Tetramethylammonium chloride
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 389387218
| ImageFile1 = Tetramethylammonium-chloride-ion-pair-2D.png
| ImageFile2 = Tetramethylammonium-3D-balls.png
| ImageCaption2 = Tetramethylammonium ion. Blue: nitrogen, black: carbon, white: hydrogen
| ImageFile3 = Tetramethylammonium chloride.jpg
| PIN = N,N,N-Trimethylmethanaminium chloride
| OtherNames = Tetramethylammonium chloride
Tetramethylazanium chloride
|Section1={{Chembox Identifiers
| CASNo = 75-57-0
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = DCQ9S88703
| PubChem = 6379
| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
| ChemSpiderID = 6139
| InChI = 1/C4H12N.ClH/c1-5(2,3)4;/h1-4H3;1H/q+1;/p-1
| InChIKey = OKIZCWYLBDKLSU-REWHXWOFAY
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| StdInChI = 1S/C4H12N.ClH/c1-5(2,3)4;/h1-4H3;1H/q+1;/p-1
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| StdInChIKey = OKIZCWYLBDKLSU-UHFFFAOYSA-M
| SMILES = C[N+](C)(C)C.[Cl-]
}}
|Section2={{Chembox Properties
| Formula = C4H12NCl
| MolarMass = 109.60 g/mol
| Appearance = White crystals
| Density = 1.17 g/cm3
| MeltingPtC = 425
| MeltingPt_notes = (decomposes)
| BoilingPt =
| SolubleOther = Soluble in water and methanol. Slightly soluble in ethanol. Insoluble in ether, benzene, chloroform.
}}
|Section3={{Chembox Hazards
| ExternalSDS = [http://msds.chem.ox.ac.uk/TE/tetramethylammonium_chloride.html External MSDS]
| MainHazards =
| FlashPt =
| AutoignitionPt =
| HPhrases =
| PPhrases =
| GHS_ref =
}}
|Section8={{Chembox Related
| OtherAnions = tetramethylammonium hydroxide
| OtherCations = tetraethylammonium chloride
}}
}}
Tetramethylammonium chloride is one of the simplest quaternary ammonium salts, with four methyl groups tetrahedrally attached to the central N. The chemical formula (CH3)4N+Cl− is often abbreviated further as Me4N+Cl−. It is a hygroscopic colourless solid that is soluble in water and polar organic solvents. Tetramethylammonium chloride is a major industrial chemical, being used widely as a chemical reagent{{Cite web |url=http://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+7987 |title=Tetramethylammonium chloride - National Library of Medicine HSDB Database |access-date=2012-09-24 |archive-date=2015-12-22 |archive-url=https://web.archive.org/web/20151222014215/http://toxnet.nlm.nih.gov/cgi-bin/sis/search/a?dbs+hsdb:@term+@DOCNO+7987 |url-status=dead }} and also as a low-residue bactericide in such processes as hydrofracking.{{Cite web |url=http://fracfocus.org/chemical-use/what-chemicals-are-used |title=What Chemicals Are Used | FracFocus Chemical Disclosure Registry |access-date=2012-10-30 |archive-date=2013-08-14 |archive-url=https://web.archive.org/web/20130814180235/http://fracfocus.org/chemical-use/what-chemicals-are-used |url-status=dead }} In the laboratory, it has fewer synthetic chemical applications than quaternary ammonium salts containing longer N-alkyl substituents, which are used extensively as phase-transfer catalysts.
Preparation and laboratory uses
Tetramethylammonium chloride is efficiently produced by the reaction of trimethylamine and methyl chloride.{{Ullmann |doi=10.1002/14356007.a16_535|title=Methylamines|year=2000|last1=Van Gysel|first1=August B.|last2=Musin|first2=Willy}}
:N(CH3)3 + CH3Cl → N(CH3)4+Cl−
It is produced by the alkylation of ammonium chloride with dimethyl carbonate in the presence of an ionic liquid catalyst.{{Cite journal | last1 = Zheng | first1 = Z. | last2 = Wang | year = 2007 | first2 = Jie | last3 = Wu | first3 = Ting Hua | last4 = Zhou | first4 = Xiao Ping | title = Alkylation of Ammonium Salts Catalyzed by Imidazolium-Based Ionic Liquid Catalysts | journal = Advanced Synthesis & Catalysis | volume = 349 | issue = 7| pages = 1095–1101 | doi = 10.1002/adsc.200600451 |display-authors=etal}}
Except under extraordinary conditions,{{cite journal|last1=Nenad|first1=Maraš|last2=Polanc|first2=Slovenko|last3=Kočevar|first3=Marijan|title=Microwave-assisted methylation of phenols with tetramethylammonium chloride in the presence of K2CO3 or Cs2CO3|journal=Tetrahedron|date=2008|volume=64|issue=51|pages=11618–11624|doi=10.1016/j.tet.2008.10.024}} it is typically employed as a source of the inert counter cation Me4N+. Similarly, it serves as a lipophilic precipitating agent.{{OrgSynth
| author =W. J. Middleton and D. W. Wiley
| year =1973
| title =tetramethylammonium 1-Propene-1,1,2,3,3-pentacarbonitrile
| volume =
| pages =
| collvol =5
| collvolpages =1013
| doi =10.15227/orgsyn.041.0099}}
In low concentrations, it is used in polymerase chain reactions to increase yields and specificity. It has been shown to enhance yields 5–10 fold at 60mM by stabilizing the AT base pairs.Chevet E. et al. (1995). "Low concentrations of tetramethylammonium chloride increase yield and specificity of PCR". Nucleic Acids Research 23 (16) 3343–344.
Toxicity
LD50 = 25 mg/kg (mouse, i.p.); 40 mg/kg (mouse, s.c.); 50 mg/kg (rat, p.o.). Very toxic to aquatic organisms.{{cite web|url=https://datasheets.scbt.com/sc-251199.pdf|title=Tetramethylammonium chloride|website=Datasheets.scbt.com|access-date=14 March 2022}}
Diverse data on human exposure, environmental toxicology and environmentally-related chemistry is available through the NIH Toxnet database.
See also
References
{{Reflist}}