Pyrrolines, also known under the name dihydropyrroles, are three different heterocyclic organic chemical compounds that differ in the position of the double bond. Pyrrolines are formally derived from the aromate pyrrole by hydrogenation. 1-Pyrroline is a cyclic imine, whereas 2-pyrroline and 3-pyrroline are cyclic amines.

1-Pyrroline	2-Pyrroline	3-Pyrroline

Notable examples of pyrrolines containing various substituents include:

• 2-Acetyl-1-pyrroline, an aroma compound with a white bread-like smell
• Thienamycin, a beta-lactam antibiotic
• MTSL, a chemical used for certain NMR experiments
• Pyrrolysine, an unusual proteinogenic amino acid
• 1-Pyrroline-5-carboxylic acid, a biosynthetic metabolite
• Porphyrin, consisting of two alternating pairs of pyrrol and pyrroline connected via methine (=CH-) bridges

N-substituted pyrrolines can be generated by ring-closing metathesis.^[1]

• Pyrrole, the aromatic analog with two double bonds
• Pyrrolidine, the fully saturated analog without double bonds