Terpyridine

Terpyridine

Names
IUPAC name 2,6-bis(2-pyridyl)pyridine
Other names tripyridyl
Identifiers
CAS Number	1148-79-4 Y
3D model (Jmol)	Interactive image
ChEBI	CHEBI:245199 Y
ChEMBL	ChEMBL89445 Y
ChemSpider	64012 Y
ECHA InfoCard	100.013.235
PubChem	70848
InChI InChI=1S/C15H11N3/c1-3-10-16-12(6-1)14-8-5-9-15(18-14)13-7-2-4-11-17-13/h1-11H Y Key: DRGAZIDRYFYHIJ-UHFFFAOYSA-N Y InChI=1/C15H11N3/c1-3-10-16-12(6-1)14-8-5-9-15(18-14)13-7-2-4-11-17-13/h1-11H Key: DRGAZIDRYFYHIJ-UHFFFAOYAP
SMILES c1ccnc(c1)c2cccc(n2)c3ccccn3
Properties
Chemical formula	C15H11N3
Molar mass	233.27 g·mol−1
Appearance	white solid
Melting point	88 °C (190 °F; 361 K)
Boiling point	370 °C (698 °F; 643 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Terpyridine (2,2';6',2"-terpyridine, often abbreviated to Terpy or Tpy) is a heterocyclic compound derived from pyridine. It is a white solid that is soluble in most organic solvents. The compound is mainly used as a ligand in coordination chemistry.

Terpyridine was first synthesized by G. Morgan and F. H. Burstall in 1932 by the oxidative coupling of pyridines. This method, however, proceeded in low yields. More efficient syntheses have since been described, mainly starting from 2-acetylpyridine. One method produces an enaminone by the reaction of 2-acetylpyridine with N,N-dimethylformamide dimethyl acetal. The base-catalyzed reaction of 2-acetylpyridine with carbon disulfide followed by alkylation with methyl iodide gives C₅H₄NCOCH=C(SMe)₂. Condensation of this species with 2-acetylpyridine forms the related 1,5-diketone, which condenses with ammonium acetate to form a terpyridine. Treatment of this derivative with Raney nickel remove the thioether group.

Other methods have been developed for the synthesis of terpyridine and its substituted derivatives. Substituted terpyridines are also synthesized from palladium-catalyzed cross-coupling reactions. It can be prepared from bis-triazinyl pyridine.

Terpyridine is a tridentate ligand that binds metals at three meridional sites giving two adjacent 5-membered MN₂C₂ chelate rings. Terpyridine forms complexes with most transition metal ion as do other polypyridine compounds, such as 2,2'-bipyridine and 1,10-phenanthroline. Complexes containing two terpyridine complexes, i.e. [M(Terpy)₂]ⁿ⁺ are common. They differ structurally from the related [M(Bipy)₃]ⁿ⁺ complexes in being achiral.