View source for Functional group

{{Short description|Group of atoms giving a molecule characteristic properties}}
{{Other uses}}
{{More citations needed|date=August 2016}}
[[File:Benzyl acetate - functional groups and moieties.svg|thumb|150px|Example functional groups of [[benzyl acetate]]:
{{legend-line|solid red|[[Ester]] group}}
{{legend-line|dashed green|[[Acetyl]] group}} {{legend-line|dashed orange|[[Benzyl alcohol|Benzyloxy]] group}}
]]

In [[organic chemistry]], a '''functional group''' is a [[substituent]] or [[moiety (chemistry)|moiety]] in a [[molecule]] that causes the molecule's characteristic [[chemical reaction]]s. The same functional group will undergo the same or similar chemical reactions regardless of the rest of the molecule's composition.<ref>[[Compendium of Chemical Terminology]] (IUPAC "Gold Book") [http://goldbook.iupac.org/html/F/F02555.html functional group] {{Webarchive|url=https://web.archive.org/web/20190516163117/http://goldbook.iupac.org/html/F/F02555.html |date=2019-05-16 }}</ref><ref>{{March3rd}}</ref> This enables systematic prediction of chemical reactions and behavior of [[chemical compound]]s and the design of [[chemical synthesis]]. The [[Reactivity (chemistry)|reactivity]] of a functional group can be modified by other functional groups nearby. [[Functional group interconversion]] can be used in [[retrosynthetic analysis]] to plan [[organic synthesis]].

A functional group is a group of atoms in a molecule with distinctive [[Chemical property|chemical properties]], regardless of the other [[atom]]s in the molecule. The atoms in a functional group are linked to each other and to the rest of the molecule by [[covalent bond]]s. For repeating units of [[polymer]]s, functional groups attach to their [[Chemical polarity|nonpolar]] core of [[carbon]] atoms and thus add chemical character to carbon chains. Functional groups can also be [[Ionization|charged]], e.g. in [[carboxylate]] salts ({{chem2|\sCOO-}}), which turns the molecule into a [[polyatomic ion]] or a [[coordination complex|complex ion]]. Functional groups binding to a central atom in a [[coordination complex]] are called ''[[ligand]]s''. Complexation and [[solvation]] are also caused by specific interactions of functional groups. In the common rule of thumb "like dissolves like", it is the shared or mutually well-interacting functional groups which give rise to [[solubility]]. For example, [[sugar]] dissolves in water because both share the [[Hydroxy group|hydroxyl]] functional group ({{chem2|\sOH}}) and hydroxyls interact strongly with each other. Plus, when functional groups are more [[Electronegativity|electronegative]] than atoms they attach to, the functional groups will become polar, and the otherwise nonpolar molecules containing these functional groups become polar and so become soluble in some [[Aqueous solution|aqueous]] environment.

Combining the names of functional groups with the names of the parent [[alkane]]s generates what is termed a [[systematic name|systematic nomenclature]] for naming [[organic compound]]s. In traditional nomenclature, the first carbon atom after the carbon that attaches to the functional group is called the [[alpha carbon]]; the second, beta carbon, the third, gamma carbon, etc. If there is another functional group at a carbon, it may be named with the Greek letter, e.g., the gamma-amine in [[gamma-aminobutyric acid]] is on the third carbon of the carbon chain attached to the carboxylic acid group. [[IUPAC nomenclature of organic chemistry|IUPAC convention]]s call for numeric labeling of the position, e.g. 4-aminobutanoic acid. In traditional names various qualifiers are used to label [[isomer]]s, for example, isopropanol (IUPAC name: propan-2-ol) is an isomer of n-propanol (propan-1-ol). The term [[Moiety (chemistry)|moiety]] has some overlap with the term "functional group". However, a moiety is an entire "half" of a molecule, which can be not only a single functional group, but also a larger unit consisting of multiple functional groups. For example, an "aryl moiety" may be any group containing an [[Aromaticity|aromatic ring]], regardless of how many functional groups the said aryl has.

==Table of common functional groups==
The following is a list of common functional groups.<ref>{{cite book |last= Brown |first= Theodore |title= Chemistry: the central science |publisher= Prentice Hall |location= Upper Saddle River, NJ |year= 2002 |isbn= 0130669970 |page=1001}}</ref> In the formulas, the symbols R and R' usually denote an attached hydrogen, or a [[hydrocarbon]] [[side chain]] of any length, but may sometimes refer to any group of atoms.

===Hydrocarbons===
Hydrocarbons are a class of molecule that is defined by functional groups called [[wikt:hydrocarbyl|hydrocarbyl]]s that contain only carbon and hydrogen, but vary in the number and order of double bonds. Each one differs in type (and scope) of reactivity.

