A diol or glycol is a chemical compound containing two hydroxyl groups (-OH groups) ^[1] Vicinal diols have hydroxyl groups attached to adjacent atoms. Ethylene glycol ( monoethylene glycol ( MEG) 12-ethanediol, IUPAC name: ethane-12-diol) is an Alcohol with two -OH A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. Hydroxyl in Chemistry stands for a molecule consisting of an Oxygen atom and a Hydrogen atom connected by a Covalent bond. In Chemistry vicinal (from Latin vicinus = neighbour stands for any two Functional groups bonded to two adjacent Carbon atoms Examples of vicinal diol compounds are ethylene glycol and propylene glycol. Ethylene glycol ( monoethylene glycol ( MEG) 12-ethanediol, IUPAC name: ethane-12-diol) is an Alcohol with two -OH Propylene glycol, known also by the systematic name propane-12-diol is an Organic compound (a Diol Alcohol) usually a faintly sweet odorless and Geminal diols have hydroxyl groups bonded to the same atom. In Chemistry, the term geminal (from Latin gemini = twins refers to the relationship between two Functional groups that are attached to the same In general, organic geminal diols readily dehydrate to form a carbonyl group. In Chemistry, a dehydration reaction is usually defined as a chemical reaction that involves the loss of water from the reacting molecule In Organic chemistry, a carbonyl group is a Functional group composed of a Carbon Atom double-bonded to an Oxygen For example, carbonic acid ((HO)₂C=O) is unstable and has a tendency to convert to carbon dioxide (CO₂) and water (H₂O). Carbonic acid (ancient name acid of air or aerial acid) has the formula H2CO3 Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Nevertheless, in rare situations the chemical equilibrium is in favor of the geminal diol. In a Chemical process, chemical equilibrium is the state in which the chemical activities or Concentrations of the reactants and products have no net change For example, when formaldehyde (H₂C=O) is dissolved in water the geminal diol (H₂C(OH)₂), methanediol, is favored. Formaldehyde is a Chemical compound with the formula H2CO It is the simplest Aldehyde —an organic compound containing a terminal Carbonyl Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as Methanediol, also known as dihydroxymethane, formaldehyde monohydrate, or methylene glycol is a Chemical compound that occurs primarily

Examples of diols in which the hydroxyl functional groups are more widely separated include 1,4-butanediol and bisphenol A. Bisphenol A, commonly abbreviated as BPA, is an Organic compound with two Phenol Functional groups It is a difunctional building block of

Contents 1 Synthesis of diols 2 Reactions 3 See also 4 References

Synthesis of diols

Because diols are a common functional group arrangement, numerous methods of preparation have been developed. In Organic chemistry, functional groups are specific groups of Atoms within Molecules that are responsible for the characteristic Chemical reactions

• Vicinal diols can be produced from the oxidation of alkenes, usually with dilute acidic potassium permanganate, also known as potassium manganate(VII). Redox (shorthand for reduction-oxidation reaction describes all Chemical reactions in which atoms have their Oxidation number ( Oxidation state In Organic chemistry, an alkene, olefin, or olefine is an unsaturated Chemical compound containing at least one Carbon In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are Potassium permanganate is the Chemical compound K[[manganese Mn]] O 4 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. Osmium tetroxide is the Chemical compound with the formula OsO4
• hydrogen peroxide reacts with an alkene to the epoxide and then by saponification to the diol for example in the synthesis of trans-cyclohexanediol batch ^[2] or by microreactor ^[3]:

• A chemical reaction called Sharpless asymmetric dihydroxylation can be used to produce chiral diols from alkenes using an osmate reagent and a chiral catalyst. Hydrogen peroxide (H2O2 is a very pale blue liquid which appears colorless in a dilute solution slightly more Viscous than water An epoxide is a cyclic Ether with only three ring atoms This ring approximately is an Equilateral triangle, i Saponification is the Hydrolysis of an Ester under basic conditions to form an Alcohol and the Salt of a Carboxylic acid A microreactor or microstructured reactor or microchannel reactor is a device in which Chemical reactions take place in a confinement with typical lateral Sharpless asymmetric dihydroxylation (also called the Sharpless bishydroxylation) is the Chemical reaction of an Alkene with Osmium tetroxide The term chiral (pronounced /ˈkaɪɹ(əl̩/ is used to describe an object that is non- superimposable on its mirror image A reagent or reactant is a substance or compound consumed during a Chemical reaction. Catalysis is the process in which the rate of a Chemical reaction is increased by means of a Chemical substance known as a catalyst
• Another method is the Woodward cis-hydroxylation (cis diol) and the related Prévost reaction (anti diol), depicted below, which both use iodine and the silver salt of a carboxylic acid. The Woodward cis-hydroxylation is the Chemical reaction of Alkenes with Iodine and Silver acetate in wet Acetic acid to form cis-diols The Prévost reaction is Chemical reaction in which an Alkene is converted by Iodine and the Silver Salt of Benzoic acid

• In the Prins reaction 1,3-diols can be formed in a reaction between an alkene and formaldehyde. Prins reaction is an Organic reaction consisting of an Electrophilic addition of an Aldehyde or Ketone to an Alkene or Alkyne In Organic chemistry, an alkene, olefin, or olefine is an unsaturated Chemical compound containing at least one Carbon Formaldehyde is a Chemical compound with the formula H2CO It is the simplest Aldehyde —an organic compound containing a terminal Carbonyl

Reactions

• A diol reacts like an alcohol, such as esterification and ether formation. In Chemistry, an alcohol is any Organic compound in which a Hydroxyl group ( - O[[hydrogen H]]) is bound to a Carbon Esterification is the general name for a Chemical reaction in which two reactants (typically an alcohol and an acid form an Ester as the reaction product Ether is a class of Organic compounds which contain an ether group — an Oxygen Atom connected to two (substituted Alkyl
• Diols such as ethylene glycol are used as co-monomers in polymerization reactions forming polymers including some polyesters and polyurethanes. Ethylene glycol ( monoethylene glycol ( MEG) 12-ethanediol, IUPAC name: ethane-12-diol) is an Alcohol with two -OH A monomer (from Greek mono "one" and meros "part" is a small Molecule that may become chemically bonded to other In Polymer chemistry, polymerization is a process of reacting Monomer Molecules together in a Chemical reaction to form three-dimensional networks A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds Polyester is a category of Polymers which contain the Ester Functional group in their main chain A polyurethane, commonly abbreviated PU, is any Polymer consisting of a chain of organic units joined by urethane links 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. Glycol cleavage is a specific type of organic chemistry Oxidation. In Chemistry vicinal (from Latin vicinus = neighbour stands for any two Functional groups bonded to two adjacent Carbon atoms

See also

• Alcohols, chemical compounds with one hydroxyl group
• Triols, chemical compounds with three hydroxyl group
• Polyols, chemical compounds with multiple hydroxyl groups

References

The Journal of Organic Chemistry (abbreviated as J Org Chem or JOC) is a Scientific journal for original contributions of fundamental A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.

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