Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Dimethyl carbonate: Difference between pages

{{distinguish|dimethyl carbate}}

| Watchedfields = changed

| verifiedrevid = 476999619

| Name = Dimethyl carbonate

| ImageFile = Dimethyl carbonate Structural Formulae.svg

| ImageSize = 180px

| ImageName = Dimethyl carbonate

| ImageFile1 = Dimethyl-carbonate-cis-cis-HF-3D-balls.png

| ImageSize1 = 150px

| ImageName1 = Ball-and-stick model of dimethyl carbonate

| PIN = Dimethyl carbonate

| OtherNames = DMC<br />Methyl carbonate, di-

|Section1={{Chembox Identifiers

| ChEBI_Ref = {{ebicite|correct|EBI}}

| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = KE9J097SPN

|Section2={{Chembox Properties

| C=3|H=6|O=3

| Appearance = colorless liquid

| Density = 1.069-1.073 g/mL

| Solubility = 13.9 g/100 mL

| MeltingPtC = 2 to 4

| BoilingPtC = 90

| Viscosity =

|Section7={{Chembox Hazards

| ExternalSDS =

| MainHazards = Flammable

| FlashPtC = 17

'''Dimethyl carbonate''' ('''DMC''') is an [[organic compound]] with the [[chemical formula|formula]] OC(OCH₃)₂. It is a colourless, flammable liquid. It is classified as a [[carbonate ester]]. This compound has found use as a [[methylating agent]] and as a co-solvent in [[lithium-ion batteries]].<ref>{{cite journal |last1=Köntje |first1=M. |last2=Memm |first2=M. |last3=Axmann |first3=P. |last4=Wohlfahrt-Mehrens |first4=M. |title=Substituted transition metal phospho olivines LiMM′PO4 (M = Mn, M′ = Fe, Co, Mg): Optimisation routes for LiMnPO4 |journal=Progress in Solid State Chemistry |date=December 2014 |volume=42 |issue=4 |pages=106–117 |doi=10.1016/j.progsolidstchem.2014.04.005 }}</ref> Notably, dimethyl carbonate is a weak [[methylating agent]], and is not considered as a [[carcinogen]].<ref>https://www.fsc.go.jp/fsciis/attachedFile/download?retrievalId=kya20180111146&fileId=202{{full|date=October 2023}}</ref> Instead, dimethyl carbonate is often considered to be a [[green chemistry|green reagent]],<ref>{{Kirk-Othmer | doi = 10.1002/0471238961.0301180204011312.a01.pub2 | title = Chloroformates and Carbonates | year = 2001 | last1 = Kreutzberger | first1 = Charles B. | mode = cs1}}</ref><ref>{{cite journal |last1=Seo |first1=Dongseok |title=Toxicity assessment of dimethyl carbonate following 28 days repeated inhalation exposure |journal=Environmental Analysis, Health and Toxicology |date=16 June 2021 |volume=36 |issue=2 |pages=e2021012-0 |doi=10.5620/eaht.2021012 |pmid=34130377 |pmc=8421751 }}</ref>

and it is exempt from the restrictions placed on most [[volatile organic compound]]s (VOCs) in the United States.<ref>{{Cite web|url=https://www.paint.org/voc-exempt/|title=Update: U.S. EPA Exempt Volatile Organic Compounds|date=2018-01-30|website=American Coatings Association|language=en-US|access-date=2019-03-20|archive-date=2021-02-08|archive-url=https://web.archive.org/web/20210208171107/https://www.paint.org/voc-exempt/|url-status=dead}}</ref>

==Production==

World production in 1997 was estimated at 1000 barrels a day.<ref name = pachecho/> Production of dimethyl carbonate worldwide is limited to Asia, the Middle East, and Europe.

Dimethyl carbonate is traditionally prepared by the reaction of [[phosgene]] and [[methanol]]. [[Methyl chloroformate]] is produced as an intermediate:

: COCl₂ + CH₃OH → CH₃OCOCl + HCl

: CH₃OCOCl + CH₃OH → CH₃OCO₂CH₃ + HCl

This synthesis route has been largely replaced by [[oxidative carbonylation]]. In this process, [[carbon monoxide]] and an oxidizer provide the equivalent of CO²⁺:<ref name=Tundo/><ref name = ullmann>{{Ullmann | doi = 10.1002/14356007.a05_197 | title = Carbonic Esters | author = Hans-Josef Buysch }}</ref>

:: CO + 1/2 O₂ + 2 CH₃OH → (CH₃O)₂CO + H₂O

It can also be produced industrially by a [[transesterification]] of [[ethylene carbonate]] or [[propylene carbonate]] and [[methanol]], which also affords respectively ethylene glycol or [[propylene glycol]]. This route is complicated by the methanol-DMC [[azeotrope]], which requires [[azeotropic distillation]] or other techniques.<ref>{{Cite journal |last=Patraşcu |first=Iulian |last2=Bîldea |first2=Costin S. |last3=Kiss |first3=Anton A. |date=2022-02-01 |title=Novel eco-efficient reactive distillation process for dimethyl carbonate production by indirect alcoholysis of urea |url=https://doi.org/10.1007/s11705-021-2047-9 |journal=Frontiers of Chemical Science and Engineering |language=en |volume=16 |issue=2 |pages=316–331 |doi=10.1007/s11705-021-2047-9 |issn=2095-0187}}</ref>

