Nucleophilic addition

	Email		Print
	Bookmark		Link

Nucleophilic addition

In organic chemistry

Organic chemistry

Organic chemistry is a discipline within chemistry which involves the science study of the structure, properties, composition, chemical reaction, and preparation of chemical compounds that contain carbon....
, a nucleophilic addition reaction is an addition reaction

Addition reaction

An addition reaction, in organic chemistry, is in its simplest terms an organic reaction where two or more molecules combine to form a larger one....
where in a chemical compound

Chemical compound

A chemical compound is a Chemical substance consisting of two or more different chemical element Chemical bond together in a fixed mass ratio that can be split into simpler substances....
a p bond is removed by the creation of two new covalent bond

Covalent bond

A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, or between atoms and other covalent bonds....
s by the addition of a nucleophile

Nucleophile

In chemistry, a nucleophile is a reagent that forms a chemical bond to its reaction partner by donating both bonding electrons. Because nucleophiles donate electrons, they are by definition Lewis bases ....
.

Addition reactions are limited to chemical compounds that have multiple-bonded atoms:

tion reactions of a nucleophile to carbon - hetero double bonds such as C=O or CN triple bond show a wide variety.

Discussion

Ask a question about 'Nucleophilic addition'

Start a new discussion about 'Nucleophilic addition'

Answer questions from other users

Full Discussion Forum

Encyclopedia

In organic chemistry

Organic chemistry

Addition reaction

An addition reaction, in organic chemistry, is in its simplest terms an organic reaction where two or more molecules combine to form a larger one....
where in a chemical compound

Chemical compound

Covalent bond

Nucleophile

molecules with carbon - hetero multiple bonds like carbonyl
Carbonyl

In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double bond to an oxygen atom : C=O.The term carbonyl can also refer to carbon monoxide as a ligand in an inorganic or organometallic complex ; in this situation, carbon is triple-bonded to oxygen : C=O....
s, imine
Imine

An imine is a functional group or chemical compound containing a carbon?nitrogen double bond . Due to their diverse reactivity, imines are common substrates in a wide variety of transformations....
s or nitrile
Nitrile

A nitrile is any organic compound which has a -Carbon=Nitrogen functional group. The -C=N functional group is called a nitrile group....
s
molecules with carbon - carbon double bonds or triple bonds

Addition to carbon - hetero double bonds

Addition reactions of a nucleophile to carbon - hetero double bonds such as C=O or CN triple bond show a wide variety. These bonds are polar

Polar bond

Polar bond may refer to:Polar bond* Chemical polarity* Covalent bond* Bond dipole moment* Partial charge* Dipoles#Molecular dipoles* Electronegativity...
(have a large difference in electronegativity

Electronegativity

Electronegativity, symbol χ, is a chemical property that describes the ability of an atom to attract electrons towards itself in a covalent bond....
between the two atoms) consequently carbon carries a partial positive charge. This makes this atom the primary target for the nucleophile.

This type of reaction is also called a 1,2 nucleophilic addition. The stereochemistry

Stereochemistry

Stereochemistry, a subdiscipline of chemistry, involves the study of the relative spatial arrangement of atoms within molecules. An important branch of stereochemistry is the study of chirality molecules ....
of this type of nucleophilic attack is not an issue, when both alkyl substituents are dissimilar and there are not any other controlling issues such as chelation

Chelation

Chelation is the binding or complex of a bi- or multidentate ligand. These ligands, which are often organic compounds, are called chelants, chelators, chelating agents, or sequestration....
with a Lewis acid

Lewis acid

A Lewis acid is a chemical compound, A, that can accept a pair of electrons from a Lewis base, B, that acts as an electron-pair donor, forming an adduct, AB.Gilbert N....
, the reaction product is a racemate. Addition reactions of this type are numerous. When the addition reaction is accompanied by an elimination the reaction type is nucleophilic acyl substitution

Nucleophilic acyl substitution

Nucleophilic acyl substitution describes the substitution reaction involving nucleophiles and acyl compounds. Acyl compounds are carboxylic acid derivatives including esters, amides and acid halides....
or an addition-elimination reaction.

