Categories: Synthesis of N-Heterocycles > benzo-fused N-Heterocycles >
Synthesis of quinoxalinones
Recent Literature
Benzimidazoles and quinoxalin-2(1H)-ones were synthesized by treatment of
2-(N-Boc-amino)phenylisocyanide with carboxylic acids and glyoxylic
acids, respectively via two-component coupling, deprotection, and intermolecular
cyclization.
Z.-Z. Chen, Y. Tang, L. Zuo, D.-Y. Tang, J. Zhang, Z.-G. Xu,
Synlett, 2014, 25, 2518-2520.
Efficient reactions of α-keto acids with 2-aminobenzamides,
2-aminobenzenethiols, benzene-1,2-diamines, and 2-aminophenols provide
quinazolinones, benzothiazoles, quinoxalinones, and benzoxazinones under
catalyst-free conditions, using water as the solvent. Products can be easily
purified through filtration and washing with ethanol (or crystallized).
J. Huang, W. Chen, J. Liang, Q. Yan, Y. Fan, M.-W. Chen, Y. Peng, J. Org. Chem., 2021, 86,
14866-14882.
Excited-state palladium-catalyzed alkylative cyclizations of acrylamides and
alkylations of quinoxalinones exhibit wide scope, occur under mild conditions,
and furnish products in excellent yields. Various primary, secondary, and
tertiary unactivated alkyl halides can serve as alkyl radical precursors.
G. C. Upreti, T. Singh, K. Khanna, A. Singh, J. Org. Chem., 2023, 88,
4422-4433.
Decarboxylative coupling reactions are synthetically appealing due to the
structural diversity, lack of toxicity, and widespread commercial accessibility
of carboxylic acids. A mild direct electron transfer between alkyl carboxylic
acids and excited-state substrates enables a C-H alkylation of quinoxalin-2(1H)-ones
without the involvement of any catalyst or additive.
K. Niu, H. Jiao, P. Zhou, Q. Wang, Org. Lett., 2023, 25,
8970-8974.
Photoredox catalysis enables a direct alkylation of a range of quinoxalinones
with alkylborates to provide a variety of 3-alkyl quinoxalinones in very good
yields. The practicality of this protocol was demonstrated by the concise
synthesis of a potential bioactive nonpeptide angiotensin II receptor antagonist.
W. Zhao, Y. Zhang, S. Yuan, X. Yu, L. Liu, J. Li, J. Org. Chem., 2023, 88,
6218-6226.
The combination of organophotoredox catalysis with hydrogen atom transfer
enables a mild C-H alkylation of quinoxalin-2(1H)-ones with feedstock
aldehydes, amides, alcohols, ethers, or cycloalkanes. This reaction occurred
under environmentally benign and external oxidant-free reaction conditions with
good functional group compatibility.
L. Wang, Z. Chen, G. Fan, X. Liu, P. Liu, J. Org. Chem., 2022, 87,
14580-14587.
The semi-heterogeneous g-C3N4/NaI dual system catalyzes a
C-C bond formation between quinoxalin-2(1H)-ones and arylhydrazines under
blue light irradiation to provide a wide range of 3-arylquinoxaline-2(1H)-ones
in high yields with excellent functional group tolerance.
H.-Y. Song, M.-Y. Liu, J. Huang, D. Wang, J. Jiang, J.-Y. Chen, T.-B. Yang,
W.-M. He, Green Chem., 2023, 25,
3292-3296.
A photoredox-catalyzed direct arylation of
quinoxalin-2-(1H)-ones using diaryliodonium triflates as convenient,
stable, and cheap aryl sources provides efficient access to a wide variety of
pharmaceutically important 3-arylquinoxalin-2-(1H)-ones. This operationally simple
method offers mild conditions, broad scope, scalability, and high functional
group tolerance.
R. K. Samanta, P. Meher, S. Murarka, J. Org. Chem., 2022, 87,
10947-10957.
The combination of tert-butyl hypochlorite, tetrabutylammonium iodide and
tetrabutylammonium chloride as oxidation system enables the transformation of
ethyl 2-(N-arylcarbamoyl)-2-iminoacetates into the corresponding quinoxalinones
in high yield. Oxygen exhibits a beneficial effect on the reaction.
D. Li, Y. Li, W. Yu, Synthesis, 2017,
49, 4283-4291.
Whereas the cyclocondensation of 2-aminothiophenols with 1,2-biselectrophiles
such as ethyl glyoxalate and diethyl oxalate in aqueous medium leads to the
formation of benzothiazole-2-carboxylates via a 5-endo-trig process
contrary to Baldwin’s rule, the reaction of 2-aminophenols/anilines produced the
corresponding benzazine-3-ones or benzazine-2,3-diones via a 6-exo-trig
process in compliance with Baldwin’s rule.
T. M. Dhameliya, S. S. Chourasiya, E. Mishra, P. S. Hadhavar, P. V. Bharatam, A.
K. Chakraborti, J. Org. Chem.,
2017, 82, 10077-10091.