{| class="wikitable" style="background: #ffffff; text-align: center;width:550px"
|-
! [[Chemical class]]
! Group
! Formula
! Structural Formula
! Prefix
! Suffix
! Example
|-
| [[Alkane]] ||[[Alkyl]]
| R(CH<sub>2</sub>)<sub>n</sub>H
| [[File:Alkyl-(general)-skeletal.svg|75px|Alkyl]]
| alkyl- || -ane
| [[File:Ethan Keilstrich.svg|135x135px]]<br>[[Ethane]]
|-
| [[Alkene]] || [[Alkene|Alkenyl]]
| R<sub>2</sub>C=CR<sub>2</sub>
| [[File:Alkene-2D-skeletal.svg|75px|Alkene]]
| alkenyl- || -ene
| [[File:Ethylene.svg|75px|ethylene]]<br>[[Ethylene]]<br>''(Ethene)''
|-
| [[Alkyne]] || [[Alkyne|Alkynyl]]
| RC≡CR'
| <chem>R-C#C-R'</chem>
| alkynyl- || -yne
| <chem>H-C#C-H</chem><br>[[Acetylene]]<br>''(Ethyne)''
|-
|-
| [[Benzene|Benzene derivative]]
| [[Phenyl]]
| RC<sub>6</sub>H<sub>5</sub><br>RPh
| [[File:Phenyl-group.svg|75px|Phenyl]]
| phenyl- || -benzene
| [[File:Cumene-skeletal.svg|75px]]<br>[[Cumene]]<br>''(Isopropylbenzene)''
|-
|}
There are also a large number of branched or ring alkanes that have specific names, e.g., [[tert-butyl]], [[bornyl]], [[cyclohexyl]], etc. There are several functional groups that contain an alkene such as [[vinyl group]], [[allyl group]], or [[Acryl|acrylic group]]. Hydrocarbons may form charged structures: positively charged [[carbocation]]s or negative [[carbanion]]s. Carbocations are often named ''-um''. Examples are [[tropylium]] and [[triphenylmethyl]] cations and the [[cyclopentadienyl]] anion.

===Groups containing halogen===
[[Haloalkane]]s are a class of molecule that is defined by a carbon–[[halogen]] bond. This bond can be relatively weak (in the case of an iodoalkane) or quite stable (as in the case of a fluoroalkane). In general, with the exception of [[fluorination|fluorinated]] compounds, haloalkanes readily undergo [[nucleophilic substitution]] reactions or [[elimination reaction]]s. The substitution on the carbon, the acidity of an adjacent proton, the solvent conditions, etc. all can influence the outcome of the reactivity.

{| class="wikitable" style="background: #ffffff; text-align: center;width:550px"
|-
! [[Chemical class]]
! Group
! Formula
! Structural formula
! Prefix
! Suffix
! Example
|-
| [[haloalkane]] || [[halogen|halo]]
| RX
| <chem>R-X</chem>
| halo- || alkyl '''halide'''
| [[File:Chloroethane-skeletal.svg|65x65px]]<br>[[Chloroethane]]<br>''(Ethyl chloride)''
|-
| [[fluoroalkane]] || [[fluorine|fluoro]]
| RF
| <chem>R-F</chem>
| fluoro- || alkyl '''fluoride'''
| [[File:Fluoromethane.svg|92x92px]]<br>[[Fluoromethane]]<br>''(Methyl fluoride)''
|-
| [[chloroalkane]] || [[chlorine|chloro]]
| RCl
| <chem>R-Cl</chem>
| chloro- || alkyl '''chloride'''
| [[File:Chloromethane.svg|98x98px|Chloromethane]]<br>[[Chloromethane]]<br>''(Methyl chloride)''
|-
| [[bromoalkane]] || [[bromine|bromo]]
| RBr
| <chem>R-Br</chem>
| bromo- || alkyl '''bromide'''
| [[File:Methyl bromide.svg|107x107px]]<br>[[Bromomethane]]<br>''(Methyl bromide)''
|-
| [[iodoalkane]] || [[iodine|iodo]]
| RI
| <chem>R-I</chem>
| iodo- || alkyl '''iodide'''
| [[File:Iodomethane.svg|75px|Iodomethane]]<br>[[Iodomethane]]<br>''(Methyl iodide)''
|-
|}

===Groups containing oxygen===
Compounds that contain C-O bonds each possess differing reactivity based upon the location and [[orbital hybridisation|hybridization]] of the C-O bond, owing to the electron-withdrawing effect of sp-hybridized oxygen (carbonyl groups) and the donating effects of sp<sup>2</sup>-hybridized oxygen (alcohol groups).
{| class="wikitable" style="background: #ffffff; text-align: center;width:300px"
|-
! [[Chemical class]]
! Group
! Formula
! Structural formula
! Prefix
! Suffix
! Example
|-
| [[Alcohol (chemistry)|Alcohol]]
 || [[Hydroxyl]]
| ROH
| [[File:Hydroxy-group-bw.svg|60px|center|Hydroxyl]]
| hydroxy- || '''-ol'''
| [[File:Methanol-2D.svg|90px|methanol]]<br>[[Methanol]]
|-
| [[Ketone]] || [[Ketone]]
| RCOR'
| [[File:Ketone-group-2D-skeletal.svg|Ketone|75px]]
| -oyl-&nbsp;(-COR')<br>or<br>oxo- (=O) || '''-one'''
| [[File:Butanone-skeletal-structure.svg|75px|Butanone]]<br>[[Butanone]]<br>''(Methyl ethyl ketone)''
|-
| [[Aldehyde]] || [[Aldehyde]]
| RCHO
| [[File:Skeletal formula of an aldehyde group.svg|75px|Aldehyde]]
| formyl- (-COH)<br>or<br>oxo- (=O)|| '''-al'''
| [[File:Acetaldehyde-skeletal.svg|75px|acetaldehyde]]<br>[[Acetaldehyde]]<br>''(Ethanal)''
|-
| [[Acyl halide]] || Haloformyl
| RCOX
| [[File:Acyl-halide-skeletal2D.svg|75px|Acyl halide]]
| carbonofluoridoyl-<br>carbonochloridoyl-<br>carbonobromidoyl-<br>carbonoiodidoyl- || -oyl '''fluoride'''<br> -oyl '''chloride'''<br> -oyl '''bromide'''<br> -oyl '''iodide'''
| [[File:Acetyl-chloride.svg|75px|Acetyl chloride]]<br>[[Acetyl chloride]]<br>''(Ethanoyl chloride)''
|-
|[[Carbonate ester|Carbonate]]
| [[Carbonate ester]]
| ROCOOR'
| [[File:Carbonate-group-skeletal.svg|75px|Carbonate]]
| (alkoxycarbonyl)oxy-
| alkyl '''carbonate'''
| [[File:Triphosgen Strukturformel.svg|90px|triphosgene]]<br>[[Triphosgene]]<br>''(bis(trichloromethyl) carbonate)''
|-
| [[Carboxylic acid|Carboxylate]]
| [[Carboxylate]] || RCOO<sup>−</sup>
| [[File:Carboxylate-resonance-hybrid.svg|60px|center|Carboxylate]]<br>[[File:Carboxylate-canonical-forms.svg|119x119px|Carboxylate]]