Carbonyls

With a carbonyl compound as an electrophile, the nucleophile can be:

water
Water

Water is a common chemical substance that is essential for the survival of all known forms of life. In typical usage, water refers only to its liquid form or States of matter, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam....
in hydration
Hydration

Hydration may refer to:* Hydration reaction, a chemical addition reaction* Mineral hydration, an inorganic chemical reaction where water is added to the crystal structure of a mineral...
to a geminal
Geminal

In chemistry, the term geminal refers to the relationship between two functional groups that are attached to the same atom. The prefix gem is applied to a chemical name to denote this relationship, as in a gem-dibromide....
diol
Diol

A diol or glycol is a chemical compound containing two hydroxyl groups Vicinal diols have hydroxyl groups attached to adjacent atoms. Examples of vicinal diol compounds are ethylene glycol and propylene glycol....
(hydrate)
an alcohol
Alcohol

In chemistry, an alcohol is any organic compound in which a hydroxyl Functional group is bound to a carbon atom of an alkyl or substituted alkyl group....
in acetalisation
Acetalisation

Acetalisation is an organic reaction that involves the formation of an acetal or ketal. One way of acetal formation is the nucleophilic addition of an alcohol to a ketone or an aldehyde....
to an acetal
Acetal

An acetal is a molecule with two single bonded oxygens attached to the same carbon atom.Traditional usages distinguish ketal from acetal . Current accepted terminology classifies ketals as a subset of acetals....
an hydride
Hydride

Hydride is the name given to the Electric charge ion of hydrogen, H-. Although this ion does not exist except in extraordinary conditions, the term hydride is widely applied to describe Chemical compound of hydrogen with other chemical element, particularly those of Periodic table group 1–16....
in reduction
Reducing agent

A reducing agent is the element or compound in a redox reaction that reduces another Chemical species. In doing so, it becomes oxidized, and is therefore the electron donor in the redox....
to an alcohol
Alcohol

In chemistry, an alcohol is any organic compound in which a hydroxyl Functional group is bound to a carbon atom of an alkyl or substituted alkyl group....
an amine
Amine

Amines are organic compounds and functional groups that contain a base nitrogen atom with a lone pair. Amines are derivative s of ammonia, wherein one or more hydrogen atoms are replaced by organic substituents such as alkyl and aryl groups....
with formaldehyde and a carbonyl compound in the Mannich reaction
Mannich reaction

The Mannich reaction is an organic reaction which consists of an amino alkylation of an acidic proton placed next to a carbonyl functional group with formaldehyde and ammonia or any primary or secondary amine....
an enolate ion in an aldol reaction
Aldol reaction

The aldol reaction is a carbon-carbon bond formation chemical reaction in organic chemistry. In its usual form, it involves the nucleophilic addition of a ketone enolate to an aldehyde to form a Hydroxy ketone, or "aldol" , a structural unit found in many biomolecule and pharmaceuticals....
or Baylis-Hillman reaction
Baylis-Hillman reaction

The Baylis-Hillman reaction is an organic reaction of an aldehyde and an a,?-saturation electron-withdrawing group catalyzed by DABCO to give an allyl alcohol ....
an organometallic nucleophile
Nucleophile

In chemistry, a nucleophile is a reagent that forms a chemical bond to its reaction partner by donating both bonding electrons. Because nucleophiles donate electrons, they are by definition Lewis bases ....
in the Grignard reaction
Grignard reaction

The Grignard reaction, named after the French chemist Fran?ois Auguste Victor Grignard, is an organometallic chemistry chemical reaction in which alkyl- or aryl-magnesium halides , act as nucleophiles, attack electrophilic carbon atoms that are present within polar bonds to yield a carbon-carbon bond , thus altering hybridization about the r...
or the related Barbier reaction
Barbier reaction

The Barbier reaction is an organic reaction between an alkyl halide and a carbonyl group as an electrophilic substrate in the presence of aluminium, zinc, indium, tin or its salts....
or a Reformatskii reaction
Reformatskii reaction

The Reformatsky reaction is an organic reaction which condensation reaction aldehydes 1 with a-halo esters 2 with metallic zinc to form ?-hydroxy-esters 3....
ylide
Ylide

An ylid or ylide is a electric charge molecule with a positive and a negative charge on adjacent atoms. They appear in organic chemistry as reagents or reactive intermediates....
s such as a Wittig reagent or the Corey-Chaykovsky reagent or a-silyl carbanions in the Peterson olefination
Peterson olefination

