De Novo Synthesis of 1,4-Dihydropyridines and Pyridines

Abstract

An efficient and general method for the synthesis of 1,4-dihydropyridines and pyridines based on a lithiation/isomerization/intramolecular carbolithiation sequence is reported. This procedure provides an efficient, divergent, and straightforward entry to a wide range of polysubstituted dihydropyridines and pyridines starting from readily available N-allyl-ynamides.

Green synthesis of polyhydroquinolines via MCR using Fe3O4/SiO2-OSO3H nanostructure catalyst and prediction of their pharmacological and biological activities by PASS

“…The isolated yields were 97, 95, 94, 92, 91 and 90% for the fresh catalyst and five subsequent recycled runs, respectively. As a result, the catalytic performance and recyclability of Fe 3 O 4 /SiO 2 -OSO 3 H were better than catalysts previously reported in the literature [8][9][10][11][12] and also our earlier works [13,20].…”

“…Therefore, several synthetic methods have been reported in the literature for their synthesis [8][9][10][11][12][13]. Although these various methods have some advantages for the synthesis of polyhydroquinolines, they have some drawbacks such as harsh reaction conditions, use of expensive catalysts or reagents, tedious workup procedures, sensitivity to water and toxicity.…”

Domino Reaction Sequence for the Synthesis of [2.2.2]Diazabicycloalkenes and Base-Promoted Cycloreversion to 2-Pyridone Alkaloids

“…1 Pyridines are one of the most prevalent aromatic heterocycles found in bioactive molecules and functional materials. 2 Cascade pericyclic processes 3 such as merged cycloaddition/ cycloreversion strategies, 4 particularly those employing 1,2,3- and 1,2,4-triazines, 5 are a valuable synthetic complement to traditional and more contemporary 6 condensation methods. 7 In comparison, merged cycloaddition/cycloreversion approaches for the direct synthesis of 2-pyridones are not common; 8 however, Hoornaert and co-workers validated the possibility of this approach using cycloaddition of chlorinated pyrazinone intermediates.…”

Intramolecular carbolithiation of N-allyl-ynamides: an efficient entry to 1,4-dihydropyridines and pyridines – application to a formal synthesis of sarizotan

“…While there were no examples of such exclusive anionic 6-endo-dig cyclizations reported to the best of our knowledge [39], we felt that the presence of the chelating group on the nitrogen may allow such a selective process and a clean formation of the (dihydro)pyridine ring system. We have indeed demonstrated the efficiency of this strategy [40] and now report in this manuscript a full account on this work as well as the application of our pyridine synthesis to a formal synthesis of the anti-dyskinesia agent sarizotan.…”