Complexes of pyridyl glycosyl triazoles with Cu(I) salts were explored as
efficient catalysts to successfully assemble 2-amino-3-substituted and
3-substituted quinazolinones by domino/tandem cross-coupling reactions of
various N-substituted o-halobenzamides with cyanamide and
formamide, respectively.
S. K. Singh, S. Kumar, M. S. Yadav, V. K. Tiwari, J. Org. Chem., 2022, 87,
15389-15402.
An efficient, photoredox-catalyst-free radical alkylation of quinoxalin-2(1H)-ones
with photoexcited 4-alkyl-1,4-dihydropyridines (R-DHPs) as alkyl radical
precursors and acetoxybenziodoxole (BI-OAc) as an electron acceptor offers
benign reaction conditions and good functional group compatibility.
X.-K. He, J. Lu, A.-J. Zhang, Q.-Q. Zhang, G.-Y. Xu, J. Xuan,
Org. Lett., 2020, 22, 5984-5989.
A tandem nitrosation/cyclization reaction of N-aryl cyanoacetamides with
tert-butyl nitrite provides quinoxalin-2-ones in good yields with good
functional group tolerance. The dehydrogenative N-incorporation is
achieved through a sequence of nitrosation, tautomerization, and cyclization.
F. Wang, B.-L. Hu, L. Liu, H.-Y. Tu, X.-G. Zhang, J. Org. Chem.,
2017, 82, 11247-11252.
Selectfluor promotes an oxidative coupling of quinoxalin-2(1H)-ones with
alcohols, amines, thiols at the C3-position under metal- and photocatalyst-free
conditions. The method offers a broad substrate scope including bioactive
molecules, mild reaction conditions, readily available coupling partners, high
yields, scalability and step-economy.
Sonam, V. N. Shinde, K. Rangan, A. Kumar, J. Org. Chem., 2023, 88,
2344-2357.
A facile and effective alkoxylation of quinoxalin-2(1H)-ones with
primary or secondary alcohols via cross-dehydrogenative coupling under
catalyst-free conditions provides 3-alkoxylquinoxalin-2(1H)-ones in very
good yields in the presence of PhI(OTFA)2 as oxidant.
Q. Yang, X. Han, J. Zhao, H.-Y. Zhang, Y. Zhang, J. Org. Chem., 2019,
84, 11417-11424.
An efficient visible-light-induced C(sp2)-H/N-H
cross-dehydrogenative coupling (CDC)-amination with both primary and secondary
aliphatic amines allows the direct formation of 3-aminoquinoxalin-2(1H)-ones.
Preliminary mechanistic studies reveal that the reaction proceeds through a
radical process.
W. Wei, L. Wang, P. Bao, Y. Shao, H. Yue, D. Yang, X. Yang, X. Zhao, H. Wang, Org. Lett.,
2018, 20, 7125-7130.
An efficient visible-light-induced decarboxylative coupling reaction of
N-protected α-amino acids with heterocycles provides aminoalkylated heterocycles
in good yields. Attractive features of
this process include the generation of aminomethyl radical by an inexpensive
organic photocatalyst under transition-metal-free conditions.
Y. Li, C. Dai, S. Xie, P. Liu, P. Sun, Org. Lett., 2021, 23,
5906-5910.
Complexes of pyridyl glycosyl triazoles with Cu(I) salts were explored as
efficient catalysts to successfully assemble 2-amino-3-substituted and
3-substituted quinazolinones by domino/tandem cross-coupling reactions of
various N-substituted o-halobenzamides with cyanamide and
formamide, respectively.
S. K. Singh, S. Kumar, M. S. Yadav, V. K. Tiwari, J. Org. Chem., 2022, 87,
15389-15402.
A metal-free cross-dehydrogenative coupling between quinoxalinones and amines
in the presence of catalytic iodine and aqueous tert-butyl
hydroperoxide as the terminal oxidant provides 3-aminoquinoxalinones in good yields in dioxane as solvent. The reaction is highly versatile and
exhibits good functional group tolerance with a range of primary and secondary
amines.
A. Gupta, M. S. Deshmuk, N. Jain, J. Org. Chem.,
2017, 82, 4748-4792.
The use of trifluoromethyl thianthrenium salts enables high-yielding and
scalable trifluoromethylation reactions under visible light irradiation. A free
radical homolytic process is involved in this reaction, generating a key
trifluoromethyl radical intermediate.
Y. Li, X. Liang, K. Niu, J. Gu, F. Liu, Q. Xia, Q. Wang, W. Zhang, Org. Lett.,
2022, 24, 5918-5923.
DABCO serves as a sulfur-activating catalyst to achieve the sulfurative 1,2-diamination of
phenylacetylenes with elemental sulfur and o-phenylenediamines in the
presence of DMSO as terminal oxidant. This cascade three-component reaction is triggered by the addition of active sulfur species to the triple
bond of phenylacetylenes.
T. M. C. Tran, N. D. Lai, T. T. T. Bui, D. H. Mac, T. T. T. Nguyen, P.
Retailleau, T. B. Nguyen, Org. Lett., 2023, 25,
7186-7191.