Pyrrolidine
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| Names | |||
|---|---|---|---|
| Preferred IUPAC name
Pyrrolidine | |||
| Other names
Azolidine Azacyclopentane Tetrahydropyrrole Prolamine | |||
| Identifiers | |||
| 3D model (JSmol) |
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| ChEBI | |||
| ChemSpider | |||
| ECHA InfoCard | 100.004.227 | ||
| PubChem CID |
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| RTECS number | UX9650000 | ||
| UNII | |||
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| Properties | |||
| C4H9N | |||
| Molar mass | 71.12 g·mol−1 | ||
| Appearance | Clear colorless liquid | ||
| Density | 0.866 g/cm3 | ||
| Melting point | −63 °C (−81 °F; 210 K) | ||
| Boiling point | 87 °C (189 °F; 360 K) | ||
| Miscible | |||
| Acidity (pKa) | 11.27 (pKa of conjugate acid in water),[1] 19.56 (pKa of conjugate acid in acetonitrile)[2] | ||
| -54.8·10−6 cm3/mol | |||
| Hazards | |||
| Main hazards | highly flammable, harmful, corrosive, possible mutagen | ||
| Safety data sheet | MSDS | ||
| R-phrases (outdated) | R11-R20/21/22-R34[3] | ||
| S-phrases (outdated) | S16-S26-S28-S36/37-S45 | ||
| NFPA 704 | |||
| Flash point | 3 °C (37 °F; 276 K) | ||
| 345 °C (653 °F; 618 K) | |||
| Related compounds | |||
| Related Nitrogen heterocyclic compounds |
Pyrrole (aromatic with two double bonds) Pyrroline (one double bond) Pyrrolizidine (two pentagonal rings) | ||
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |||
 verify (what is  ?) | |||
| Infobox references | |||
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 an ammonia-like, but characteristic odor.[4] In addition to pyrrolidine itself, many substituted pyrrolidines are known.
Synthesis and occurrence
Pyrrolidine is produced by treatment of 1,4-butanediol with ammonia over an oxide catalyst.[5]
Many modifications of pyrrolidine are found in natural and synthetic chemistry. The pyrrolidine ring structure is present in numerous natural alkaloids such as nicotine and hygrine. It is found in many 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.
Nicotine contains an N-methylpyrrolidine ring linked to a pyridine ring.
Reactions
Pyrrolidine is a base. Its basicity is typical of other dialkyl amines.[6] Relative to many secondary amines, pyrrolidine is distinctive because of its compactness, a consequence of its cyclic structure.
Pyrrolidine is used as a building block in the synthesis of more complex organic compounds. It is used to activate ketones and aldehydes toward nucleophilic addition by formation of enamines:[7]
References
- ↑ Hall, H. K. (1957). "Correlation of the Base Strengths of Amines". Journal of the American Chemical Society. 79 (20): 5441–5444. 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. PMID 15675863. doi:10.1021/jo048252w.
- ↑ MSDS
- ↑ John E. Amoore; L. Janet Forrester; Ron G. Buttery (1975). "Specific anosmia to 1-pyrroline: The spermous primary odor". Journal of Chemical Ecology. 1: 299–310. doi:10.1007/BF00988831.
- ↑ 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
- ↑ H. K. Hall, Jr. (1957). "Correlation of the Base Strengths of Amines". J. Am. Chem. Soc. 79: 5441. doi:10.1021/ja01577a030.
- ↑ R. B. Woodward, I. J. Pachter, and M. L. Scheinbaum (1974). "2,2-(Trimethylenedithio)cyclohexanone". Org. Synth. 54: 39.; Coll. Vol., 6, p. 1014