|Jmol-3D images||Image 1|
|Molar mass||71.12 g mol−1|
|Appearance||Clear colorless liquid|
|Melting point||−63 °C; −81 °F; 210 K|
|Boiling point||87 °C; 189 °F; 360 K|
|Solubility in water||Miscible|
|Acidity (pKa)||11.27 (pKa of conjugate acid in water),
19.56 (pKa of conjugate acid in acetonitrile)
|Main hazards||highly flammable, harmful, corrosive, possible mutagen|
|Flash point||3 °C; 37 °F; 276 K|
|Autoignition temperature||345 °C; 653 °F; 618 K|
|Related Nitrogen heterocyclic compounds||Pyrrole (aromatic with two double bonds)
Pyrroline (one double bond)
Pyrrolizidine (two pentagonal rings)
| (what is: / ?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Pyrrolidine, also known as tetrahydropyrrole, is an organic compound with the molecular formula (CH2)4NH. It is a cyclic secondary amine, also classified as a saturated heterocycle. It is a colourless liquid that is miscible with water and most organic solvents. It has a characteristic odor that is ammoniacal, fishy, shellfish-like. Compared to acyclic secondary amines, it is about 10 times more basic.
Synthesis and occurrence
Pyrrolidine is produced industrially by treatment of 1,4-butanediol with ammonia over an oxide catalyst.
Pyrrolidine is found in the leaves of tobacco and carrot. The pyrrolidine ring structure is present in numerous natural alkaloids such as nicotine and hygrine. It is found in many pharmaceutical drugs such as procyclidine and bepridil. It also forms the basis for the racetam compounds (e.g. piracetam, aniracetam). The amino acids proline and hydroxyproline are, in a structural sense, derivatives of pyrrolidine.
Pyrrolidine is used as a building block in the synthesis of more complex compounds. In organic chemistry, pyrrolidine is used to activate ketones and aldehydes toward nucleophilic addition by formation of enamines:
- Hall, H. K. (1957). "Correlation of the Base Strengths of Amines". Journal of the American Chemical Society 79 (20): 5441. doi:10.1021/ja01577a030.
- Kaljurand, I.; Kütt, A.; Sooväli, L.; Rodima, T.; Mäemets, V.; Leito, I.; Koppel, I. A. (2005). "Extension of the Self-Consistent Spectrophotometric Basicity Scale in Acetonitrile to a Full Span of 28 pKa Units: Unification of Different Basicity Scales". The Journal of Organic Chemistry 70 (3): 1019–1028. doi:10.1021/jo048252w. PMID 15675863.
- Pyrrolidine, The Good Scents Company
- Karsten Eller, Erhard Henkes, Roland Rossbacher, Hartmut Höke "Amines, Aliphatic" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. doi:10.1002/14356007.a02_001
- R. B. Woodward, I. J. Pachter, and M. L. Scheinbaum (1974), "2,2-(Trimethylenedithio)cyclohexanone", Org. Synth. 54: 39; Coll. Vol. 6: 1014