| carboxylato- || -oate
| [[File:Sodium-acetate-2D-skeletal.png|75px|Sodium acetate]]<br>[[Sodium acetate]]<br>''(Sodium ethanoate)''
|-
| [[Carboxylic acid]]
| [[Carboxyl]] || RCOOH
| [[File:Carboxylic-acid-skeletal.svg|75px|Carboxylic acid]]
| carboxy- || -oic '''acid'''
| [[File:Acetic-acid-2D-skeletal.svg|75px|Acetic acid]]<br>[[Acetic acid]]<br>''(Ethanoic acid)''
|-
| [[Ester]] || [[Ester|Carboalkoxy]]
| RCOOR'
| [[File:Ester-skeletal.svg|Ester|75px]]
| alkanoyloxy-<br>or<br>alkoxycarbonyl
| alkyl alkan'''oate'''
| [[File:Ethyl butyrate.png|75px|Ethyl butyrate]]<br>[[Ethyl butyrate]]<br>''(Ethyl butanoate)''
|-
| [[Organic peroxide|Hydroperoxide]]
| [[Organic peroxide|Hydroperoxy]]
| ROOH
| [[File:Hydroperoxide-group-2D.svg|75px|Hydroperoxy]]
| hydroperoxy-
| alkyl '''hydroperoxide'''
| [[File:TBHP.png|75px|''tert''-Butyl hydroperoxide]]<br>[[tert-Butyl hydroperoxide|''tert''-Butyl hydroperoxide]]
|-
| [[Organic peroxide|Peroxide]]
| [[Organic peroxide|Peroxy]]
| ROOR'
| [[File:Peroxy-group.svg|75px|Peroxy]]
| peroxy-
| alkyl '''peroxide'''
| [[File:Di-tert-butyl peroxide.svg|75px|Di-tert-butyl peroxide]]<br>[[Di-tert-butyl peroxide]]
|-
| [[Ether]] || [[Ether]]
| ROR'
| [[File:Ether-(general).svg|60px|center|Ether]]
| alkoxy-
| alkyl '''ether'''
| [[File:Diethyl ether chemical structure.svg|75px|Diethyl ether]]<br>[[Diethyl ether]]<br>''(Ethoxyethane)''
|-
| [[Hemiacetal]] || [[Hemiacetal]]
| R<sub>2</sub>CH(OR<sub>1</sub>)(OH)
| [[File:Hemiacetal general.svg|75px|Hemiacetal]]
| alkoxy -ol
| -al alkyl '''hemiacetal'''
|
|-
| [[Hemiketal]] || [[Hemiketal]]
| RC(ORʺ)(OH)R'
| [[File:Hemiketal-2D-skeletal.png|75px|Hemiketal]]
| alkoxy -ol
| -one alkyl '''hemiketal'''
|
|-
| [[Acetal]] || [[Acetal]]
| RCH(OR')(OR")
| [[File:Acetal-2D-skeletal.png|75px|Acetal]]
| dialkoxy-
| -al dialkyl '''acetal'''
|
|-
| [[Ketal]] (or [[Acetal]]) || [[Ketal]] (or [[Acetal]])
| {{nowrap|RC(OR")(OR‴)R'}}
| [[File:Ketal-2D-skeletal.png|75px|Ketal]]
| dialkoxy-
| -one dialkyl '''ketal'''
|
|-
| [[Orthoester]] || [[Orthoester]]
| {{nowrap|RC(OR')(OR")(OR‴)}}
| [[File:Orthoester general structure.svg|75px|Orthoester]]
| trialkoxy-
|
|
|-
| [[Heterocycle]]<br> (if cyclic) || [[Methylenedioxy]]
| {{nowrap|(–OCH<sub>2</sub>O–)}}
|
[[File:Methylenedioxy graphic (ChemDraw).png|50px|frameless]]
| methylenedioxy-
| -dioxole
| [[File:Benzo(d)(1,3)dioxole 200.svg|75px]]<br>[[1,3-Benzodioxole|1,2-Methylenedioxybenzene]]<br>''(1,3-Benzodioxole)''
|-
| [[Orthocarbonate ester]] || [[Orthocarbonate ester]]
| {{nowrap|C(OR)(OR')(OR")(OR‴)}}
| [[File:Orthocarbonate-ester.svg|75px|Orthocarbonate ester]]
| tetralkoxy-
| ''tetraalkyl'' '''orthocarbonate'''
| [[File:Tetramethylorthocarbonat.svg]]<br>[[Tetramethoxymethane]]
|-
| [[Organic acid anhydride]] || [[Carboxylic anhydride]]
| {{nowrap|R<sub>1</sub>(CO)O(CO)R<sub>2</sub>}}
| [[File:FunktionelleGruppen Carbonsäureanhydrid.svg|75px|Carboxylic anhydride]]
|
| anhydride
| [[File:Butyric anhydride.svg|75px|Butyric anhydride]]<br>[[Butyric anhydride]]
|}

