Categories: Synthesis of N-Heterocycles >
Synthesis of 2-pyridones
Recent Literature
A mild Cu-catalyzed approach for the N-arylation of 2-pyridones with
diaryliodonium salts proceeds readily at room temperature to provide N-arylpyridine-2-ones
in very good yields.
S.-H. Jung, D.-B. Sung, C.-H. Park, W.-S. Kim, J. Org. Chem.,
2016, 81, 7717-7724.
CuI-catalyzed coupling reactions of tetrabutylammonium pyridin-2-olates with
aryl iodides allow an efficient synthesis of N-aryl pyridine-2-ones. This
coupling reaction is mild, high-yielding, remarkably chemoselective (N- vs.
O-arylation), and tolerates labile functional groups.
H. Zhang, B.-C. Chen, B. Wang, S. T. Chao, R. Zhao, N. Lim, B. Balasubramanian, Synthesis, 2008,
1523-1524.
Vinylogous Blaise Reaction: Conceptually New Synthesis of Pyridin-2-ones
H. S. P. Rao, N. Muthanna, A. H. Padder,
Synlett, 2018, 29, 1649-1653.
A Co(III)-catalyzed redox-neutral annulation of benzamides and acrylamides
with vinylene carbonate provides isoquinolinones and pyridinones in very good
yields. This protocol tolerates diverse functional groups and substitution
patterns.
X. Li, T. Huang, Y. Song, Y. Qi, L. Li, Y. Li, Q. Xiao, Y. Zhang,
Org. Lett., 2020, 22, 5925-5930.
Formation of N-alkenyl alkynylamides by N-acylation of imines with
alkynoyl chlorides and the subsequent cationic Au(I)/PPh3-catalyzed
cycloisomerization allows a convergent and rapid assembly of substituted
2-pyridones.
H. Imase, K. Noguchi, M. Hirano, K. Tanaka, Org. Lett.,
2008,
10, 3563-3566.
The chemo- and regioselective reaction of the Blaise intermediate, generated in
situ from Reformatsky reagent and nitrile, with propiolates affords 2-pyridone
derivatives in good to excellent yields.
Y. S. Chun, K. Y. Ryu, Y. O. Ko, J. Y. Hong, J. Hong, H. Shin, S.-g. Lee, J. Org. Chem., 2009,
74, 7556-7558.
Enamine formation of substituted keto-dioxinones followed by thermolysis and
cyclization-aromatization enables the synthesis of various
6-substituted-4-hydroxy-2-pyridinones in good yields. The functionalized
keto-dioxinones were constructed via a diethylzinc mediated crossed Claisen
condensation reaction.
B. H. Patel, A. M. Mason, A. G. M. Barrett, Org. Lett., 2011,
13, 5156-5159.
A tandem condensation of propiolamide and cyclic β-keto methyl esters in water,
followed by acid- or base-promoted intramolecular ring closure and
decarboxylation enables an efficient synthesis of a 5,6-fused 2-pyridone
ring system.
A. B. Smith, III, O. Atasoylu, D. C. Beshore, Synlett, 2009,
2643-2646.
Related
Trapping of in situ generated active intermediate 1,4-oxazepines, formed from
base-promoted 7-exo-dig cyclization reaction of N-propargyl
enaminones, with alcohols/thiols and aldehydes provides
2-alkoxy/2-sulfenylpyridines and dihydrofuro[2,3-b]pyridines in good
yields within 30 min at room temperature. This cascade reaction generates 1
equiv of H2O as the sole byproduct.
G. Cheng, L. Xue, Y. Weng, X. Cui, J. Org. Chem.,
2017, 82, 9515-9524.