Chichibabin Reaction
Chichibabin Reaction
the interaction of nitrogen-containing heterocyclic compounds, mainly pyridine, quinoline, and isoquinoline, with sodium amide, NaNH2, that leads to the formation of α-amino derivatives. For example, α-aminopyridine is obtained from pyridine:
The Chichibabin reaction (or Chichibabin animation reaction) is usually carried out at boiling temperatures in an aromatic hydrocarbon or in dialkyl aniline or at room temperature in liquid ammonia. If there is an excess of NaNH2, the principal product is α,α’-diaminopyridine. If both α-positions are occupied in the ring, the amino group attacks the γ-position. The reaction, used in preparative organic chemistry, was discovered by A. E. Chichibabin in 1914.
Also known as the Chichibabin reaction is the condensation of aldehydes or ketones with ammonia, leading to the formation of substituted pyridines, for example,
This reaction (also called Chichibabin pyridine synthesis) is carried out in the gaseous phase at temperatures of 300°–350°C with various catalysts of the Al2O3 type or in an autoclave at temperatures of 200°–250°C in the presence of concentrated aqueous ammonia. The reaction was carefully investigated by A. E. Chichibabin beginning in 1905; isolated syntheses were carried out by A. Baeyer in 1870 and P. Waage in 1882.