===Groups containing nitrogen===
Compounds that contain nitrogen in this category may contain C-O bonds, such as in the case of [[amide]]s.
{| class="wikitable" style="background: #ffffff; text-align: center;width:700px"
|-
! [[Chemical class]]
! Group
! Formula
! Structural formula
! Prefix
! Suffix
! Example
|-
| [[Amide]] || [[Carboxamide]]
| RCONR'R"
| [[File:Amide-(tertiary)-skeletal.svg|85px|Amide]]
| carboxamido-<br>or<br>carbamoyl-|| -amide
| [[File:Acetamide skeletal.svg|75px|acetamide]]<br>[[Acetamide]]<br>''(Ethanamide)''
|-
|[[Amidine]]
|[[Amidine]]
|R<sub>4</sub>C(NR<sub>1</sub>)(NR<sub>2</sub>R<sub>3</sub>)
|[[File:Amidines.svg|frameless|132x132px]]
| amidino-
| -amidine
|[[File:Acetamidine-2D-skeletal.png|alt=|frameless|86x86px]]acetamidine
(acetimidamide)
|-
|[[Guanidine]]
|[[Guanidine]]
|RNC(NR<sub>2</sub>)<sub>2</sub>)
|[[File:Guanidine-group-2D-skeletal.svg|frameless|132x132px]]
| Guanidin-
| -Guanidine
|[[File:Guanidinopropionic acid.png|alt=|frameless|86x86px]]Guanidinopropionic acid
|-
| rowspan="5" | [[Amine]]s
| [[amine|Primary amine]]
| RNH<sub>2</sub>
| [[File:1°-amino-group.png|75px|Primary amine]]
| amino- || -amine
| [[File:Methylamine-2D.png|75px|methylamine]]<br>[[Methylamine]]<br>''(Methanamine)''
|-
| [[amine|Secondary amine]]
| R'R"NH
| [[File:Amine-(secondary).png|75px|Secondary amine]]
| amino- || -amine
| [[File:Dimethylamine-2D.png|75px|dimethylamine]]<br>[[Dimethylamine]]
|-
| [[amine|Tertiary amine]]
| R<sub>3</sub>N
| [[File:Amine-(tertiary).png|75px|Tertiary amine]]
| amino- || -amine
| [[File:Trimethylamine chemical structure.png|75px|trimethylamine]]<br>[[Trimethylamine]]
|-
| [[Quaternary ammonium cation|4° ammonium ion]]
| R<sub>4</sub>N<sup>+</sup>
| [[File:Quaternary-ammonium-cation.svg|75px|Quaternary ammonium cation]]
| ammonio- || -ammonium
| [[File:Choline-skeletal.svg|150px|Choline]]<br>[[Choline]]
|-
|[[Hydrazone]]
|R'R"CN<sub>2</sub>H<sub>2</sub>
|[[File:Hydrazone-2D.png|thumb|83x83px]]
|hydrazino-
| -hydrazine
|[[File:Benzophenone hydrazone-structure.png|thumb|129x129px|[[Benzophenone]]]]
|-
|rowspan="4" | [[Imine]]
| [[imine|Primary ketimine]]
| RC(=NH)R'
| [[File:Imine-(primary)-skeletal.svg|75px|Imine]]
| imino- || -imine
|
|-
| [[imine|Secondary ketimine]]
| <chem>RC(=NR'')R'</chem>
| [[File:Imine-(secondary)-skeletal.svg|75px|Imine]]
| imino- || -imine
|
|-
| [[imine|Primary aldimine]]
| RC(=NH)H
| [[File:Aldimine-(primary)-skeletal.svg|75px|Imine]]
| imino- || -imine
| [[File:Ethanimine skeletal.svg|75px|Ethanimine]]<br>[[Ethanimine]]
|-
| [[imine|Secondary aldimine]]
| RC(=NR')H
| [[File:Aldimine-(secondary)-skeletal.svg|75px|Imine]]
| imino- || -imine
|
|-
| [[Imide]] || [[Imide]]
| (RCO)<sub>2</sub>NR'
| [[File:Imide-group.svg|75px|Imide]]
| imido-
| -imide
| [[File:Succinimide.svg|75px|Succinimide]]<br>[[Succinimide]]<br>(Pyrrolidine-2,5-dione)
|-
| [[Azide]]
| [[Azide]]
| RN<sub>3</sub>
| [[File:Azide-2D.svg|75px|Organoazide]]
| azido- || alkyl '''azide'''
| [[File:Phenyl azide-chemical.png|75px|Phenyl azide]]<br>[[Phenyl azide]]<br>(Azidobenzene)
|-
| [[Azo compound]]
| [[Azo compound|Azo<br>(Diimide)]]
| RN<sub>2</sub>R'
| [[File:Azo-group.svg|75px|Azo.pngl]]
| azo- || -diazene
| [[File:Methyl-orange-skeletal.png|150px|Methyl orange]]<br>[[Methyl orange]]<br>(p-dimethylamino-azobenzenesulfonic acid)
|-
| rowspan=2|[[Cyanate]]s
| [[Cyanate]] || ROCN
| [[File:Cyanate-group.svg|75px|Cyanate]]
| cyanato-
| alkyl '''cyanate'''
|[[File:Methyl cyanate.svg|75px|Methyl cyanate]]<br>Methyl cyanate
|-
| [[Isocyanate]] || RNCO
| [[File:Isocyanate-group.svg|75px|Isocyanate]]
| isocyanato-
| alkyl '''isocyanate'''
| [[File:Methyl-isocyanate.svg|75px|Methyl isocyanate]]<br>[[Methyl isocyanate]]
|-
| [[Nitrate]] || [[Nitrate]]
| RONO<sub>2</sub>
| [[File:Nitrate-group-2D.svg|75px|Nitrate]]
| nitrooxy-, nitroxy- ||
alkyl '''nitrate'''
| [[File:Amyl nitrate.svg|150px|Amyl nitrate]]<br>[[Amyl nitrate]]<br>''(1-nitrooxypentane)''
|-
| rowspan=2|[[Nitrile]]
| [[Nitrile]]
| RCN
| <chem>R-\!#N</chem>
| cyano-
| alkane'''nitrile'''<br>alkyl '''cyanide'''
| [[File:Benzonitrile structure.png|75px|Benzonitrile]]<br>[[Benzonitrile]]<br>''(Phenyl cyanide)''
|-
| [[Isonitrile]] || RNC
| [[File:Isonitrile structural formula.svg|thumb| ]]
| isocyano-
| alkane'''isonitrile'''<br>alkyl&nbsp;'''isocyanide'''
| <math chem>\ce{H3C}{-}\overset{+}{\ce{N}}\ce{#C^-}</math><br>[[Methyl isocyanide]]
|-
|[[Alkyl nitrites|Nitrite]]||[[Alkyl nitrites|Nitrosooxy]]
| RONO
| [[File:Nitrite-group-2D.svg|75px|Nitrite]]
| nitrosooxy- ||
alkyl '''nitrite'''
| [[File:Amyl nitrite.svg|150px|Amyl nitrite]]<br>[[Isoamyl nitrite]]<br>''(3-methyl-1-nitrosooxybutane)''
|-
| [[Nitro compound]]
| [[Nitro functional group|Nitro]]
| RNO<sub>2</sub>
| [[File:Nitro-group.svg|75px|Nitro]]
| nitro- || &nbsp;
| [[File:Nitromethane2.png|75px|Nitromethane]]<br>[[Nitromethane]]
|-
| [[Nitroso|Nitroso compound]]
| [[Nitroso]] || RNO
| [[File:Nitroso-compound-2D.svg|75px|Nitroso]]
| nitroso- (Nitrosyl-) || &nbsp;
| [[File:Nitrosobenzene.png|75px|Nitrosobenzene]]<br>[[Nitrosobenzene]]
|-
| [[Oxime]]
| [[Oxime]] || RCH=NOH
| [[File:General structure of oximes.svg|125px|Oxime]]
| &nbsp; || [[Oxime]]
| [[File:acetoxime.svg|75px|Acetone oxime]]<br>[[Acetone oxime]]<br>''(2-Propanone oxime)''
|-
| [[Pyridine|Pyridine derivative]]
| [[Pyridine|Pyridyl]]
| RC<sub>5</sub>H<sub>4</sub>N
|
[[File:4-pyridyl.svg|75px|4-pyridyl group]]<br>
[[File:3-pyridyl.svg|75px|3-pyridyl group]]<br>
[[File:2-pyridyl.svg|75px|2-pyridyl group]]
|
4-pyridyl<br>(pyridin-4-yl)

