycles. It is often used to prepare transition metal isocyanide complexes.{{ cite encyclopedia |author1=Eckert, H. |author2=Nestl, A. |author3=Ugi, I. |title=Methyl Isocyanide | encyclopedia = Encyclopedia of Reagents for Organic Synthesis | year = 2001 | publisher = John Wiley & Sons | doi = 10.1002/047084289X.rm198 |isbn=0471936235 }}
Safety
Methyl isocyanide is very endothermic (ΔfH⦵(g) = +150.2 kJ/mol, 3.66 kJ/g) and can isomerize explosively to acetonitrile.{{cite journal |last1=Clothier |first1=P. Q. E. |last2=Glionna |first2=M. T. J. |last3=Pritchard |first3=H. O. |title=Thermal explosions of methyl isocyanide in spherical vessels |journal=The Journal of Physical Chemistry |date=July 1985 |volume=89 |issue=14 |pages=2992–2996 |doi=10.1021/j100260a008 }} A sample exploded when heated in a sealed ampoule, and during redistillation at 59 °C and 1 bar, a drop of liquid fell back into the dry boiler flask and exploded violently. The explosive decomposition of methyl isocyanide has been studied in detail.{{Cite book|title=Bretherick's Handbook of Reactive Chemical Hazards |via= ScienceDirect|url=https://www.sciencedirect.com/book/9780081009710/brethericks-handbook-of-reactive-chemical-hazards|access-date=2022-02-23|isbn=9780081009710 |language=en |last1=Urben |first1=Peter |date=22 May 2017 |publisher=Elsevier Science }}{{pn|date=June 2025}}
References
{{reflist}}
External links
- {{ cite web | url = http://webbook.nist.gov/cgi/cbook.cgi?ID=593-75-9&Units=SI | title = WebBook page for C2H3N }}
{{Molecules detected in outer space}}