Diastereoselective Construction of Eight-Membered Carbocycles through Palladium-Catalyzed C(sp3)-H Functionalization

Article abstract of DOI:10.1021/acs.orglett.0c04244

A palladium-catalyzed cross-coupling reaction of 2-alkylphenyl bromides with biphenylene has been developed. The reactions formed eight-membered carbocycles through C(sp3)-H activation and the formation of two C-C bonds, and the chiral products were obtai

Full text of DOI:10.1021/acs.orglett.0c04244

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Letter
Diastereoselective Construction of Eight-Membered Carbocycles
through Palladium-Catalyzed C(sp3)−H Functionalization
Bin Wan, Zhuoer Lu, Zhuo Wu, Cang Cheng, and Yanghui Zhang*
Cite This: Org. Lett. 2021, 23, 1269−1274
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ABSTRACT: A palladium-catalyzed cross-coupling reaction of 2-alkylphenyl bromides with biphenylene has been developed. The
reactions formed eight-membered carbocycles through C(sp3)−H activation and the formation of two C−C bonds, and the chiral
products were obtained with excellent diastereoselectivity. The reaction provides a new strategy for the construction of eight-
membered carbocycles, and the products represent a novel type of chiral scaffold.
Scheme 1. Reactions of Aryl Bromides with Biphenylene
ight-membered carbocycles are essential structural motifs
Ethat are ubiquitous in natural products, and the majority
of these natural cyclooctanoid compounds exhibit important
biological and medicinal properties (Figure 1).1 For instance,
taxol is one of the most potent anticancer drugs, and it is being
extensively used to treat a variety of human cancers.2 Notably,
dibenzocyclooctadiene lignans, a main subclass of lignans, are
eight-membered carbocycles containing a chiral biaryl axis.3
This class of natural products has been found to exhibit a wide
variety of biological activities.3c However, methods for the
construction of eight-membered carbocycles are still limited,
and most of the current methods involve intramolecular
cyclization from acyclic precursors.4 These methods are usually
challenging due to the unfavorable entropy effect and
transannular interactions.1a Furthermore, the acyclic precursors
essentially have the same level of structural complexity as the
carbocycles to be synthesized; therefore, the syntheses of the
precursors typically require multisteps. This challenge can be
addressed by intermolecular reactions, which may start from
relatively simple starting materials. Although some intermo-
lecular cycloaddition reactions have been developed for the
synthesis of eight-membered carbocycles, they are primarily
limited to the reactions of alkenes and alkynes, which restricts
Received: December 23, 2020
Published: February 9, 2021
Figure 1. Representative natural products containing eight-membered
carbocycles.
https://dx.doi.org/10.1021/acs.orglett.0c04244
© 2021 American Chemical Society
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a
Table 1. Optimization of Reaction Conditions
Scheme 3. Diastereoselective Synthesis of Chiral Eight-
a
Membered Carbocycles
entry
base
ligand
additive
solvent
DMA
yield (%)
1
2
3
4
5
6
7
8
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
Na2CO3
Cs2CO3
KOAc
K3PO4
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
P(o-tol)3
P(o-tol)3
P(o-tol)3
n-Bu4NBr
70
56
54
48
33
47
28
50
53
60
52
67
51
NR
50
64
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMF
NMP
n-Bu4NCl
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
n-Bu4NBr
PPh3
P(p-tol)3
PCy3
P(o-tol)3
P(o-tol)3
P(o-tol)3
P(o-tol)3
P(o-tol)3
P(o-tol)3
P(o-tol)3
P(o-tol)3
P(o-tol)3
9
10
11
12
13
14
15
1,4-dioxane
CH3CN
DMF
b
16
a
1
Yields were determined by H NMR analysis of the crude reaction
b
mixture using CH2Br2 as the internal standard. 5 mol % Pd(OAc)2
and 10% P(o-tol)3
a
Scheme 2. Substrate Scope
a
b
c
Isolated yield. 1 mmol of 1j was used. 0.1 mmol of 1j and 0.1
mmol of 2,3,6,7-tetramethylbiphenylene were used.
Scheme 4. Transformation of Cyano Groups
the scope of accessible products.1b,5 Therefore, it is still highly
desirable to develop new synthetic strategies for eight-
membered carbocycles, in particular, those through intermo-
lecular reactions.
C−H functionalization represents an innovative tactic for
organic synthesis.6 Whereas C(sp2)−H activation reactions
have been extensively exploited, C(sp3)−H functionalization is
still underdeveloped because it is more challenging.7
Directing groups are often used to achieve high
regioselectivity in transition-metal-catalyzed C−H functional-
ization reactions.8 However, this strategy needs additional
steps to introduce and transform the directing groups.
