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A carbonate ester (organic carbonate or organocarbonate) is an ester of carbonic acid. This functional group consists 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. Monomers of polycarbonate (e.g. Lexan) are linked by carbonate groups. These polycarbonates are used in eyeglass lenses, compact discs, and bulletproof glass. Small carbonate esters like dimethyl carbonate, and ethylene and propylene carbonate are used as solvents. Dimethyl carbonate is a mild methylating agent as well. The chemistry of carbonate esters has been reviewed. ==Types== Carbonate esters can be divided into three categories by their structures. The first and general case is the dialkyl or diaryl carbonate that comprises a carbonate group with two R substituents. The simplest members of this class include dimethyl carbonate and diphenyl carbonate: File:Dimethyl carbonate Structural Formulae.svg|Dimethyl carbonate File:Diphenyl_carbonate.png|Diphenyl carbonate Instead of terminal alkyl or aryl R-groups, two carbonate groups can be linked by an aliphatic or aromatic bifunctional group. For example, poly(propylene carbonate) and poly(bisphenol A carbonate) (Lexan): File:Polypropylene Carbonate 1.PNG|Poly(propylene carbonate) File:Lexan.png|Poly(bisphenol A carbonate) (Lexan) Alternatively, the carbonate groups can be linked by a 2- or 3-carbon bridge, such as ethylene carbonate and trimethylene carbonate; substituents, e.g. CH3 for propylene carbonate are possible too: File:Ethylene carbonate.png|Ethylene carbonate File:Trimethylene_carbonate.png|Trimethylene carbonate 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「carbonate ester」の詳細全文を読む スポンサード リンク
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