3-pyridyl<br>(pyridin-3-yl)

2-pyridyl<br>(pyridin-2-yl)
| -pyridine
| [[File:Nicotine skeletal.svg|75px|Nicotine]]<br>[[Nicotine]]
|-
| [[Carbamate|Carbamate ester]]
| [[Carbamate]] || RO(C=O)NR<sub>2</sub>
| [[File:Carbamate-group-2D-skeletal.png|85px|Carbamate]]
| (-carbamoyl)oxy- || -carbamate
| [[File:Isopropyl (3-chlorophenyl)carbamate 200.svg|125px|Chlorpropham]]<br>[[Chlorpropham]]<br>''(Isopropyl (3-chlorophenyl)carbamate)''
|-
|}

===Groups containing sulfur===
Compounds that contain sulfur exhibit unique chemistry due to sulfur's ability to form more bonds than oxygen, its lighter analogue on the periodic table. Substitutive nomenclature (marked as prefix in table) is preferred over functional class nomenclature (marked as suffix in table) for sulfides, disulfides, sulfoxides and sulfones.
{| class="wikitable" style="background: #ffffff; text-align: center;width:800px"
|-
! [[Chemical class]]
! Group
! Formula
! Structural formula
! Prefix
! Suffix
! Example
|-
| [[Thiol]]
| [[Thiol|Sulfhydryl]]
| RSH
| [[File:Thiol-group.svg|75px|Sulfhydryl]]
| sulfanyl-<br>(-SH)
| -'''thiol'''
| [[File:Ethanethiol-skeletal.svg|75px|Ethanethiol]]<br>[[Ethanethiol]]
|-
| [[Sulfide (organic)|Sulfide]]<br>([[Thioether]])
| [[Sulfide (organic)|Sulfide]]
| RSR'
| [[File:Sulfide-group-2D.svg|75px|Sulfide group]]
| ''substituent''&nbsp;sulfanyl-<br>(-SR')
| di(''substituent'')&nbsp;'''sulfide'''
|<br>[[File:Dimethylsulfide.png|130px|Dimethyl sulfide]]<br><br>[[(Methylsulfanyl)methane]]&nbsp;(prefix)&nbsp;or<br>[[Dimethyl sulfide]] (suffix)
|-
| [[Disulfide bond|Disulfide]] || [[Disulfide]]
| RSSR'
| [[File:Disulfide general formula.svg|75px|Disulfide]]
| ''substituent''&nbsp;disulfanyl-<br>(-SSR')
| di(''substituent'')&nbsp;'''disulfide'''
|<br>[[File:Dimethyl disulfide.PNG|130px|Dimethyl disulfide]]<br><br>[[(Methyldisulfanyl)methane]]&nbsp;(prefix)&nbsp;or<br>[[Dimethyl disulfide]] (suffix)
|-
| [[Sulfoxide]]
| [[Sulfoxide|Sulfinyl]]
| RSOR'
| [[File:Sulfoxide-2D.svg|75px|Sulfinyl group]]
| -sulfinyl-<br>(-SOR')
| di(''substituent'')&nbsp;'''sulfoxide'''
| [[File:Dimethylsulfoxid.svg|130px|DMSO]]<br>[[(Methanesulfinyl)methane]]&nbsp;(prefix)&nbsp;or<br>[[Dimethyl sulfoxide]] (suffix)
|-
| [[Sulfone]]
| [[Sulfone|Sulfonyl]]
| RSO<sub>2</sub>R'
| [[File:Sulfone-2D.svg|75px|Sulfonyl group]]
| -sulfonyl-<br>(-SO<sub>2</sub>R')
| di(''substituent'')&nbsp;'''sulfone'''
| [[File:DMSO2.svg|75px|Dimethyl sulfone]]<br>[[(Methanesulfonyl)methane]]&nbsp;(prefix)&nbsp;or<br>[[Dimethyl sulfone]] (suffix)
|-
| [[Sulfinic&nbsp;acid]] || Sulfino
| RSO<sub>2</sub>H
| [[File:Sulfinic-acid-2D.svg|75px]]
| sulfino-<br>(-SO<sub>2</sub>H)
| -'''sulfinic&nbsp;acid'''
| [[File:Hypotaurine.svg|75px|Hypotaurine]]<br>[[2-Aminoethanesulfinic acid]]
|-
| [[Sulfonic&nbsp;acid]] || Sulfo
| RSO<sub>3</sub>H
