What is Glycol?

Information about Glycol

A diol or glycol is a chemical compound containing two hydroxyl groups (-OH groups). Vicinal diols have hydroxyl groups attached to adjacent atoms. Examples of vicinal diol compounds are ethylene glycol and propylene glycol. Geminal diols have hydroxyl groups bonded to the same atom. In general, organic geminal diols readily dehydrate to form a carbonyl group. For example, carbonic acid ((HO)₂C=O) is unstable and has a tendency to convert to carbon dioxide (CO₂) and water (H₂O). Nevertheless, in rare situations the chemical equilibrium is in favor of the geminal diol. For example, when formaldehyde (H₂C=O) is dissolved in water the geminal diol (H₂C(OH)₂), methanediol, is favored.

Examples of diols in which the hydroxyl functional groups are more widely separated include 1,4-butanediol and bisphenol A.

Synthesis of diols

Because diols are a common functional group arrangement, numerous methods of preparation have been developed.

Vicinal diols can be produced from the oxidation of alkenes, usually with dilute acidic potassium permanganate, also known as potassium manganate(VII). Using alkaline potassium manganate(VII) produces a colour change from clear deep purple to clear green; acidic potassium manganate(VII) turns clear colourless.
Osmium tetroxide can similarly be used to oxidize alkenes to vicinal diols.
A chemical reaction called Sharpless bishydroxylation can be used to produce chiral diols from alkenes using an osmate reagent and a chiral catalyst.
Another method is the Woodward cis-hydroxylation.
In the Prins reaction 1,3-diols can be formed in a reaction between an alkene and formaldehyde.

Reactions

A diol reacts like an alcohol, such as esterification and ether formation.
Diols such as ethylene glycol are used as co-monomers in polymerization reactions forming polymers including some polyesters and polyurethanes. A different monomer with two identical functional groups, such as a dioyl dichloride or dioic acid is required to continue the process of polymerization through repeated esterification processes.
In glycol cleavage, the C-C bond in a vicinal diol is cleaved with formation of ketone or aldehyde functional groups.

Synthesis

Its industrial synthesis starts with acetylene, which is reacted with two molecules of formaldehyde to form 1,4-butynediol, also
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Bisphenol A is a chemical compound containing two phenol functional groups. It belongs to the phenol class of aromatic organic compounds. It is widely prepared and sold and various important polymers/plastics are made from it.
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Redox (shorthand for reduction/oxidation reaction) describes all chemical reactions in which atoms have their oxidation number (oxidation state) changed.

This can be either a simple redox process such as the oxidation of carbon to yield carbon dioxide, or the
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alkene, olefin, or olefine is an unsaturated chemical compound containing at least one carbon-to-carbon double bond. The simplest alkenes, with only one double bond and no other functional groups, form a homologous series of hydrocarbons with the general formula
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ACID (Atomicity, Consistency, Isolation, Durability) is a set of properties that guarantee that database transactions are processed reliably. In the context of databases, a single logical operation on the data is called a transaction.
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Potassium permanganate is the chemical compound KMnO₄. In this salt, manganese is in the +7 oxidation state. The salt is also known as "permanganate of potash." The permanganate ion is a strong oxidizing agent.
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Osmium tetroxide is the chemical compound with the formula OsO₄. The compound is noteworthy for its many uses, despite the rarity of osmium. It also has a number of interesting properties, one being that the solid is volatile.
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Sharpless asymmetric dihydroxylation (also called the Sharpless bishydroxylation) is the chemical reaction of an alkene with osmium tetroxide in the presence of a chiral quinine ligand to form a vicinal diol.
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The term chiral (pronounced /ˈkaɪɹ(ə)l̩/) is used to describe an object that is non-superimposable on its mirror image. In terms of chemistry, such objects are usually molecules.
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A reactant or reagent is a substance consumed during a chemical reaction.^[1] Solvents and catalysts, although they are involved in the reaction, are usually not referred to as reactants.
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catalysis is the acceleration (increase in rate) of a chemical reaction by means of a substance called a catalyst, which is itself not consumed by the overall reaction.
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The Woodward cis-hydroxylation is the chemical reaction of alkenes with iodine and silver acetate in wet acetic acid to form cis-diols. ^[1] ^[2] The reaction is named after its discoverer, Robert Burns Woodward.
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The Prins reaction is an organic reaction consisting of an electrophilic addition of an aldehyde or ketone to an alkene or alkyne followed by capture of a nucleophile ^[1] ^[2] ^[3].
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alcohol is any organic compound in which a hydroxyl group (-OH) is bound to a carbon atom of an alkyl or substituted alkyl group. The general formula for a simple acyclic alcohol is C_nH_2n+1OH.
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