Journal of the American Chemical Society
Page 6 of 8
reaction mixtures. bd.r. = 2:1. c1.3 equiv ethyl acrylate was used. d1 equiv
diene was used.
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1
2
CONCLUSION
3
4
5
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8
9
In conclusion, we have demonstrated that alkyl carboxylic acids,
which represent inexpensive and widely available sources of
carbon frameworks, can be directly used to synthesize Heck-type
products. An extremely broad scope of substrates is accommodated
to give products in an external oxidant-free manner via the
synergistic merger of an organo photoredox catalyst and a
cobaloxime catalyst in the presence of a catalytic amount of base
under blue LED irradiation. Some of the synthesized alkenes such
as the vinyl silanes and vinyl boronates bearing a tertiary alkyl
substituent, and the three-component coupling products are
difficult to access by other means. The key to the success relies on
the unique proton/electron accepting ability of the cobaloxime
catalyst, which is beyond the capacity of conventional oxidants.
This dual-catalysis protocol features merits such as widely
available feedstocks, absence of both noble-metal and harmful by-
products, which will likely find broad applications in the synthesis
of valuable disubstituted alkenes and late-stage functionalization of
pharmacophores.
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decarboxylative functionalization of carboxylic acids and their derivatives.”
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Chem. Soc. 2014, 136, 11602. (c) Ramirez, N. P.; Gonzalez-Gomez, J. C.
“Decarboxylative Giese-type reaction of carboxylic acids promoted by
visible light: A sustainable and photoredox-neutral protocol.” Eur. J. Org.
Chem. 2017, 2154.
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(7) Wang, G.-Z.; Shang, R.; Fu, Y. “Irradiation-induced palladium-
catalyzed
decarboxylative
Heck
reaction
of
aliphatic
N-
(acyloxy)phthalimides at room temperature.” Org. Lett. 2018, 20, 888.
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Selective decarboxylative alkenylation of aliphatic carboxylic acids with
vinyl arenes enabled by photoredox/palladium/uphill triple catalysis.” Org.
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the photogeneration of hydrogen from water based on a platinum(II)
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42, 1995.
ASSOCIATED CONTENT
Supporting Information
This material is available free of charge via the Internet at
Experimental procedures and characterization data for all products,
additional comments on mechanism, computational details, Figures
S1-S26 and Tables S1-S11
AUTHOR INFORMATION
Corresponding Author
Notes
The authors declare no competing financial interests.
(12) Zhang, G.; Liu, C.; Yi, H.; Meng, Q.; Bian, C.; Chen, H.; Jian, J.-
X.; Wu, L.-Z.; Lei, A. “External oxidant-free oxidative cross-coupling: a
photoredox cobalt-catalyzed aromatic C-H thiolation for constructing CS
bonds.” J. Am. Chem. Soc. 2015, 137, 9273.
ACKNOWLEDGMENT
(13) (a) Zheng, Y.-W.; Chen, B.; Ye, P.; Feng, K.; Wang, W.; Meng, Q.-
Y.; Wu, L.-Z.; Tung, C.-H. “Photocatalytic hydrogen-evolution cross-
couplings: benzene CH amination and hydroxylation.” J. Am. Chem. Soc.
2016, 138, 10080. (b) Yang, Q.; Zhang, L.; Ye, C.; Luo, S.; Wu, L.-Z.
“Visible-light-promoted asymmetric cross-dehydrogenative coupling of
tertiary amines to ketones by synergistic multiple catalysis.” Angew. Chem.,
Int. Ed. 2017, 56, 3694. (c) Xiang, M.; Meng, Q.-Y.; Li, J.-X.; Zheng, Y.-
W.; Ye, C.; Li, Z.-J.; Chen, B.; Tung, C.-H.; Wu, L.-Z. “Activation of CH
bonds through oxidant-free photoredox catalysis: cross-coupling hydrogen-
evolution transformation of isochromans and β-keto esters.” Chem. Eur. J.
2015, 21, 18080. (d) Zhong, J.-J.; Meng, Q.-Y.; Liu, B.; Li, X.-B.; Gao, X.-
W.; Lei, T.; Wu, C.-J.; Li, Z.-J.; Tung, C.-H.; Wu, L.-Z. “Cross-coupling
hydrogen evolution reaction in homogeneous solution without noble
metals.” Org. Lett. 2014, 16, 1988. (e) Meng, Q.-Y.; Zhong, J.-J.; Liu, Q.;
Gao, X.-W.; Zhang, H.-H.; Lei, T.; Li, Z.-J.; Feng, K.; Chen, B.; Tung, C.-
H.; Wu, L.-Z. “A cascade cross-coupling hydrogen evolution reaction by
visible light catalysis.” J. Am. Chem. Soc. 2013, 135, 19052.
(14) (a) Zhang, G.; Hu, X.; Chiang, C.-W.; Yi, H.; Pei, P.; Singh, A. K.;
Lei, A. “Anti-Markovnikov oxidation of β-alkyl styrenes with H2O as the
terminal oxidant.” J. Am. Chem. Soc. 2016, 138, 12037. (b) Zhang, G.;
Zhang, L.; Yi, H.; Luo, Y.; Qi, X.; Tung, C.-H.; Wu, L.-Z.; Lei, A. “Visible-
light induced oxidant-free oxidative cross-coupling for constructing allylic
sulfones from olefins and sulfinic acids.” Chem. Commun. 2016, 52, 10407.
(c) Yi, H.; Niu, L.; Song, C.; Li, Y.; Dou, B.; Singh, A. K.; Lei, A. “Phot-
catalytic dehydrogenative cross-coupling of alkenes with alcohols or azoles
without external oxidant.” Angew. Chem., Int. Ed. 2017, 56, 1120. (d) Niu,
L.; Yi, H.; Wang, S.; Liu, T.; Liu, J.; Lei, A. “Photo-induced oxidant-free
oxidative CH/NH cross-coupling between arenes and azoles.” Nat.
Commun. 2017, 8, 14226. (e) Hu, X.; Zhang, G.; Bu, F.; Lei, A. “Selective
We are grateful for the financial support provided by the
National University of Singapore and the Ministry of Education
(MOE) of Singapore (R-143-000-665-114, R-143-000-696-114, R-
143-000-A30-112), GSK-EDB (R-143-000-687-592) and National
Natural Science Foundation of China (Grant No. 21702142).
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