| [[File:Sulfonic-acid.svg|75px|Sulfonyl group]]
| sulfo-<br>(-SO<sub>3</sub>H)
| -'''sulfonic&nbsp;acid'''
| [[File:Benzenesulfonic-acid-2D-skeletal.png|75px|Benzenesulfonic acid]]<br>[[Benzenesulfonic acid]]
|-
| [[Sulfonate&nbsp;ester]] || Sulfo
| RSO<sub>3</sub>R'
| [[File:Sulfonic-ester.svg|75px|Sulfonic ester]]
| (-sulfonyl)oxy-<br>or<br>alkoxysulfonyl-
| ''R''' ''R''-'''sulfonate'''
| [[File:StructureMeOTf.svg|75px|Methyl trifluoromethanesulfonate]]<br>[[Methyl trifluoromethanesulfonate]] or<br>Methoxysulfonyl trifluoromethane (prefix)
|-
| rowspan=2|[[Thiocyanate]]
| [[Thiocyanate]] || RSCN
| [[File:Thiocyanate-group.svg|75px|Thiocyanate]]
| thiocyanato-<br>(-SCN)
| ''substituent''&nbsp;'''thiocyanate'''
| [[File:Phenyl thiocyanate.svg|100px|Phenyl thiocyanate]]<br>[[Phenyl thiocyanate]]
|-
| [[Isothiocyanate]] || RNCS
| [[File:Isothiocyanate-group.svg|75px|Isothiocyanate]]
| isothiocyanato-<br>(-NCS)
| ''substituent''&nbsp;'''isothiocyanate'''
| [[File:Allyl-isothiocyanate-2D-skeletal.png|100px|Allyl isothiocyanate]]<br>[[Allyl isothiocyanate]]
|-
| [[Thioketone]]
| [[Carbonothioyl]]
| RCSR'
| [[File:Thioketone-skeletal.svg|60px|Thione]]
| -thioyl-<br>(-CSR')<br>or<br>sulfanylidene-<br>(=S)
| -'''thione'''
| [[File:Thiobenzophenone-2D-skeletal.png|75px|Diphenylmethanethione]]<br>[[Diphenylmethanethione]]<br>([[Thiobenzophenone]])
|-
| [[Thial]]
| [[Carbonothioyl]]
| RCSH
| [[File:Thial-skeletal.svg|60px|Thial]]
| methanethioyl-<br>(-CSH)<br>or<br>sulfanylidene-<br>(=S)
| -'''thial'''
|
|-
|rowspan=2| [[Thiocarboxylic acid]]
| Carbothioic ''S''-acid
| RC=OSH
| [[File:Thioic acid.svg|60px|center|Thioic S-acid]]
| mercaptocarbonyl-
| -'''thioic''' ''S''-'''acid'''
| [[File:Thiobenzoic acid.svg|75px|Thiobenzoic acid]]<br>[[Thiobenzoic acid]]<br>''(benzothioic ''S''-acid)''
|-
| Carbothioic ''O''-acid
| RC=SOH
| [[File:Thioic O-acid.svg|60px|center|Thioic O-acid]]
| hydroxy(thiocarbonyl)-
| -'''thioic''' ''O''-'''acid'''
|
|-
|rowspan=2| [[Thioester]]
| Thiolester
| RC=OSR'
| [[File:Thiolester-skeletal.svg|75px|Thiolester]]
|
| ''S''-alkyl-alkane-'''thioate'''
| [[File:S-methyl-thioacrylate-2D-skeletal.png|75px|S-methyl thioacrylate]]<br>[[S-methyl thioacrylate]]<br>''(''S''-methyl prop-2-enethioate)''
|-
| Thionoester
| RC=SOR'
| [[File:Thionoester-skeletal.svg|75px|Thionoester]]
|
| ''O''-alkyl-alkane-'''thioate'''
|
|-
| [[Thiocarboxylic acid#Dithiocarboxylic acids|Dithiocarboxylic acid]]
| Carbodithioic acid
| RCS<sub>2</sub>H
| [[File:Dithioic-acid-skeletal.svg|60px|center|Dithiocarboxylic acid]]
| dithiocarboxy-
| -'''dithioic acid'''
| [[File:PhCS2H.svg|75px|Dithiobenzoic acid]]<br>[[Dithiobenzoic acid]]<br>''(Benzenecarbodithioic acid)''
|-
| [[Dithiocarboxylic acid ester]]
| Carbodithio
| RC=SSR'
| [[File:Dithioic-acid-ester-skeletal.svg|75px|Dithioate]]
|
| -'''dithioate'''
|
|}

