4,4'-Bipyridine
| Names | |
|---|---|
| Preferred IUPAC name
4,4′-Bipyridine | |
| Identifiers | |
3D model (JSmol) |
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| 113176 | |
| ChEBI | |
| ChEMBL | |
| ChemSpider | |
| ECHA InfoCard | 100.008.216 Edit this at Wikidata |
| EC Number |
|
| 3759 | |
PubChem CID |
|
| UNII | |
CompTox Dashboard (EPA) |
|
| |
| Properties | |
| C10H8N2 | |
| Molar mass | 156.188g·mol−1 |
| Melting point | 114°C (237°F; 387K) |
| Boiling point | 305°C (581°F; 578K) |
| Structure | |
| 0D | |
| Related compounds | |
Related compounds |
2,2′-Bipyridine Pyridine 4-Pyridylnicotinamide Terpyridine Biphenyl |
Except where otherwise noted, data are given for materials in their standard state (at 25°C [77°F], 100kPa).
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4,4′-Bipyridine (abbreviated to 4,4′-bipy or 4,4′-bpy) is an organic compound with the formula (C5H4N)2. It is one of several isomers of bipyridine. It is a colorless solid that is soluble in organic solvents. is mainly used as a precursor to N,N′-dimethyl-4,4′-bipyridinium [(C5H4NCH3)2]2+, known as paraquat.
History
[edit ]4,4′-Bipyridine was first obtained in 1868 by the Scottish chemist Thomas Anderson via heating pyridine with sodium metal.[1] However, Anderson's empirical formula for 4,4′-bipyridine was incorrect.[2] The correct empirical formula, and the correct molecular structure, for 4,4′-bipyridine was provided in 1882 by the Austrian chemist Hugo Weidel and his student M. Russo.[3]
Uses
[edit ]4,4'-Bipyridine is an intermediate in the production of paraquat, a widely used herbicide. In this process, pyridine is oxidized to 4,4'-bipyridine in a coupling reaction, followed by dimethylation to form paraquat.[4] One possible interpretation of the synthesis is:
However, the Birch reduction is not performed in a distinct step from the oxidation, and the reaction may not involve complete reduction to the aminoalkane (sodium is used in excess, so the distinction cannot be deduced from stoichiometry). An alternative interpretation is an interrupted reduction: another pyridine molecule captures the Birch pyridinyl radical intermediate to give bypyridinyl, which oxygen then quenches.
Reactions
[edit ]The reducing agent N,N'-bis(trimethylsilyl)-4,4'-bipyridinylidene is produced by reduction of 4,4'-bipyridine in the presence of trimethylsilyl chloride (Me = CH3):
- NC5H4C5H4N + 2 Li + 2 Me3SiCl → Me3SiNC5H4C5H4NSiMe3 + 2 LiCl
The silylated derivative, which is red, is used in salt-free reductions.[5]
4,4′-bipyridine forms a variety of coordination polymers.[6]
References
[edit ]- ↑ See:
- Anderson, Thomas (1868). "On the products of the destructive distillation of animal substances. Part V." Transactions of the Royal Society of Edinburgh. 25: 205–216. doi:10.1017/S0080456800028167. S2CID 251577345. Anderson called 4,4′-bipyridine "Dipyridine".
- German translation: Anderson, Th. (1870). "Ueber die Producte der trockenen Destillation thierischer Materien. Fünfter Theil" [On the products of the dry distillation of animal materials. Fifth part.]. Annalen der Chemie und Pharmacie (in German). 154: 270–286. doi:10.1002/jlac.18701540303.
- See also: Fehling, Hermann Christian von, ed. (1890). Neues Handwörterbuch der Chemie [New Concise Dictionary of Chemistry] (in German). Vol. 5. Braunschweig, Germany: Friedrich Vieweg und Sohn. p. 974. See γ-Dipyridyl.
- ↑ Anderson gave the empirical formula for 4,4′-bipyridine as C10H10N2. See:
- (Anderson, 1868), p. 209.
- (Fehling, 1890), p. 974 (γ-Dipyridyl).
- ↑ Weidel, H.; Russo, M. (1882). "Studien über das Pyridin" [Studies of pyridine]. Monatshefte für Chemie (in German). 3: 850–885. doi:10.1007/BF01516855. S2CID 97065714. The empirical formula for 4,4′-bipyridine (γ-Dipyridyl) appears on p. 856; the molecular structure of 4,4′-bipyridine (γ-Dipyridyl) appears on p. 867.
- ↑ Paraquat and Diquat. IPCS (Report). INCHEM Environmental Health Criteria. Vol. 39. UN WHO. 1984. § 3.1.1. ISBN 92 4 154099 4.
{{cite report}}: Check|isbn=value: checksum (help) - ↑ Tsurugi, Hayato; Mashima, Kazushi (2019). "Salt-Free Reduction of Transition Metal Complexes by Bis(trimethylsilyl)cyclohexadiene, -dihydropyrazine, and -4,4′-bipyridinylidene Derivatives". Accounts of Chemical Research. 52 (3): 769–779. doi:10.1021/acs.accounts.8b00638. PMID 30794373. S2CID 73505603.
- ↑ Biradha, K.; Sarkar, M.; Rajput, L. (2006). "Crystal engineering of coordination polymers using 4,4′-bipyridine as a bond between transition metal atoms". Chemical Communications (40): 4169–79. doi:10.1039/B606184B. PMID 17031423.