Remarkably, halogens have been exploited as traceless
directing groups to assist the cleavage of C−H bonds. For
Pd-catalyzed halogen-assisted C−H activation reactions, C,C-
a
Isolated yield
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Scheme 5. Mechanistic Studies
Scheme 7. Proposed Mechanism
Scheme 6. Kinetic Isotope Effect Studies
In 2006, the Gallagher group reported a very intriguing
cross-coupling reaction of 2-4-aryl-3-bromopyridines with
biphenylene (Scheme 1a).13 The reactions involved C(sp2),C-
(sp2)-palladacycles obtained from bromo-directed C(sp2)−H
activation and formed eight-membered heterocyclic tetraphe-
nylenes. Although only three examples were studied and the
yields were low in Gallagher’s reactions, the reactions provided
a strategy for the construction of eight-membered rings.
Inspired by this elegant reaction, we envisioned that C(sp2),C-
(sp3)-palladacycles derived by the C(sp3)−H activation of aryl
halides could also undergo a coupling reaction with
biphenylene. However, C(sp3)−H activation is more challeng-
ing, and it has also been reported that aryl halides tend to
undergo homocoupling via Pd-catalyzed C(sp3)−H activa-
tion.14 To develop the cross-coupling of C(sp3)−H bonds of
aryl halides with biphenylene, these challenges have to be
addressed. Herein we report the cross-coupling reaction of aryl
bromides and biphenylene via C(sp3)−H activation. This
reaction represents an innovative method for the diaster-
eoslective construction of eight-membered carbocycles
(Scheme 1b).
We first investigated the reaction of 1-bromo-2-(tert-
butyl)benzene (1a) and biphenylene (2). After an extensive
conditions survey, we obtained the desired eight-membered
product 3a in 70% yield under the conditions shown in Table 1
(entry 1). Removing n-Bu4NBr or using n-Bu4NCl led to a
lower yield (entries 2 and 3). The yield also decreased in the
absence of P(o-tol)3 or in the presence of other phosphine
ligands (entries 4−7). The survey of other inorganic bases
revealed that K2CO3 was the optimal base (entries 8−11).
Furthermore, the reaction proceeded less efficiently in DMF,
NMP, and CH3CN and failed to give 3a in 1,4-dioxane (entries
12−15). Notably, a yield of 64% was still obtained using 5 mol
% of Pd(OAc)2 and 10 mol % of P(o-tol)3 (entry 16).
Having identified the optimal conditions for the synthesis of
eight-membered carbocycles, we investigated the substrate
scope of the cross-coupling reaction. The reactions of 1-
bromo-2-(tert-butyl)benzene derivatives were first probed. As
shown in Scheme 2, the substrates bearing a methyl or tert-
butyl group at the five-position generated the corresponding
products in moderate yields (3b and 3c). A chloro group was
palladacycles are formed.9 Our group has a long-standing
interest in palladacycles because their unique structures and
novel reactivities can be utilized to develop innovative and
synthetically useful organic transformations.10 Notably, Pd-
catalyzed C(sp3)−H activation can also be enabled by utilizing
halogens as traceless directing groups, which forms C(sp2),C-
(sp3)-palladacycles. The majority of the current C(sp3)−H
activation reactions of such type involve intramolecular
cyclization,11 and intermolecular functionalization is under-
exploited.10,12
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tolerated, yet the yield was low (3d). The substrate bearing an
electron-withdrawing ester group was also suitable, but the
reaction was low-yielding (3e). Intriguingly, four- or six-
substituted substrates (1f and 1g) gave the same product 3f.
The formation of 3f in the reaction of 1g should be caused by
palladium migration. (For the detailed mechanism, see the
Supporting Information.) Whereas the activated C(sp3)−H
bonds are from tert-butyl groups for the above substrates, the
reactivity of C(sp3)−H bonds from other groups was also
examined. Gratifyingly, bromobenzenes bearing a dimethoxy-
substituted tert-butyl group or a 1,3-dioxolanyl group also
successfully coupled to biphenylene, albeit in low yields (3h
and 3i).
1a-C could react with biphenylene to form product 3a
(Scheme 5, reaction 1). Furthermore, it has been reported that
Ni(2,2-biphenyl) tends to undergo homocoupling to form
tetraphenylene.16 To examine if the reactions involved the
cross-coupling of two palladacycles, we also prepared complex
2-C. When palladacycle 1a-C was allowed to react with 2-C,
product 3a was not observed (reaction 2). Complex 2-C also
failed to react with 1a (reaction 3). Although the cross-
coupling of two palladacycles could not be excluded, these
experimental results support the notion that C(sp2),C(sp3)-
palladacycles were the intermediates and they reacted with
biphenylene to generate eight-membered carbocycle products.
