Categories: Synthesis of N-Heterocycles > benzo-fused N-Heterocycles >
Synthesis of isoindolinones
Recent Literature
The use of a simple undivided cell with carbon electrodes enables an
efficient and practical electrochemical reduction of cyclic imides at room
temperature to provide hydroxylactams and lactams in a controllable manner,
tuned by electric current and reaction time. The reaction exhibits broad
substrate scope and high functional group tolerance.
Y. Bai, L. Shi, L. Zheng, S. Ning, X. Che, Z. Zhang, J. Xiang, Org. Lett., 2021, 23,
2298-2302.
Various N-substituted isoindolinones can be synthesized in
excellent yields through the reductive C-N coupling and intramolecular amidation
of 2-carboxybenzaldehyde with amines in the presence of ultrathin Pt nanowires
as catalysts under 1 bar of hydrogen. These unsupported catalysts can also be
used for the synthesis of phthalazinones in high yield when hydrazine or phenyl
hydrazine is used instead of amines.
L. Shi, L. Hu, J. Wang, X. Cao, H. Gu, Org. Lett., 2012,
14, 1876-1879.
A copper-catalyzed sp3 C-H functionalization of 2-alkyl-N-substituted
benzamides provides an efficient approach to various functionalized
isoindolinones without preparation of halogenated substitutes, use of expensive
transition metals, or toxic Sn or CO gas.
K. Nozawa-Kumada, J. Kadokawa, T. Kameyama, Y. Kondo, Org. Lett.,
2015,
17, 4479-4481.
A palladium-catalyzed C-H carbonylation of readily available free primary
benzylamines, in which NH2 acts as a chelating group, provides
benzolactams under an atmospheric pressure of CO. Application of this new method
is exemplified in the concise syntheses of two bioactive molecules.
C. Zhang, Y. Ding, Y. Gao, S. Li, G. Li, Org. Lett.,
2018, 20, 2595-2598.
A palladium-catalyzed C-H carbonylation of benzylamines provides
isoindolinone scaffolds in good yields under gas-free conditions by using
benzene-1,3,5-triyl triformate (TFBen) as a convenient CO surrogate.
L-Y. Fu, J. Ying, X. Qi, J.-B. Peng, X.-F. Wu, J. Org. Chem., 2019, 84,
1238-1246.
The merger of strain-release of 1,2-oxazetidines with carboxylic acid
directed C-H activation enables a catalytic synthesis of a range of structurally
diverse isoindolinones from readily available benzoic acids.
X.-Q. Hu, Z.-K. Liu, Y.-X. Hou, J.-H. Xu, Y. Gao, Org. Lett., 2021, 23,
6332-6336.
2-Benzyl-N-tosylbenzamides and related substrates undergo
copper-catalyzed intramolecular benzylic sulfamidation to provide N-arylsuflonyl-1-arylisoindolinones.
R. B. Bedford, J. G. Bowen, C. Méndez-Gálvez, J. Org. Chem.,
2017, 82, 1719-1725.
A new type of C2-symmetric chiral diene ligand was applied
successfully in the Rh-catalyzed asymmetric arylation of N-tosylarylimines
with arylboronic acids to give a broad range of highly enantiomerically enriched
diarylmethylamines as well as 3-aryl substituted phthalimidines.
Z.-Q. Wang, C.-G. Feng, M.-H. Xu, G.-Q. Lin, J. Am. Chem. Soc., 2007,
129, 5336-5337.
Electronically tunable cyclopentadienyl ligands enable a unprecedented
Rh-catalyzed enantioselective [4+1] annulation reaction of benzamides and
alkenes with a broad substrate scope under mild reaction conditions, providing a
variety of isoindolinones with excellent regio- and enantioselectivity.
W.-J. Cui, Z.-J. Wu, Q. Gu, S.-L. You, J. Am. Chem. Soc.,
2020, 142, 7379-7385.
Addition of o-iodobenzoyl chlorides to imines affords N-acyliminium
ions as adducts. Subsequent reaction of these adducts with phenyllithium at
-78˚C followed by warming to ambient temperature induces an intramolecular
Wurtz-Fittig coupling to afford 2,3-dihydroisoindolones in excellent yields.
J. B. Campbell, R. F. Dedinas, S. Trumbower-Walsh, Synlett, 2010,
3008-3010.
N-Heterocyclic nitrenium (NHN) salts, the analogues of N-heterocyclic carbenes,
can serve as catalytic electron acceptors for charge transfer complex
photoactivations. Under blue light irradiation, NHN salts catalyze the
generation of aryl radicals from aryl halides.
K.-Q. Chen, B.-B. Zhang, Z.-X. Wang, X.-Y. Chen, Org. Lett.,
2022, 24, 4598-4602.
An acylation/arylation reaction of α-aminoboronate salts with 2-bromobenzoyl
chlorides provides isoindolinones in very good yields under mild conditions via
an intramolecular, Cu-catalyzed sp3-sp2 coupling.
A. M. Dumas, A. J. Sieradzki, L. J. Donnelly, Org. Lett., 2016, 18,
1848-1851.
Copper(II) trifluoromethanesulfonate efficiently catalyzes the C-C coupling of
3-hydoxyisoindolinones with various aryl-, heteroaryl-, and alkenylboronic acids
to furnish C(3)-substituted isoindolinones in
1,2-dicholoroethane (DCE) at reflux. The photolabile 2-nitrobenzyl protecting
group is most appropriate for promotion of the coupling reaction and for
deprotection.