The Peterson olefination is the chemical reaction of a-silyl carbanions 1 with ketones to form a ?-hydroxysilane 2 which eliminates to form alkenes 3....
a phosphonate carbanion in the Horner-Wadsworth-Emmons reaction
Horner-Wadsworth-Emmons reaction

The Horner-Wadsworth-Emmons reaction is the chemical reaction of stabilized phosphonate carbanions with aldehydes to produce predominantly E-alkenes....
a pyridine zwitterion in the Hammick reaction
Hammick reaction

The Hammick reaction, named after Dalziel Hammick, is a chemical reaction described as a thermal decarboxylation of a-picolinic acid carboxylic acid in the presence of carbonyl compounds to form 2-pyridine-carbinols....
an acetylide in the Favorskii reaction
Favorskii reaction

The Favorskii reaction , named for the Russian chemist Alexei Yevgrafovich Favorskii, is a special case of nucleophilic attack on a carbonyl group involving a terminal alkyne with carbon acid....

Nitriles

With nitrile

Nitrile

A nitrile is any organic compound which has a -Carbon=Nitrogen functional group. The -C=N functional group is called a nitrile group....
electrophiles nucleophilic addition take place by:

hydrolysis of a nitrile
Nitrile

A nitrile is any organic compound which has a -Carbon=Nitrogen functional group. The -C=N functional group is called a nitrile group....
to an amide
Amide

In chemistry, an amide is one of three kinds of compounds:* the organic chemistry functional group characterized by a carbonyl group linked to a nitrogen atom , or a compound that contains this functional group ; or...
or a carboxylic acid
Carboxylic acid

Carboxylic acids are organic acids characterized by the presence of a carboxyl group, which has the Chemical formula -COH, usually written -COOH or -CO2H....
organozinc nucleophiles in the Blaise reaction
Blaise reaction

The Blaise reaction is an organic reaction that forms a ?-ketoester from the reaction of zinc metal with a haloketone and a nitrile. The final intermediate is a metaloimine, which is hydrolyzed to give the desired ?-ketoester....
alcohol
Alcohol

In chemistry, an alcohol is any organic compound in which a hydroxyl Functional group is bound to a carbon atom of an alkyl or substituted alkyl group....
s in the Pinner reaction
Pinner reaction

The Pinner reaction is an organic reaction of a nitrile with an alcohol under acid catalysis for instance hydrochloric acid. The product formed is the hydrochloric acid salt of an imino ester or an alkyl imidate, which sometimes is called a Pinner salt....
.
the (same) nitrile a-carbon in the Thorpe reaction
Thorpe reaction

The Thorpe reaction is a chemical reaction described as a self-condensation of aliphatic nitriles catalyzed by Base to form enamines. The reaction was discovered by Jocelyn Field Thorpe....
. The intramolecular version is called the Thorpe-Ziegler reaction.

Imines and other

With imine

Imine

An imine is a functional group or chemical compound containing a carbon?nitrogen double bond . Due to their diverse reactivity, imines are common substrates in a wide variety of transformations....
electrophiles nucleophilic addition take place by:

hydrides to amines in the Eschweiler-Clarke reaction
Eschweiler-Clarke reaction

The Eschweiler-Clarke reaction is a chemical reaction whereby a primary amine is methylated using excess formic acid and formaldehyde. Reductive amination reactions such as this one will not produce quaternary ammonium salts, but instead will stop at the tertiary amine stage....
water to carbonyls in the Nef reaction
Nef reaction

The Nef reaction is an organic reaction describing the acid catalysis hydrolysis of a salt of a primary or secondary nitroalkane to an aldehyde or a ketone and nitrous oxide ....

With miscellaneous electrophiles:

addition of an alcohol
Alcohol

In chemistry, an alcohol is any organic compound in which a hydroxyl Functional group is bound to a carbon atom of an alkyl or substituted alkyl group....
to an isocyanate
Isocyanate

Isocyanate is the functional group of atoms ?N=C=O , not to be confused with the cyanate functional group which is arranged as ?O?C=N....
to form a urethane
Urethane

Urethane can refer to*Carbamates, compounds with the functional group RONHR'*ethyl carbamate, the trivial name of which is urethane*polyurethane in colloquial usage...

