Preferred Label : chelation;
IUPAC definition : The formation or presence of bonds (or other attractive interactions) between two
or more separate binding sites within the same ligand and a single central atom. A
molecular entity in which there is chelation (and the corresponding chemical species
) is called a 'chelate'. The terms bidentate (or didentate), tridentate, tetradentate,
... multidentate are used to indicate the number of potential binding sites of the
ligand, at least two of which must be used by the ligand in forming a 'chelate'. For
example, the bidentate ethylenediamine forms a chelate with CuI in which both nitrogen
atoms of ethylenediamine are bonded to copper. (The use of the term is often restricted
to metallic central atoms.) The phrase 'separate binding sites' is intended to exclude
cases such as [PtCl sub 3 /sub (CH sub 2 /sub CH sub 2 /sub )] sup class minus
/sup , ferrocene and (benzene)tricarbonylchromium in which ethene, the cyclopentadienyl
group and benzene, respectively, are considered to present single binding sites to
the respective metal atom, and which are not normally thought of as chelates.;
Origin ID : C01012;
Automatic exact mappings (from CISMeF team)
- See also
The formation or presence of bonds (or other attractive interactions) between two
or more separate binding sites within the same ligand and a single central atom. A
molecular entity in which there is chelation (and the corresponding chemical species
) is called a 'chelate'. The terms bidentate (or didentate), tridentate, tetradentate,
... multidentate are used to indicate the number of potential binding sites of the
ligand, at least two of which must be used by the ligand in forming a 'chelate'. For
example, the bidentate ethylenediamine forms a chelate with CuI in which both nitrogen
atoms of ethylenediamine are bonded to copper. (The use of the term is often restricted
to metallic central atoms.) The phrase 'separate binding sites' is intended to exclude
cases such as [PtCl sub 3 /sub (CH sub 2 /sub CH sub 2 /sub )] sup class minus
/sup , ferrocene and (benzene)tricarbonylchromium in which ethene, the cyclopentadienyl
group and benzene, respectively, are considered to present single binding sites to
the respective metal atom, and which are not normally thought of as chelates.
