Carbonate ester

Carbonate ester
Chemical structure of the carbonate ester group.

A carbonate ester (organic carbonate, organocarbonate) is a functional group in organic chemistry consisting of a carbonyl group flanked by two alkoxy groups. The general structure of these carbonates is R1O(C=O)OR2 and they are related to esters R1O(C=O)R and ethers R1OR2 and also to the inorganic carbonates.

Carbonate esters are used as protecting group for diols. A classic reagent is phosgene but more user friendly reagents exist such as carbonyl diimidazole. Ethylene carbonate and Propylene carbonate are used as solvents. Dimethyl carbonate is used as a methylating reagent.

In many applications a carbonate group replaces an ester group for example in Cholesteryl oleyl carbonate. Polycarbonates are an important class of polymers.

The chemistry of carbonate esters has been reviewed.[1]

Contents

Organic synthesis

Laboratory methods for the synthesis of carbonate ester in the laboratory are:

  • from the corresponding diols.
  • by double oxidation of ketones in a Baeyer-Villiger rearrangement,although this method is plausible,there is no evidence that it is effective.
  • by reaction of an epoxide with carbon dioxide catalysed by a zinc halide [2]

Use as solvents

A large number of organic carbonates are used as solvents [3]. They are classified as polar solvents and have a wide liquid temperature range. One example is polypropylene carbonate with melting point - 55°C and boiling point 240 °C. Other advantages are low ecotoxicity and good biodegradability. The industrial production of carbonates is not green because methods for production of linear carbonates rely on phosgene and those of cyclic carbonates rely on propylene oxide.

Use in batteries

Organic carbonates are used as a solvent in lithium batteries; due to their high polarity they can dissolve lithium salts. The problem of high viscosity is circumvented by using carbonate mixtures for example mixtures of dimethyl carbonate, diethyl carbonate and dimethoxy ethane.

Gallery

References

  1. ^ Shaikh, Abbas-Alli G.; Swaminathan Sivaram (1996). "Organic Carbonates". Chemical Reviews (American Chemical Society) 96 (3): 951–976. doi:10.1021/cr950067i. PMID 11848777. 
  2. ^ Zinc(II)-pyridine-2-carboxylate / 1-methyl-imidazole: a binary catalytic system for in the synthesis of cyclic carbonates from carbon dioxide and epoxides Arkivoc 2007 (iii) 151-163 (EA-2262DP) Thomas A. Zevaco, Annette Janssen, and Eckhard Dinjus Link
  3. ^ Schäffner, B.; Schäffner, F.; Verevkin, S. P.; Börner, A. (2010). "Organic Carbonates as Solvents in Synthesis and Catalysis". Chemical Reviews 110 (8): 4554. doi:10.1021/cr900393d. PMID 20345182.  edit

Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • carbonate — [ karbɔnat ] n. m. • 1787; de carbone ♦ Sel ou ester de l acide carbonique. ⇒ bicarbonate. Carbonate hydraté. ⇒ hydrocarbonate. Carbonate naturel de calcium (⇒ aragonite, calcaire, calcite, chaux) , de cuivre (⇒ azurite, malachite) , de fer (⇒… …   Encyclopédie Universelle

  • Carbonate d'éthylène — Général Nom IUPAC 1,3 dioxolan 2 one Synonymes carbonate d éthylène glycol dioxolone 2 …   Wikipédia en Français

  • carbonate — [kär′bə nit; ] also, and for v.always [, kär′bənāt΄] n. [Fr: see CARBON & ATE2] 1. a salt of carbonic acid containing the divalent, negative radical CO3 2. an uncharged ester of this acid vt. carbonated, carbonating …   English World dictionary

  • Carbonate — Carbonate,   Singular Carbonat das, (e)s, Salze und Ester der Kohlensäure …   Universal-Lexikon

  • Carbonate — Struktur des Carbonat Ions (oben blau markiert) mit 3 gleichwertigen Sauerstoff Atomen. Unten: Struktur der Kohlensäure Ester. Die Carbonat Gruppe ist blau markiert. R1 und R2 sind Alkyl oder Aryl Reste. Bei einem Halbester ist R2=H. Carbonate …   Deutsch Wikipedia

  • Carbonate — In chemistry, a carbonate is a salt or ester of carbonic acid.ApplicationsTo test for the presence of the carbonate anion in a salt, the addition of dilute mineral acid (e.g. hydrochloric acid) will yield carbon dioxide gas.Carbonate containing… …   Wikipedia

  • Ester — For other uses, see Ester (disambiguation). A carboxylic acid ester. R and R denote any alkyl or aryl group, respectively Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol …   Wikipedia

  • carbonate — carbonator, n. n. /kahr beuh nayt , nit/; v. /kahr beuh nayt /, n., v., carbonated, carbonating. n. 1. a salt or ester of carbonic acid. v.t. 2. to form into a carbonate. 3. to charge or impregnate with carbon dioxide: carbonated drinks. 4. to… …   Universalium

  • carbonate —    1. A salt or ester of carbonic acid; a compound containing the radical CO3–2, such as calcium carbonate, CaCO3.    2. A rock consisting mainly of carbonate minerals, such as limestone or dolomite [10] …   Lexicon of Cave and Karst Terminology

  • carbonate — I. noun Date: 1794 a salt or ester of carbonic acid II. transitive verb ( ated; ating) Date: 1805 1. to convert into a carbonate 2. to combine or infuse with carbon dioxide < carbonated beverages > • carbonation …   New Collegiate Dictionary

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”