Nucleophiles attack carbonyl centers from a specific angle called the Bürgi-Dunitz angle

Bürgi-Dunitz angle

The B?rgi-Dunitz angle describes the angle of attack of a nucleophile at a carbonyl center. The angle was named after Hans-Beat B?rgi and Jack D....
.

Addition to carbon - carbon double bonds

The driving force for the addition to alkenes is the formation of a nucleophile

Nucleophile

Covalent bond

A covalent bond is a form of chemical bonding that is characterized by the sharing of pairs of electrons between atoms, or between atoms and other covalent bonds....
with an electron-poor unsaturated

Saturation (chemistry)

In chemistry, saturation has five different meanings:#In physical chemistry, saturation is the point at which a solution of a substance can dissolve no more of that substance and additional amounts of it will appear as a Precipitation ....
system -C=C- (step 1). The negative charge on X is transferred to the carbon - carbon bond.

In step 2 the negatively charged carbanion

Carbanion

A carbanion is an anion in which carbon has an unshared pair of electrons and bears a negative charge usually with three substituents for a total of eight valence electrons ....
combines with (Y) that is electron-poor to form the second covalent bond.

Ordinary alkenes are not susceptible to a nucleophilic attack (apolar bond). Styrene

Styrene

Styrene, also known as vinyl benzene as well as many other names , is an organic compound with the chemical formula C6H5CH=CH2....
reacts in toluene

Toluene

Toluene, also known as methylbenzene or phenylmethane, is a clear, Water -insoluble liquid with the typical smell of paint thinners, redolent of the sweet smell of the related compound benzene....
with sodium

Sodium

Sodium is an element which has the symbol Na , atomic number 11, atomic mass 23 amu , and a common oxidation number +1. Sodium is a soft, silvery white, highly reactive element and is a member of the alkali metals within "group 1" ....
to 1,3-diphenylpropane through the intermediate carbanion:

Another exception to the rule is found in the Varrentrapp reaction

Varrentrapp reaction

The Varrentrapp reaction is an organic reaction involving the chemical decomposition of an a,?-unsaturated carboxylic acid into two other acid fragments by action of molten alkali....
. Fullerene

Fullerene

Fullerene are a family of carbon Allotropy, molecules composed entirely of carbon, in the form of a hollow sphere, ellipsoid, cylinder , or plane....
s have unusual double bond reactivity and additions such has the Bingel reaction

Bingel reaction

The Bingel reaction in fullerene chemistry is a fullerene cyclopropane to a methanofullerene first discovered by C. Bingel in 1993 with the bromo derivative of diethyl malonate in the presence of a base such as sodium hydride or DBU ....
are more frequent.

When X is a carbonyl group like C=O or COOR or a cyanide

Cyanide

A cyanide is any chemical compound that contains the nitrile , which consists of a carbon atom chemical bond to a nitrogen atom. Inorganic cyanides are hydrogen cyanide salts in which cyanide is generally the anion CN-....
group (CN), the reaction type is a conjugate addition reaction. The substituent X helps to stabilize the negative charge on the carbon atom by its inductive effect

Inductive effect

The inductive effect in chemistry is an experimentally observable effect of the transmission of charge through a chain of atoms in a molecule by electrostatic induction....
.

In addition when Y-Z is an active hydrogen compound the reaction is known as a Michael reaction

Michael reaction

The Michael reaction or Michael addition is the nucleophilic addition of a carbanion to an ?,?-unsaturated carbonyl compound. It belongs to the larger class of conjugate additions....
.

Perfluorinated alkenes (alkenes that have all hydrogens replaced by fluorine

Fluorine

Fluorine is the chemical element with the symbol F and atomic number 9. Fluorine forms a single bond with itself in elemental form, resulting in the diatomic F2 molecule....
) are highly prone to nucleophilic addition, for example by fluoride ion from caesium fluoride

Caesium fluoride

Caesium fluoride , is an ionic compound usually found as a hygroscopic white solid. It is more soluble and more readily Dissociation than sodium fluoride or potassium fluoride....
or silver(I) fluoride

Silver(I) fluoride

Silver fluoride , also known as argentous fluoride and silver monofluoride, is a compound of silver and fluorine. It is a ginger-coloured solid, melting point 435 ?C, which blackens on exposure to moist air....
to give a perfluoroalkyl anion.