===Groups containing phosphorus===
Compounds that contain phosphorus exhibit unique chemistry due to the ability of phosphorus to form more bonds than nitrogen, its lighter analogue on the periodic table.
{| class="wikitable" style="background: #ffffff; text-align: center;width:800px"
|-
! [[Chemical class]]
! Group
! Formula
! Structural formula
! Prefix
! Suffix
! Example
|-
| [[Phosphine]]<br>([[Phosphane]]) || Phosphino
| R<sub>3</sub>P
| [[File:Phosphine-general.svg|75px|A tertiary phosphine]]
| phosphanyl- || -phosphane
| [[File:Methylpropylphosphane-skeletal.svg|75px|Methylpropylphosphane]]<br>Methylpropylphosphane
|-
| [[Phosphonic acid]]
| Phosphono
| <chem>RP(=O)(OH)2</chem>
| [[File:Phosphonic-acid.svg|75px|Phosphono group]]
| phosphono-
| ''substituent'' '''phosphonic acid'''
| [[File:Benzylphosphonic-acid-2D-skeletal.png|75px|Benzylphosphonic acid]]<br>Benzylphosphonic acid
|-
| rowspan=2| [[Phosphate]]
| rowspan=2| Phosphate
| rowspan=2| <chem>ROP(=O)(OH)2</chem>
| rowspan=2| [[File:Phosphate-group.svg|75px|Phosphate group]]
| rowspan=2| phosphonooxy-<br>or<br>''O''-phosphono-&nbsp;(phospho-)
| rowspan=2| ''substituent'' '''phosphate'''
| [[File:G3P-2D-skeletal.png|75px|Glyceraldehyde 3-phosphate]]<br>[[Glyceraldehyde 3-phosphate|Glyceraldehyde&nbsp;3-phosphate]] (suffix)
|-
| [[File:Phosphocholine.png|75px|Phosphocholine]]<br>''O''-Phosphonocholine&nbsp;(prefix)<br>([[Phosphocholine]])
|-
| rowspan=2|[[Phosphodiester bonds|Phosphodiester]]
| rowspan=2|[[Phosphate]]
| rowspan=2|HOPO(OR)<sub>2</sub>
| rowspan=2|[[File:Phosphodiester-group.svg|75px|Phosphodiester]]
| rowspan=2|<small>[(alkoxy)hydroxyphosphoryl]oxy-<br>or<br>''O''-[(alkoxy)hydroxyphosphoryl]-</small>
| rowspan=2|di(''substituent'') hydrogen&nbsp;'''phosphate'''<br>or<br>phosphoric&nbsp;acid di(''substituent'')&nbsp;'''ester'''
| [[DNA]]
|-
| <small>''O''‑[(2‑Guanidinoethoxy)hydroxyphosphoryl]‑{{Smallcaps|l}}‑serine</small>&nbsp;(prefix)<br>([[Lombricine]])
|}

===Groups containing boron===
Compounds containing boron exhibit unique chemistry due to their having partially filled octets and therefore acting as [[Lewis acid]]s.

{| class="wikitable"
|-
! [[Chemical class]] !! Group !! Formula !! Structural formula !! Prefix !! Suffix !! Example
|-
| [[Boronic acid]] || Borono || RB(OH)<sub>2</sub> || [[File:Boronic-acid-2D.svg|70px|center]] || Borono- || ''substituent''<br>'''boronic acid''' || {{center|[[File:Phenylboronic acid.png|70px|Phenylboronic acid]]<br>[[Phenylboronic acid]]}}
|-
| [[Boronic acid#Boronic esters (also named boronate esters)|Boronic ester]] || Boronate || RB(OR)<sub>2</sub> || [[File:Boronate-ester-2D.svg|75px|center]] || O-[bis(alkoxy)alkylboronyl]- || ''substituent''<br>'''boronic acid'''<br>di(''substituent'') '''ester''' ||
|-
| [[Borinic acid]] || Borino || R<sub>2</sub>BOH || [[File:Borinic-acid-2D.svg|70px|center]] || Hydroxyborino- || di(''substituent'')<br>'''borinic acid''' ||
|-
| [[Boronic acid#Borinic acids and esters|Borinic ester]] || Borinate || R<sub>2</sub>BOR || [[File:Borinate-ester-2D.svg|75px|center]] || O-[alkoxydialkylboronyl]- || di(''substituent'')<br>'''borinic acid'''<br>''substituent'' '''ester''' || {{center|[[File:2-APB.png|140px|2-Aminoethoxydiphenyl borate]]<br><small>Diphenylborinic acid 2-aminoethyl ester</small><br>([[2-Aminoethoxydiphenyl borate]])}}
|}