==Reactions and potential applications==

===Methylating agent===

Dimethyl carbonate methylates [[aniline]]s, [[carboxylic acid]]s, and [[phenols]], albeit usually slowly.<ref>{{cite journal |last1=Lee |first1=Youngmin |last2=Shimizu |first2=Isao |title=Convenient O-Methylation of Phenols with Dimethyl Carbonate |journal=Synlett |date=1998 |volume=1998 |issue=10 |pages=1063–1064 |doi=10.1055/s-1998-1893 |s2cid=196807122 }}</ref><ref name=Shieh2002>{{cite journal | last = Shieh | first = Wen-Chung |author2=Dell, Stephen |author3=Repič, Oljan | title = Nucleophilic Catalysis with 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) for the Esterification of Carboxylic Acids with Dimethyl Carbonate | journal = [[J. Org. Chem.]] | volume = 67 | issue = 7 | pages = 2188–2191 | year = 2002 | doi =10.1021/jo011036s| pmid = 11925227 }}</ref><ref>{{cite journal | doi = 10.1021/ol016949n | pmid = 11784197 | title = 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU) and Microwave-Accelerated Green Chemistry in Methylation of Phenols, Indoles, and Benzimidazoles with Dimethyl Carbonate | year = 2001 | last1 = Shieh | first1 = Wen-Chung | last2 = Dell | first2 = Steven | last3 = Repič | first3 = Oljan | journal = Organic Letters | volume = 3 | issue = 26 | pages = 4279–81}}</ref> Sometimes these reactions require the use of an [[autoclave]].

:[[Image:DMC Methylation.png|350px|Methylation of phenylacetic acid by dimethyl carbonate promoted by DBU]]

Dimethyl carbonate's main benefit over other methylating reagents such as [[iodomethane]] and [[dimethyl sulfate]] is its low toxicity. Additionally, it is biodegradable.<ref name=Tundo>{{cite journal | title = The Chemistry of Dimethyl Carbonate | author = Pietro Tundo | author2 = Maurizio Selva | name-list-style = amp | journal = [[Acc. Chem. Res.]] | volume = 35 | issue = 9 | year = 2002 | pages = 706–16 | doi = 10.1021/ar010076f| pmid = 12234200 }}</ref> Unfortunately, it is a relatively weak [[methylating agent]] compared to these traditional reagents.

===Solvent===

In the US, dimethyl carbonate was exempted under the definition of [[volatile organic compound]]s (VOCs) by the [[U.S. EPA]] in 2009.<ref>http://www.epa.gov/ttn/oarpg/t1/fact_sheets/voc_exemp01011309.pdf {{Webarchive|url=https://web.archive.org/web/20210208171047/https://www.epa.gov/technical-air-pollution-resources |date=2021-02-08 }}{{full|date=October 2023}} Information about the EPA's action on exempting dimethyl carbonate as a VOC and petitioner's background information, public comments and other references are available electronically at http://www.regulations.gov, EPA's electronic public docket and comment system. The docket number for this action is Docket ID No. EPA-HQ-OAR-2006-0948. See http://www.epa.gov/ttn/oarpg/t1pfpr.html {{Webarchive|url=https://web.archive.org/web/20120107130412/http://www.epa.gov/ttn/oarpg/t1pfpr.html |date=2012-01-07 }}{{full|date=October 2023}} and scroll down to Jan 13, 2009 pdf for the rule.</ref> Due to its classification as VOC exempt, dimethyl carbonate has grown in popularity and applications as a replacement for [[methyl ethyl ketone]] (MEK) and [[parachlorobenzotrifluoride]], as well as [[tert-Butyl acetate|''tert''-butyl acetate]] until it too was exempted.<ref>{{Cite web|last=|first=|date=2018-01-30|title=Update: U.S. EPA Exempt Volatile Organic Compounds|url=https://www.paint.org/voc-exempt/|url-status=live|archive-url=https://web.archive.org/web/20190320200925/https://www.paint.org/voc-exempt/ |archive-date=2019-03-20 |access-date=June 23, 2020|website=American Coatings Association}}</ref> Dimethyl carbonate has an ester- or alcohol-like odor, which is more favorable to users than most hydrocarbon solvents it replaces. Dimethyl carbonate has an evaporation rate of 3.22 (butyl acetate = 1.0), which slightly slower than MEK (3.8) and [[ethyl acetate]] (4.1), and faster than [[toluene]] (2.0) and [[isopropanol]] (1.7). Dimethyl carbonate has solubility profile similar to common [[glycol ether]]s, meaning dimethyl carbonate can dissolve most common coating resins except perhaps rubber based resins. Hildebrand solubility parameter is 20.3 MPa and Hansen solubility parameters are: dispersion = 15.5, polar = 3.9, H bonding = 9.7.<ref>{{cite book|last1=Kanegsberg|first1=Barbara|last2=Kanegsberg|first2=Edward|title=Handbook for Critical Cleaning: Cleaning Agents and Systems, Second Edition|url=https://archive.org/details/handbookforcriti00kane_413|url-access=limited|publisher=CRC Press|isbn=9781439828281|page=[https://archive.org/details/handbookforcriti00kane_413/page/n45 16]|edition=Second|date=2011-04-04}}</ref> Dimethyl carbonate is partially soluble in water up to 13%, however it is hydrolyzed in water-based systems over time to methanol and CO₂ unless properly buffered.