H. S. P. Rao, A. V. B. Rao, J. Org. Chem.,
2015,
80, 1506-1516.
A nickel-catalyzed reductive dicarbofunctionalization of
1,1-disubstituted enamides with unactivated alkyl iodides provides
3,3-dialkyl-substituted isoindolinones. This tandem cyclization/reductive
tolerates a broad range of functional groups. The use of a chiral Bn-Biox ligand
induces excellent enantioselectivities.
K. Fang, W. Huang, C. Shan, J. Qu, Y. Chen, Org. Lett., 2021, 23,
5523-5527.
A nickel-catalyzed reductive dicarbofunctionalization of
1,1-disubstituted enamides with unactivated alkyl iodides provides
3,3-dialkyl-substituted isoindolinones. This tandem cyclization/reductive
tolerates a broad range of functional groups. The use of a chiral Bn-Biox ligand
induces excellent enantioselectivities.
K. Fang, W. Huang, C. Shan, J. Qu, Y. Chen, Org. Lett., 2021, 23,
5523-5527.
A highly efficient palladium-catalyzed asymmetric tandem aza-Heck/Sonogashira
coupling reaction of O-phenyl hydroxamic ethers with terminal alkynes
provides challenging chiral isoindolinone derivatives bearing a quaternary
stereogenic center with excellent enantioselectivity under mild conditions. This
Pd-catalyzed aminoalkynylation reaction shows broad functional group tolerance.
L. Wang, Y. Wang, S. Wu, C.-G. Yan, C. Zhang, J. Zhang, Y. Han, J. Am. Chem. Soc.,
2024, 146, 4320-4026.
A metal-free tandem cyclization reaction for the synthesis of
3-methyleneisoindolin-1-ones starting from ester-functionalized aziridines is
effectively promoted by DBU and carboxylic acids. Mechanistically, it involves
sequential ring opening of aziridines with carboxylic acids, lactamization, and
elimination of carboxylic acids.
S. Xing, C. Jin, P. Zhang, J. Yang, Y. Liang, X. Ao, W. Pi, K. Wang, B. Zhu, J. Org. Chem., 2024, 89,
5153-5158.
An efficient palladium-catalyzed intramolecular cyclization of 2-iodobenzamides
with a 2-oxoethyl function group on the nitrogen atom moiety provides 3-acyl
isoindolin-1-ones and 3-hydroxy-3-acylisoindolin-1-ones under mild conditions in
good yields.
W. Chen, L. Jin, Y. Zhu, X. Cao, L. Zheng, W. Mo, Synlett, 2013, 24,
1856-1860.
An iridium-catalyzed oxidative annulation of benzamides with cyclopropanols
as C1 synthon provides structurally diverse isoindolin-1-ones via sequential
C-H/C-C cleavage and C-C/C-N bond formation.
S. Xu, C. Luo, K. Yan, J. Li, R. Lai, L. Hai, M. Guan, Y. Wu, Synthesis, 2022, 54,
3015-3024.
A N-heterocyclic carbene (NHC)-catalyzed synthesis of N-substituted
isoindolinone acetates proceeds through a tandem imine umpolung-intramolecular
aza-Michael addition followed by oxidation with molecular oxygen in air as the
sole oxidant. This method offers atom efficiency, operational simplicity,
large-scale syntheses, and mild reaction conditions.
J. Ramarao, P. C. Behera, M. S. Reddy, S. Suresh, J. Org. Chem., 2024, 89,
414-424.
A regioselective visible-light-mediated denitrogenative alkene insertion of
1,2,3-benzotriazin-4(3H)-ones provides 3-substituted isoindolinones. The
photocatalytic reaction is compatible with activated terminal alkenes and cyclic
α,β-unsaturated esters and ketones, with wide functional group tolerance for
N-substitution of the 1,2,3-benzotriazin-4(3H)-ones.
F. R. B. Bokosi, O. J. Shiels, C. Richardson, A. J. Trevitt, S. T. Keaveney, J. Org. Chem., 2024, 89,
1777-1783.
A cascade reaction enables a regiospecific synthesis of substituted
3-hydroxyisoindolinones under transition-metal-free conditions via base-mediated
C-C bond coupling and N-α-sp3C-H bond hydroxylation. The
procedure offers high regioselectivity, efficiency, and environmental
friendliness. Various substituted 3-hydroxyisoindolinones, including some
bioactive molecules, were provided in very good yields.
J. Shen, Q. You, Q. Fu, C. Kuai, H. Huang, L. Zhao, Z. Zhuang, Org. Lett.,
2017, 19, 5170-5173.
A metal-free photoredox catalyzed amidyl N-centered radical addition to the
C-C triple bond of o-alkynylated benzamides provides isoquinoline-1,3,4(2H)-triones,
3-hydroxyisoindolin-1-ones, and phthalimides via a proton-coupled electron
transfer (PCET) process under mild reaction conditions.
M. B. Reddy, K. Prasanth, R. Anandhan, Org. Lett.,
2022, 24, 3674-3679.
Pd-Catalyzed Aminocarbonylation of the Blaise Reaction Intermediate: One-Pot
Synthesis of (Z)-3-Methyleneisoindolin-1-ones from Nitriles
Z. Xuan, D. J. Jung, H. J. Jeon, S.-g. Lee, J. Org. Chem.,
2016, 81, 10094-10098.