Friedländer synthesis

Mechanism

Two viable reaction mechanisms exist for this reaction. In the first mechanism 2-amino substituted carbonyl compound 1 and carbonyl compound 2 react in a rate-limiting step to aldol adduct 3. This intermediate loses water in an elimination reaction to unsaturated carbonyl compound 4 and then loses water again in imine formation to quinoline 7. In the second mechanism the first step is Schiff base formation to 5 followed by Aldol reaction to 6 and elimination to 7.

:[[Image:FriedlanderReactionMechanism.svg|Friedländer synthesis reaction mechanism]] The Pfitzinger reaction and the Niementowski quinoline synthesis are variations of the Friedländer reaction.

References

References

1. [[Organic Syntheses]], Coll. Vol. 3, p.　56 (1955); Vol. 28, p.　11 (1948). ([http://www.orgsyn.org/orgsyn/prep.asp?prep=cv3p0056 Article])
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3. (1883). "Ueber eine Darstellungsmethode im Pyridinkern substituirter Chinolinderivate". [[Chemische Berichte.
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9. Bergstrom, F. W.. (1944). "Heterocyclic Nitrogen Compounds. Part IIA. Hexacyclic Compounds: Pyridine, Quinoline, and Isoquinoline". [[Chem. Rev.]].
10. (2004). "Organic Reactions".
11. (2009). "Recent Advances in the Friedlander Reaction". Chemical Reviews.