Dimethyl carbonate can freeze at same temperatures as water, it can be thawed out with no loss of properties to itself or coatings based on dimethyl carbonate.

===Intermediate in polycarbonate synthesis===

A large captive use of dimethyl carbonate is for the production of [[diphenyl carbonate]] through [[transesterification]] with [[phenol]]. Diphenyl carbonate is a widely used raw material for the synthesis of [[bisphenol A|bisphenol-A]]-polycarbonate in a melt polycondensation process,<ref>{{cite book|last = Fukuoka|first = Shinsuke|publisher = [[Nova Science Publishers]]|title = Non-Phosgene Polycarbonate from CO₂ - Industrialization of Green Chemical Process|year = 2012|isbn = 9781614708773}}</ref> the resulting product being recyclable by reversing the process and transesterifying the polycarbonate with phenol to yield diphenyl carbonate and bisphenol A.<ref>{{Ullmann|doi = 10.1002/14356007.a05_197|title = Carbonic Esters|first = Hans-Josef|last = Buysch|year = 2000}}</ref>

===Alternative fuel additive===

There is also interest in using this compound as a [[fuel oxygenate additive]].<ref name = pachecho>{{cite journal | doi = 10.1021/ef9600974 | journal = [[Energy & Fuels]] | title = Review of Dimethyl Carbonate (DMC) Manufacture and Its Characteristics as a Fuel Additive | year = 1997 | last1 = Pacheco | first1 = Michael A. | last2 = Marshall | first2 = Christopher L. | volume = 11 | pages = 2–29}}</ref>

===In lithium-ion and lithium-metal batteries===

Similar to [[ethylene carbonate]], dimethyl carbonate forms an electronically-insulating Li⁺-conducting film at negative [[electrode potentials]]. However, the film in dry DMC solutions is not as effective in passivating the negative electrode as the film in wet solutions.<ref>{{cite journal |last1=Aurbach |first1=Doron |last2=Ein‐Eli |first2=Yair |title=The Study of Li‐Graphite Intercalation Processes in Several Electrolyte Systems Using In Situ X‐Ray Diffraction |journal=Journal of the Electrochemical Society |date=June 1995 |volume=142 |issue=6 |pages=1746–1752 |doi=10.1149/1.2044188 |bibcode=1995JElS..142.1746A }}</ref> For this reason dimethyl carbonate is rarely used in lithium batteries without a co-solvent.<ref>{{cite journal |last1=Aurbach |first1=D. |last2=Markovsky |first2=B. |last3=Shechter |first3=A. |last4=Ein‐Eli |first4=Y. |last5=Cohen |first5=H. |title=A Comparative Study of Synthetic Graphite and Li Electrodes in Electrolyte Solutions Based on Ethylene Carbonate‐Dimethyl Carbonate Mixtures |journal=Journal of the Electrochemical Society |date=December 1996 |volume=143 |issue=12 |pages=3809–3820 |doi=10.1149/1.1837300 |bibcode=1996JElS..143.3809A }}</ref>

==Safety==

DMC is a flammable liquid with a [[flash point]] of 17&nbsp;°C (63&nbsp;°F), which limits its use in consumer and indoor applications. DMC is still safer than [[acetone]], [[methyl acetate]] and methyl ethyl ketone from a flammability point of view. The [[University Transportation Centers Program|National Center for Sustainable Transportation]] recommends limiting exposure by inhalation to less than 100 ppm over an 8-hour work day, which is similar to that of a number of common industrial solvents ([[toluene]], methyl ethyl ketone).<ref>{{cite book |last1=Durbin |first1=Thomas D. |last2=Karavalakis |first2=Georgios |last3=Johnson |first3=Kent C. |last4=Cocker |first4=David |last5=Yang |first5=Jiacheng |last6=Jiang |first6=Yu |last7=Kumar |first7=Sachin |title=Evaluating the viability of dimethyl carbonate as an alternative fuel for the transportation sector |date=June 2017 |url=https://rosap.ntl.bts.gov/view/dot/32485 }}</ref> Workers should wear protective organic vapor respirators when using DMC indoors or in other conditions where concentrations exceed the REL. DMC is metabolized by the body to [[methanol]] and carbon dioxide, so accidental ingestion should be treated in the same manner as [[methanol poisoning]].{{fact|date=October 2023}}

==See also==

*[[Dimethyl dicarbonate]]

==References==

<references/>

[[Category:Methylating agents]]

[[Category:Carbonate esters]]

[[Category:Methyl esters]]