Terpyridine

Structural formula
General
Surname	Terpyridine
other names	2,6-bis (2-pyridyl) pyridines 2.2 ': 6', 2 '' - terpyridine Terpy
Molecular formula	C 15 H 11 N 3
Brief description	white, odorless prisms yellow needles (as picrat)
External identifiers / databases
CAS number 1148-79-4 EC number 214-559-5 ECHA InfoCard 100.013.235 PubChem 70848 Wikidata Q408228
properties
Molar mass	233.37 g mol −1
Physical state	firmly
Melting point	89-92 ° C 210 ° C (picrate)
boiling point	370 ° C
solubility	bad in cold, better in warm water soluble in many organic solvents insoluble in petroleum ether
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 300-310-315-318-335 P: 261-264-280-302 + 350-305 + 351 + 338-310
Toxicological data	1.99 mg kg −1 ( LD 50 ,  rat ,  oral )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Terpyridine is a heterocyclic chemical compound with the empirical formula C ₁₅ H ₁₁ N ₃ . It consists of three pyridine rings , which are linked to one another in the 2-positions and 2,6-positions.

synthesis

Terpyridine was first obtained in 1932 by oxidative coupling of pyridine in the presence of iron (III) chloride at 340 ° C in an autoclave. The result is a product mixture of various pyridine derivatives , bipyridines and quaterpyridine , which also contains terpyridine. By reacting 2-bromopyridine with 2,6-dibromopyridine with copper in the sense of a Ullmann coupling , terpyridine can be produced with higher selectivity.

A number of newer synthetic routes are known, which are often based on palladium- catalyzed coupling reactions ( Hiyama coupling , Stille coupling , Negishi coupling )

properties

Terpyridine is a chelating ligand which forms complexes of the form [M (Terpy) ₂ ] ^{n +} with many transition metals .

As part of the safe disposal of radioactive waste , methods for separating ( partitioning ) the nuclear material into element groups are currently being investigated. This requires the separation of the chemically similar minor actinides and lanthanides . Terpyridine was the first ligand to achieve this separation, albeit with a moderate separation factor of 7. In the meantime, however, there are significantly more selective extractants for this purpose.

Individual evidence

1. ↑ ^{a b c d e f g h} G. T. Morgan, FH Burstall: Dehydrogenation of pyridine by anhydrous ferric chloride , in: J. Chem. Soc. 1932 , 20-30; doi : 10.1039 / JR9320000020 .
2. ↑ ^{a b c} data sheet terpyridine from AlfaAesar, accessed on April 17, 2010 ( PDF )(JavaScript required) .
3. ↑ ^{a b} data sheet 2,2 ′: 6 ′, 2 ′ ′ - terpyridines from Sigma-Aldrich , accessed on May 20, 2017 ( PDF ).
4. ^ FH Burstall: Researches on the polypyridyls , in: J. Chem. Soc. 1938 , 1662-1672; doi : 10.1039 / JR9380001662 .
5. ↑ ^{a b} Y. Yamamoto, T. Tanaka, M. Yagi, M. Inamoto, in: Heterocycles 1996 , 42 , 189-194.
6. ↑ F.-Q. Fang, GS Hanan, Rapid and Efficient Synthesis of Functionalized Bipyridines , in: Synlett 2003 , 6 , 852-854.
7. ^ C. Madic, MJ Hudson High Level Liquid Waste Partitioning by Means of Completely Incinerable Extractants. Final Report, European Commission Contract No. FI2W-CT91-0112, EUR 18038, 1999 .
8. ↑ C. Ekberg, A. Fermvik, T. Retegan, G. Skarnemark, MRS Foreman, MJ Hudson, S. Englund, M. Nilson, Radiochim. Acta 2008 , 96 , 225-233.
9. ↑ Z. Kolarik, U. Müllich, F. Gassner, in: Solvent Extr. Ion Exch. 1999 , 17 , 23-32.
10. ↑ S. Trumm, G. Lieser, MRSJ Foreman, PJ Panak, A. Geist, Th. Fanghänel , A TRLFS study on the complexation of Cm (III) and Eu (III) with 4-t-butyl-6,6- bis- (5,6-diethyl-1,2,4-triazin-3-yl) -2,2-bipyridine in a water / 2-propanol mixture , in: Dalton Trans. 2010 , 39 , 923-929; doi : 10.1039 / b919247f .