2,2′-Bipyridine

2,2′-Bipyridine
Skeletal formula of 2,2′-bipyridine
Ball-and-stick model of the 2,2′-bipyridine molecule
Space-filling model of the 2,2′-bipyridine molecule
Names
Preferred IUPAC name
2,2′-Bipyridine
Other names
Bipyridyl
Dipyridyl
Bipy
Bpy
Dipy
Identifiers
3D model (JSmol)
113089
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.006.069 Edit this at Wikidata
EC Number
  • 206-674-4 923-456-0
3720 936807
RTECS number
  • DW1750000
UNII
  • InChI=1S/C10H8N2/c1-3-7-11-9(5-1)10-6-2-4-8-12-10/h1-8H checkY
    Key: ROFVEXUMMXZLPA-UHFFFAOYSA-N checkY
  • InChI=1/C10H8N2/c1-3-7-11-9(5-1)10-6-2-4-8-12-10/h1-8H
    Key: ROFVEXUMMXZLPA-UHFFFAOYAP
  • n1ccccc1-c2ccccn2
Properties
(C5H4N)2
Appearance Colorless solid
Melting point 70 to 73 °C (158 to 163 °F; 343 to 346 K)
Boiling point 273 °C (523 °F; 546 K)
Structure
0 D
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 toxic
GHS labelling:
GHS06: ToxicGHS07: Exclamation mark
Danger
H301, H302, H311, H312, H319, H412
P264, P270, P273, P280, P301+P310, P301+P312, P302+P352, P305+P351+P338, P312, P321, P322, P330, P337+P313, P361, P363, P405, P501
Lethal dose or concentration (LD, LC):
15-78 mg/kg (oral, rat); 20-140 mg/kg (oral, mouse)
Related compounds
Related compounds
 4,4′-Bipyridine
Pyridine
Phenanthroline
3-Pyridylnicotinamide
Terpyridine
Biphenyl
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

2,2′-Bipyridine (bipy or bpy, pronounced /ˈbɪpiː/) is an organic compound with the formula (C5H4N)2. This colorless solid is an important isomer of the bipyridine family. It is a bidentate chelating ligand, forming complexes with many transition metals. Ruthenium and platinum complexes of bipy exhibit intense luminescence.[1]

Preparation, structure, and general properties

2,2'-Bipyridine was first prepared by decarboxylation of divalent metal derivatives of pyridine-2-carboxylate:[2]

2C5H4NCOO− → (C5H4N)2 + 2CO2 + 2e−

It is prepared by the dehydrogenation of pyridine using Raney nickel:[3]

Submitted by W. H. F. Sasse1

2C5H5N → (C5H4N)2 + H2

Substituted 2,2'-bipyridines

Unsymmetrically substituted 2,2'-bipyridines can be prepared by cross coupling reaction of 2-pyridyl and substituted pyridyl reagents.[4]

Structure

Although bipyridine is often drawn with its nitrogen atoms in cis conformation, the lowest energy conformation both in solid state and in solution is in fact coplanar, with nitrogen atoms in trans position.[5] Monoprotonated bipyridine adopts a cis conformation.[6]

Reactions

2,2'-bipyridine produces multiple coordination complexes. It binds metals as a chelating ligand, forming a 5-membered chelate ring.

See also

References

  1. ^ Broomhead J. A.; Young C. G. (1990). "Tris(2,2″-Bipyridine)Ruthenium(II) Dichloride Hexahydrate". Inorganic Syntheses. Vol. 28. pp. 338–340. doi:10.1002/9780470132593.ch86. ISBN 978-0-470-13259-3.
  2. ^ Constable; Housecroft (2019). "The Early Years of 2,2'-Bipyridine—A Ligand in its Own Lifetime". Molecules. 24 (21): 3951. doi:10.3390/molecules24213951. PMC 6864536. PMID 31683694.
  3. ^ Sasse, W. H. F. (1966). "2,2′-Bipyridine". Organic Syntheses. 46: 5. doi:10.15227/orgsyn.046.0005.
  4. ^ Liu, Tiandong; Fraser, Cassandra L. (2012). "Discussion Addendum for: Synthesis of 4-, 5-, and 6-Methyl-2,2'-bipyridine by a Negishi Cross-Coupling Strategy: 5-Methyl-2,2'-bipyridine". Organic Syntheses. 89: 76. doi:10.15227/orgsyn.089.0076.
  5. ^ Merritt, L. L.; Schroeder, E. (1956). "The Crystal Structure of 2,2′-Bipyridine". Acta Crystallographica. 9 (10): 801–804. doi:10.1107/S0365110X56002175.
  6. ^ Göller, A.; Grummt, U.-W. (2000). "Torsional barriers in biphenyl, 2,2′-bipyridine and 2-phenylpyridine". Chemical Physics Letters. 321 (5–6): 399–405. Bibcode:2000CPL...321..399G. doi:10.1016/S0009-2614(00)00352-3.