Английская Википедия:4,4'-Bipyridine

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Шаблон:Chembox

4,4′-Bipyridine (abbreviated to 4,4′-bipy or 4,4′-bpy) is an organic compound with the formula Шаблон:Chem2. 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

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

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]

Файл:Paraquat synthesis.svg

Reactions

The reducing agent is N,N'-bis(trimethylsilyl)-4,4'-bipyridinylidene is produced by reduction of 4,4'-bipyridine in the presence of trimethylsilyl chloride (Me = CH3):

Шаблон:Chem2

The silylated derivative, which is red, is used in salt-free reductions.[5]

4,4′-bipyridine forms a variety of coordination polymers.[6]

References

Шаблон:Reflist

  1. See:
  2. Anderson gave the empirical formula for 4,4′-bipyridine as C10H10N2. See:
    • (Anderson, 1868), p. 209.
    • (Fehling, 1890), p. 974 (γ-Dipyridyl).
  3. Шаблон:Cite journal 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.
  4. Шаблон:Cite web
  5. Шаблон:Cite journal
  6. Шаблон:Cite journal