Organic Letters
Letter
(c) New Trends in Cross-Coupling; Colacot, T. J., Ed.; The Royal
Society of Chemistry: Cambridge, 2015.
Notes
The authors declare no competing financial interest.
(6) For representative examples, see: (a) Yin, J.; Rainka, M. P.;
Zhang, X. X.; Buchwald, S. L. A Highly Active Suzuki Catalyst for the
Synthesis of Sterically Hindered Biaryls: Novel Ligand Coordination.
J. Am. Chem. Soc. 2002, 124, 1162−1163. (b) Altenhoff, G.; Goddard,
R.; Lehmann, C. W.; Glorius, F. An N-Heterocyclic Carbene Ligand
with Flexible Steric Bulk Allows Suzuki Cross-Coupling of Sterically
Hindered Aryl Chlorides at Room Temperature. Angew. Chem., Int.
Ed. 2003, 42, 3690−3693. (c) Chen, M. T.; Vicic, D. A.; Turner, M.
L.; Navarro, O. (N-Heterocyclic Carbene)PdCl2(TEA) Complexes:
Studies on the Effect of the “Throw-Away” Ligand in Catalytic
Activity. Organometallics 2011, 30, 5052−5056. (d) Wu, L.; Drinkel,
E.; Gaggia, F.; Capolicchio, S.; Linden, A.; Falivene, L.; Cavallo, L.;
Dorta, R. Room-Temperature Synthesis of Tetra-ortho-Substituted
Biaryls by NHC-Catalyzed Suzuki−Miyaura Couplings. Chem. - Eur. J.
2011, 17, 12886−12890. (e) Chartoire, A.; Lesieur, M.; Falivene, L.;
Slawin, A. M. Z.; Cavallo, L.; Cazin, C. S. J.; Nolan, S. P.
[Pd(IPr*)(cinnamyl)Cl]: An Efficient Pre-catalyst for the Preparation
of Tetra-ortho-substituted Biaryls by Suzuki−Miyaura Cross-Cou-
pling. Chem. - Eur. J. 2012, 18, 4517−4521.
ACKNOWLEDGMENTS
■
Rutgers University and the NSF (CAREER CHE-1650766)
are gratefully acknowledged for support. The Bruker 500 MHz
spectrometer was supported by an NSF-MRI grant (CHE-
1229030). We thank the Wroclaw Center for Networking and
Supercomputing (Grant No. WCSS159).
REFERENCES
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to toxic stannanes. (4) The only examples of the synthesis of bis-
ortho,ortho-substituted ketones from acyl chlorides (but not amides)
via Suzuki cross-coupling are as follows: boronic acids (50% yield),
organotrifluoroborates (38%), and boronic acids using designer
phosphinoferrocene ligands with extended urea-amide substituents
(55%).7a,b Thus, at present, there are no general methods for the
assembly of sterically hindered ketones by the Suzuki−Miyaura cross-
coupling of acyl electrophiles.
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X.; Mao, Y.; Han, J.; Wang, Y.; Yang, H.; Pan, Y. Ni-catalyzed
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via C−N bond activation. Sci. Adv. 2019, 5, 9516. (e) Yuan, S. W.;
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C−H Amidation of (Hetero)arenes to Produce Amides through
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N-Heterocyclic Carbene) Precatalysts for Cross-Coupling Reactions
of Amides and Esters by Selective Acyl CO−X (X = N, O) Cleavage.
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Yamaguchi, J. Cross-Coupling of Aromatic Esters and Amides. Chem.
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̈
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E
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