=== Groups containing metals ===
{| class="wikitable"
|+
!Chemical class
!Structural formula
!Prefix
!Suffix
!Example
|-
|[[Organolithium reagent|Alkyllithium]]
|RLi
| rowspan="4" |(tri/di)alkyl-
| -lithium
|[[File:Meli is.svg|71x71px]]
[[methyllithium]]
|-
|[[Grignard reagent|Alkylmagnesium halide]]
|RMgX (X=Cl, Br, I){{Ref label|halogen|note 1|note 1}}
| -magnesium halide
|[[File:Methylmagnesiumchloride.svg|97x97px]]
[[methylmagnesium chloride]]
|-
|Alkylaluminium
|Al<sub>2</sub>R<sub>6</sub>
| -aluminium
|[[File:Trimethylaluminium-from-xtal-3D-bs-17.png|109x109px]]
[[trimethylaluminium]]
|-
|[[Silyl ether]]
|R<sub>3</sub>SiOR
| -silyl ether
|[[File:Trimethylsilyl triflate.svg]]
[[Trimethylsilyl trifluoromethanesulfonate|trimethylsilyl triflate]]
|}
{{Note label|halogen|note 1|note 1}} [[Fluorine]] is too electronegative to be bonded to magnesium; it becomes an [[Salt (chemistry)|ionic salt]] instead.

===Names of radicals or moieties===
These names are used to refer to the moieties themselves or to radical species, and also to form the names of halides and substituents in larger molecules.

When the parent hydrocarbon is unsaturated, the suffix ("-yl", "-ylidene", or "-ylidyne") replaces "-ane" (e.g. "ethane" becomes "ethyl"); otherwise, the suffix replaces only the final "-e" (e.g. "[[ethyne]]" becomes "[[ethynyl]]").<ref name="qmul"/>

When used to refer to moieties, multiple single bonds differ from a single multiple bond. For example, a [[methylene bridge]] (methanediyl) has two single bonds, whereas a [[methylidene group]] (methylidene) has one double bond. Suffixes can be combined, as in methylidyne (triple bond) vs. methylylidene (single bond and double bond) vs. methanetriyl (three double bonds).

There are some retained names, such as [[methylene group|methylene]] for methanediyl, 1,x-[[phenylene]] for phenyl-1,x-diyl (where x is 2, 3, or 4),<ref>{{cite web|url=https://www.acdlabs.com/iupac/nomenclature/93/r93_271.htm|title=R-2. 5 Substituent Prefix Names Derived from Parent Hydrides|publisher=IUPAC|year=1993|access-date=2018-12-15|archive-date=2019-03-22|archive-url=https://web.archive.org/web/20190322061930/https://www.acdlabs.com/iupac/nomenclature/93/r93_271.htm|url-status=live}} section P-56.2.1</ref> [[carbyne]] for methylidyne, and [[trityl]] for triphenylmethyl.

{| class="wikitable"
|-
! [[Chemical class]] !! Group !! Formula !! Structural formula !! Prefix !! Suffix !! Example
|-
| Single bond || || R• || || Ylo-<ref>{{cite web|url=http://www.chem.qmul.ac.uk/iupac/ions/RC813.html|title=Revised Nomenclature for Radicals, Ions, Radical Ions and Related Species (IUPAC Recommendations 1993: RC-81.3. Multiple radical centers)|access-date=2014-12-02|archive-url=https://web.archive.org/web/20170611171918/http://www.chem.qmul.ac.uk/iupac/ions/RC813.html|archive-date=2017-06-11|url-status=dead}}</ref> || -yl || {{center|[[Methyl group]]<br>[[Methyl radical]]}}
|-
| Double bond || || R: || || ? || -ylidene || {{center|[[Methylidene]]}}
|-
| Triple bond || || R⫶ || || ? || -ylidyne || {{center|[[Methylidyne]]}}
|-
| Carboxylic [[acyl]] radical || Acyl || R−C(=O)• || || ? || -oyl || {{center|[[Acetyl]]}}
|}

==See also==
* [[:Category:Functional groups]]
* [[Group contribution method]]

==References==
{{Reflist|refs=
<ref name="qmul">{{cite web |url=http://www.chem.qmul.ac.uk/iupac/ions/RC811.html#p11|title=RC-81.1.1. Monovalent radical centers in saturated acyclic and monocyclic hydrocarbons, and the mononuclear EH4 parent hydrides of the carbon family |last=Moss |first=G. P. |author2=W.H. Powell |work=IUPAC Recommendations 1993 |publisher=Department of Chemistry, [[Queen Mary University of London]]|access-date=25 February 2015 |archive-url=https://web.archive.org/web/20150209155729/http://www.chem.qmul.ac.uk/iupac/ions/RC811.html|archive-date=9 February 2015}}</ref>
}}

==External links==
{{Commons|Functional groups}}
* [https://www.acdlabs.com/iupac/nomenclature/ IUPAC Blue Book (organic nomenclature)]
* {{cite web|url=http://www.iupac.org/reports/provisional/abstract04/RB-prs310804/TableVII-3.04.pdf|title=IUPAC ligand abbreviations|date=2 April 2004|publisher=[[IUPAC]]|access-date=25 February 2015 |archive-url= https://web.archive.org/web/20070927121055/http://www.iupac.org/reports/provisional/abstract04/RB-prs310804/TableVII-3.04.pdf |archive-date=27 September 2007}}
* [https://www.pearson.com/channels/organic-chemistry/learn/johnny/molecular-representations/functional-groups Functional group video]

{{Functional groups}}
{{Organic chemistry}}
{{Authority control}}

[[Category:Functional groups| ]]
[[Category:Organic chemistry]]