title: Mannich Bases as Enone Precursors for Water-Mediated Efficient Synthesis of 2,3,6-Trisubstituted Pyridines and 5,6,7,8-Tetrahydroquinolines.
abstract: A highly efficient, regioselective, and environmentally friendly method has been developed for water-mediated synthesis of 2,3,6-trisubstituted pyridines and 5,6,7,8-tetrahydroquinolines. The introduced method allows easy preparation of various polysubstituted pyridines and 5,6,7,8-tetrahydroquinolines via domino reaction of an enolizable ketone, ammonia and enones derived from different Mannich bases in mild reaction conditions. Montmorillonite K-10 promoted this one-pot three-component reaction and gave both new and known 2,3,6-trisubstituted pyridines and 5,6,7,8-tetrahydroquinolines in good yields. The reaction protocol provides a wide array of functionality in construction of polysubstituted pyridines and 5,6,7,8-tetrahydroquinolines from commercially available starting materials in easily applicable and environmentally friendly conditions.
authors.affiliation: Hacettepe University, Chemistry Department, 06800 Beytepe, Ankara Turkey.
authors.forename: Essam Hamied Ahmed
authors.initials: EH
authors.lastname: Hanashalshahaby
authors.affiliation: Hacettepe University, Chemistry Department, 06800 Beytepe, Ankara Turkey.
authors.forename: Canan
authors.initials: C
authors.lastname: Unaleroglu
mesh_terms: D000641:Ammonia / Q000737:chemistry; D001546:Bentonite; D002384:Catalysis; D055772:Green Chemistry Technology; D007659:Ketones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008352:Mannich Bases / Q000737:chemistry*; D011725:Pyridines / Q000138:chemical synthesis*; D011804:Quinolines / Q000138:chemical synthesis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014867:Water / Q000737:chemistry
chemical_list: D007659:Ketones; D008352:Mannich Bases; D011725:Pyridines; D011804:Quinolines; C503188:montmorillonite K-10; D014867:Water; D001546:Bentonite; D000641:Ammonia; C528846:5,6,7,8-tetrahydroquinoline
keywords: 2,3,6-trisubstituted pyridines; 5,6,7,8-tetrahydroquinolines; Mannich bases; pyridine synthesis in water