1845, DIETHYL ETHER ANESTHETIC IS USED IN JEFFERSON

Today, The Grandma has been reading about diethyl ether, the organic compound, that was used for childbirth for the first time by Dr. Crawford Long in Jefferson, Georgia, on a day like today in 1845.

Diethyl ether, or simply ether, is an organic compound with the chemical formula (CH3CH2)2O, sometimes abbreviated as Et2O. It is a colourless, highly volatile, sweet-smelling (ethereal odour), extremely flammable liquid. It belongs to the ether class of organic compounds. It is a common solvent. It was formerly used as a general anesthetic.

Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises: Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%.

    2 CH3CH2OH → (CH3CH2)2O + H2O

Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis.

The dominant use of diethyl ether is as a solvent. One particular application is in the production of cellulose plastics such as cellulose acetate.

It is a common solvent for the Grignard reaction in addition to other reactions involving organometallic reagents. These uses exploit its basicity. Diethyl ether is a popular non-polar solvent in liquid-liquid extraction. As an extractant, it is immiscible with and less dense than water.

Although immiscible, it has significant solubility in water (6.05 g/(100 ml) at 25 °C) and dissolves 1.5 g/(100 g) (1.0 g/(100 ml)) water at 25 °C.

Diethyl ether has a high cetane number of 85–96 and, in combination with petroleum distillates for gasoline and diesel engines, is used as a starting fluid because of its high volatility and low flash point. Ether starting fluid is sold and used in countries with cold climates, as it can help with cold starting an engine at sub-zero temperatures. For the same reason it is also used as a component of the fuel mixture for carbureted compression ignition model engines.

A cytochrome P450 enzyme is proposed to metabolize diethyl ether.

Diethyl ether inhibits alcohol dehydrogenase, and thus slows the metabolism of ethanol. It also inhibits metabolism of other drugs requiring oxidative metabolism. For example, diazepam requires hepatic oxidization whereas its oxidized metabolite oxazepam does not.

Diethyl ether is extremely flammable and may form explosive vapour/air mixtures.

Since ether is heavier than air it can collect low to the ground and the vapour may travel considerable distances to ignition sources. Ether will ignite if exposed to an open flame, though due to its high flammability, an open flame is not required for ignition. Other possible ignition sources include –but are not limited to– hot plates, steam pipes, heaters, and electrical arcs created by switches or outlets.

Vapour may also be ignited by the static electricity which can build up when ether is being poured from one vessel into another. The autoignition temperature of diethyl ether is 160 °C. The diffusion of diethyl ether in air is 9.18 × 10−6 m2/s.

Ether is sensitive to light and air, tending to form explosive peroxides. Ether peroxides have a higher boiling point than ether and are contact explosives when dry.

Commercial diethyl ether is typically supplied with trace amounts of the antioxidant butylated hydroxytoluene (BHT), which reduces the formation of peroxides. Storage over sodium hydroxide precipitates the intermediate ether hydroperoxides. Water and peroxides can be removed by either distillation from sodium and benzophenone, or by passing through a column of activated alumina.

Due to its application in the manufacturing of illicit substances, it is listed in the Table II precursor under the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances as well as substances such as acetone, toluene and sulfuric acid.

The compound may have been synthesised by either Jābir ibn Hayyān in the 8th century or Ramon Llull in 1275. 

It was synthesised in 1540 by Valerius Cordus, who called it sweet oil of vitriol (oleum dulce vitrioli) –the name reflects the fact that it is obtained by distilling a mixture of ethanol and sulfuric acid (then known as oil of vitriol)– and noted some of its medicinal properties.

At about the same time, Paracelsus discovered the analgesic properties of the molecule in dogs. The name ether was given to the substance in 1729 by August Sigmund Frobenius.

It was considered to be a sulfur compound until the idea was disproved in about 1800.

The synthesis of diethyl ether by a reaction between ethanol and sulfuric acid has been known since the 13th century.

More information: PubChem

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