Geminal halide hydrolysis

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Geminal halide hydrolysis is an organic reaction. The reactants are geminal dihalides with a water molecule or a hydroxide ion. The reaction yields ketones from secondary halides [1] [2] or aldehydes from primary halides. [3] [4]

Organic reaction chemical reactions involving organic compounds

Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions, substitution reactions, pericyclic reactions, rearrangement reactions, photochemical reactions and redox reactions. In organic synthesis, organic reactions are used in the construction of new organic molecules. The production of many man-made chemicals such as drugs, plastics, food additives, fabrics depend on organic reactions.

Geminal relationship between two atoms or functional groups

In chemistry, the descriptor geminal refers to the relationship between two atoms or functional groups that are attached to the same atom. The word comes from Latin gemini meaning "twins". A geminal diol, for example, is a diol attached to the same carbon atom, as in methanediol. Also the shortened prefix gem may be applied to a chemical name to denote this relationship, as in a gem-dibromide for "geminal dibromide".

Halocarbon compounds are chemicals in which one or more carbon atoms are linked by covalent bonds with one or more halogen atoms resulting in the formation of organofluorine compounds, organochlorine compounds, organobromine compounds, and organoiodine compounds. Chlorine halocarbons are the most common and are called organochlorides.

Contents

Reaction mechanism

The first part of the reaction mechanism consists of an ordinary nucleophilic aliphatic substitution to produce a gem-halohydrin:

In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical change occurs.

In organic chemistry a halohydrin is a functional group in which a halogen and a hydroxyl are bonded to adjacent carbon atoms, which otherwise bear only hydrogen or hydrocarbyl groups. The term only applies to saturated motifs, as such compounds like 2-chlorophenol would not normally be considered halohydrins. Megatons of some chlorohydrins, e.g. propylene chlorohydrin, are produced annually as precursors to polymers.

RCH(Cl)2 + KOH RCH(OH)Cl + KCl

The remaining halide is a good leaving group and this enables the newly created hydroxy group to convert into a carbonyl group by expelling the halide:

In chemistry, a leaving group is a molecular fragment that departs with a pair of electrons in heterolytic bond cleavage. Leaving groups can be anions or neutral molecules, but in either case it is crucial that the leaving group be able to stabilize the additional electron density that results from bond heterolysis. Common anionic leaving groups are halides such as Cl−, Br−, and I−, and sulfonate esters such as tosylate (TsO−). Fluoride (F−) functions as a leaving group in the nerve-agent sarin gas. Common neutral molecule leaving groups are water and ammonia. Leaving groups may also be positively charged cations (such as H+ released during the nitration of benzene); these are also known specifically as electrofuges.

RCH(OH)Cl Rearrangement gives R-CHO + HCl

Variations

Other functional groups can undergo similar hydrolysis reactions. For instance, geminal trihalides (e.g. benzotrichloride) can be partially hydrolyzed to acyl halides (e.g. benzoyl chloride) in a similar way. [5] Further hydrolysis yields carboxylic acids.

Functional group moiety that imparts a molecules characteristic chemical reactions; moiety that participates in similar chemical reactions in most molecules that contain it

In organic chemistry, functional groups are specific substituents or moieties within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction(s) regardless of the size of the molecule it is a part of. This allows for systematic prediction of chemical reactions and behavior of chemical compounds and design of chemical syntheses. Furthermore, the reactivity of a functional group can be modified by other functional groups nearby. In organic synthesis, functional group interconversion is one of the basic types of transformations.

Benzotrichloride chemical compound

Benzotrichloride, also known as trichlorotoluene is an organic compound with the formula C6H5CCl3. It is principally used as an intermediate in the preparation of other chemical products such as dyes.

Acyl halide any chemical compound having a halogen atom bonded to an acyl group

An acyl halide is a chemical compound derived from an oxoacid by replacing a hydroxyl group with a halide group.

See also

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Carboxylic acid oxoacid having the structure RC(=O)OH, used as a suffix in systematic name formation to denote the –C(=O)OH group including its carbon atom

A carboxylic acid is an organic compound that contains a carboxyl group. The general formula of a carboxylic acid is R–COOH, with R referring to the rest of the molecule. Carboxylic acids occur widely. Important examples include the amino acids and acetic acid. Deprotonation of a carboxyl group gives a carboxylate anion. Important carboxylate salts are soaps.

Ketone Class of organic compounds having structure RCOR´

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In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom by a methyl group. Methylation is a form of alkylation, with a methyl group, rather than a larger carbon chain, replacing a hydrogen atom. These terms are commonly used in chemistry, biochemistry, soil science, and the biological sciences.

A diol is a chemical compound containing two hydroxyl groups. An aliphatic diol is also called a glycol. This pairing of functional groups is pervasive, and many subcategories have been identified.

Acyl chloride any chemical compound having a chlorine atom bonded to a carboacyl group

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Allyl group functional group

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Favorskii rearrangement

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Hydroxylamine-<i>O</i>-sulfonic acid chemical compound

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References

  1. ↑ Marvel, C. S.; Sperry, W. M. (1928). "Benzophenone". Organic Syntheses. 8: 26. doi:10.15227/orgsyn.008.0026.
  2. ↑ Pond, F. J.; O. P., Maxwell; G. M., Norman (1899). "The Action of Sodium Methylate Upon Dibromides of Propenyl-Compounds and of Unsaturated Ketones". Journal of the American Chemical Society. 22 (11): 955–967. doi:10.1021/ja02061a002.
  3. ↑ Bill, J. C.; Tarbell, D. S. (1954). "o-Phthalaldehyde". Organic Syntheses. 34: 82. doi:10.15227/orgsyn.034.0082.
  4. ↑ Buck, Johannes S.; Zimmermann, F. J. (1938). "Protocatechualdehyde". Organic Syntheses. 18: 75. doi:10.15227/orgsyn.018.0075.
  5. ↑ Rossberg, Manfred; Lendle, Wilhelm; Pfleiderer, Gerhard; Tögel, Adolf; Dreher, Eberhard-Ludwig; Langer, Ernst; Rassaerts, Heinz; Kleinschmidt, Peter; Strack, Heinz; Cook, Richard; Beck, Uwe; Lipper, Karl-August; Torkelson, Theodore R.; Löser, Eckhard; Beutel, Klaus K.; Mann, Trevor (2006). "Chlorinated Hydrocarbons". Ullmann's Encyclopedia of Industrial Chemistry: 139. doi:10.1002/14356007.a06_233.pub2. ISBN   3527306730.
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