Metylestern

Metylestern is a nonstandard or regional term sometimes used to refer to methyl esters, a class of organic compounds formed from methanol and carboxylic acids. In contemporary English-language chemistry, the preferred term is methyl ester; metylestern may appear in texts influenced by other languages where forms like metylester are common. Methyl esters have the general formula R-COO-CH3 and are produced by esterification of carboxylic acids with methanol or by transesterification of esters with methanol.

Common examples include methyl formate (HCOOCH3) and methyl acetate (CH3COOCH3). Fatty acid methyl esters (FAMEs) are important products in biodiesel production. Methyl esters are typically colorless liquids or solids at room temperature, with properties that vary with the R group. They are generally more volatile and less polar than the parent carboxylic acids from which they are derived.

Synthesis methods include acid-catalyzed esterification of carboxylic acids with methanol, often aided by removal of water to shift the equilibrium toward ester formation. Transesterification of triglycerides with methanol yields fatty acid methyl esters and glycerol, commonly using base catalysts such as sodium or potassium hydroxide. Industrial processes emphasize purification to remove residual methanol and catalysts.

Applications of methyl esters span solvents, plasticizers, flavors and fragrances, and, most notably, biodiesel fuel components. Safety considerations include methanol’s toxicity and flammability; methyl esters themselves are typically flammable with varying toxicity. Environmental notes indicate many methyl esters are readily biodegradable, but handling requires appropriate ventilation and protective measures to minimize exposure.