Functional group

From Free net encyclopedia

In organic chemistry functional groups are specific groups of atoms 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.

The following is a list of common functional groups. In the formulas, the symbols R and R' usually denotes an attached hydrogen, or a hydrocarbon chain of any length, but may sometimes refer to any group of atoms. Below is an image of multiple functional groups found in organic chemistry.

Chemical class Group Formula Graphical Formula Prefix Suffix
Alcohol Hydroxyl ROH Image:Alcohol-(general)-skeletal.png hydroxy- -ol
Aldehyde Aldehyde RCHO Image:Aldehyde-skeletal.png oxo- -al
Alkane Alkyl RH Image:Alkyl-(general)-skeletal.png alkyl- -ane
Alkene Alkenyl R2C=CR2 Image:Alkene-(general)-skeletal.png alkenyl- -ene
Alkyne Alkynyl RC≡CR' Image:Alkyne-(general)-skeletal.png alkynyl- -yne
Amide Carboxamide RCONR2 Image:Amide-(tertiary)-skeletal.png carboxamido- -amide
Amines Primary amine RNH2 Image:Amine-(primary).png amino- -amine
Secondary amine RNHR' Image:Amine-(secondary).png amino- -amine
Tertiary amine RNR'2 Image:Amine-(tertiary).png amino- -amine
Azo compound Azo RN2R' Image:Azo-group.png   alkyl(alkyl)diazene
Toluene derivative Benzyl

RCH2C6H5
RBn

Image:Benzyl-group.png benzyl-  
Carboxlate Carboxylate RCOO Image:Carboxylate-resonance-hybrid.png

Image:Carboxylate-canonical-forms.png

carboxy- -oate
Carboxylic acid Carboxyl RCOOH Image:Carboxylic-acid-skeletal.png carboxy- -oic acid
Cyanates Cyanate ROCN Image:Cyanate-group.png isocyanato- alkyl cyanate
Thiocyanate RSCN Image:Thiocyanate-group.png isothiocyanato- alkyl thiocyanate
Ether Ether ROR' Image:Ether-(general).png alkoxy- alkyl alkyl ether
Ester Ester RCOOR' Image:Ester-skeletal.png -oate
Haloalkane Halo RX Image:Halide-group.png halo- alkyl halide
Imine Primary ketimine RC(=NH)R' Image:Imine-(primary)-skeletal.png imino- -imine
Secondary ketimine RC(=NR)R' Image:Imine-(secondary)-skeletal.png imino- -imine
Primary aldimine RC(=NH)H Image:Aldimine-(primary)-skeletal.png imino- -imine
Secondary aldimine RC(=NR')H Image:Aldimine-(secondary)-skeletal.png imino- -imine
Isocyanide Isocyanide RNC Image:Isocyanide.png isocyano- alkyl isocyanide
Isocyanates Isocyanate RNCO Image:Isocyanate-group.png isocyanato- alkyl isocyanate
Isothiocyanate RNCS Image:Isothiocyanate-group.png isothiocyanato- alkyl isothiocyanate
Ketone Ketone RCOR' Image:Ketone-skeletal.png keto-, oxo- -one
Nitrile Nitrile RCN Image:Nitrile-(general)-skeletal.png cyano-

alkanenitrile
alkyl cyanide

Nitro compound Nitro RNO2 Image:Nitro-group.png nitro-  
Nitroso compound Nitroso RNO Image:Nitroso-group.png nitroso-  
Peroxide Peroxy ROOR Image:Peroxy-group.png peroxy- alkyl peroxide
Benzene derivative Phenyl RC6H5 Image:Phenyl-group.png phenyl- -benzene
Phosphoric acid ester Phosphodiester HOPO(OR)2 Image:Phosphodiester-group.png    
Pyridine derivative Pyridyl RC5H4N

Image:4-pyridyl.png
Image:3-pyridyl.png
Image:2-pyridyl.png

4-pyridyl / pyridin-4-yl
3-pyridyl / pyridin-3-yl
2-pyridyl / pyridin-2-yl

-pyridine
Sulfone Sulfonyl RSO2R' Image:Sulfone.png sulfonyl- alkyl alkyl sulfone
Sulfonic acid Sulfonic acid RSO3H Image:Sulfonic-acid.png sulfonyl- alkyl sulfonic acid
Sulfoxide Sulfinyl RSOR' Image:Sulfoxide.png sulfinyl- alkyl alkyl sulfoxide
Thiol Sulfhydryl RSH Image:Thiol-group.png mercapto-, sulfanyl- -thiol

Combining the names of functional groups with the names of the parent alkanes generates a powerful systematic nomenclature for naming organic compounds.

The non-hydrogen atoms of functional groups are always associated with each other and with the rest of the molecule by covalent bonds. When the group of atoms is associated with the rest of the molecule primarily by ionic forces, the group is referred to more properly as a polyatomic ion or complex ion. And all of these are called radicals, by a meaning of the term radical that predates the free radical.

The first carbon after the carbon that attaches to the functional group is called the alpha carbon.

External links

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