Title: Pyrrolidine
CAS Registry Number: 123-75-1
Additional Names: Tetrahydropyrrole
Molecular Formula: C4H9N
Molecular Weight: 71.12
Percent Composition: C 67.55%, H 12.76%, N 19.69%
Literature References: Found in tobacco and carrot leaves. Probable biosynthesis from ornithine and putrescine. Usually prepd by reduction of pyrrole.
Properties: Almost colorless liquid; unpleasant ammonia-like odor. Fumes in air. bp 88.5-89°. d422.5 0.8520. nD28 1.4402. Strong base. pK (25°) 2.89. Miscible with water. Soluble in alcohol, ether, chloroform.
Boiling point: bp 88.5-89°
pKa: pK (25°) 2.89
Index of refraction: nD28 1.4402
Density: d422.5 0.8520
Pyrrolnitrin Pyrrolysine Pyruvate Decarboxylase Pyruvic Acid Pyrvinium Pamoate

Pyrrolidine.png Pyrrolidine3d.png
CAS number 123-75-1 YesY
PubChem 31268
ChemSpider 29008 YesY
ChEBI CHEBI:33135 YesY
RTECS number UX9650000
Jmol-3D images Image 1
Molecular formula 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
Solubility in water Miscible
Acidity (pKa) 11.27 (pKa of conjugate acid in water),[1]

19.56 (pKa of conjugate acid in acetonitrile)[2]

R-phrases R11-R20/21/22-R34[3]
S-phrases S16-S26-S28-S36/37-S45
Main hazards highly flammable, harmful, corrosive, possible mutagen
NFPA 704
NFPA 704.svg
Flash point 3 °C; 37 °F; 276 K
Autoignition temperature 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)
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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 a characteristic odor that is ammoniacal, fishy, shellfish-like.[4] Compared to acyclic secondary amines, it is about 10 times more basic.