Kinetic isotope effects (KIEs) in the reaction were also
studied. Deuterated substrates 1j-D3 and 1j-D6 were prepared.
When 1j-D3 was subjected to the standard conditions,
products 3j-D3 and 3j-D2 were obtained in a ratio of 5.0 to
1, which indicates that the intramolecular KIE is 5.0.
Furthermore, parallel reactions of 3j and 3j-D6 were
conducted. 3j and 3j-D6 were allowed to react with 2,
respectively, under standard conditions for different periods of
time, and the KIE value was obtained as 3.45 (Scheme 6).
These KIE values imply that C(sp3)−H activation should be
the rate-determining step.
Therefore, a mechanism was proposed for the formation of
3a (Scheme 7). The reaction is initiated by the oxidative
addition of 1a to Pd0 species, which yields PdII species A. The
PdII species activates the C(sp3)−H bond to form palladacycle
B. The oxidative addition of biphenylene 2 to palladacycle B
affords PdIV species C. The subsequent reductive elimination
of PdIV species C gives two possible nine-membered
palladacycles D-1 and D-2. Finally, a second reductive
elimination generates product 3a and the Pd0 species.
In conclusion, we have developed a palladium-catalyzed
cross-coupling reaction of 2-alkylphenyl bromides with
biphenylene through C(sp3)−H activation. The reaction
forms eight-membered carbocycles as the products with
excellent diastereoselectivity. Mechanistic studies revealed
that palladacycles formed by C(sp3)−H activation should act
as the key intermediates. The reaction provides an innovative
strategy for the synthesis of eight-membered carbocycles, and
the products represent a novel type of chiral scaffold.
It is noted that the previously mentioned eight-membered
carbocycle products are chiral. Actually, product 3a contains
two enantiomers, and they are separable by HPLC. (See the
Supporting Information.) The eight-membered carbocycle
represents a novel type of chiral skeleton and may find
applications in various fields such as asymmetric synthesis and
materials science. For example, dibenzocyclooctadiene lignans
are chiral eight-membered carbocycles.3 Therefore, we set out
to study the stereoselectivity of the cross-coupling reaction. We
first examined the reaction of 1-bromo-2-(2-cyano-isopropyl)-
benzene (1j). Substrate 1j bears two methyl groups. When one
of the two methyl groups is functionalized, a new chiral centers
will be created. Remarkably, 1j reacted with 2 under the
standard conditions to form the eight-membered product 3j in
quantitative yield (Scheme 3). More intriguingly, the reaction
was highly diastereoselective, and only a pair of enantiomers
was obtained. The two enantiomers of 3j were also separable
by HPLC (see the Supporting Information), and the structure
of 3j was identified by single-crystal X-ray crystallography. The
molecule has a very intriguing structure. The two opposite
benzene rings are located above the average plane of the eight-
membered ring, and the other benzene ring is below the plane.
Next, the reactions of the derivatives of 1j were probed
(Scheme 3). The derivatives bearing an electron-donating
methyl or electron-withdrawing trifluoromethyl group at the
position meta to the bromo group were suitable (3k and 3l).
Although the yields decreased, the diastereoselectivities were
still excellent. Both fluoro and chloro groups were tolerated,
yet the reactions were far lower yielding (3m and 3n). Para-
and disubstituted derivatives were also reactive, and the
corresponding products were formed in good or excellent
yields (3o−3q). In these reactions, only enantiomers were
obtained. When chiral substrates were used, the reactions were
still highly diastereoselective, forming a pair of enantiomers in
almost quantitative yields (3r−3u). Notably, the yield of the
reaction of 1j and 2,3,6,7-tetramethylbiphenylene was
moderate, and only enantiomers were obtained (3v).
ASSOCIATED CONTENT
■
sı
* Supporting Information
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.orglett.0c04244.
The cyano group could be transformed in multiple ways. For
instance, it could be reduced to an amino group (Scheme 4).
The amino group can be readily manipulated to allow for
further functionalization.
Detailed experimental procedures, crystallographic data
of compound 3j, HPLC data of compounds 3a and 3j,
and characterization data and NMR spectra of all
products and new substrate (PDF)
Mechanistically, it has been proposed that palladacycle
Pd(2,2′-biaryl)s could react with biphenylene to form
tetraphenylenes in the cross-coupling of 3-bromo-4-phenyl-
pyridines with biphenylene and the homocoupling of
biphenylene.13,15 However, the coupling of C(sp2),C(sp3)-
palladacycles with biphenylene has not been reported. To
obtain evidence to support the notion that palladacycles also
acted as the intermediates in the coupling reaction of C(sp3)−
H bonds with biphenylenes, we prepared palladacycle 1a-C.
Accession Codes
CCDC 2045337 contains the supplementary crystallographic
data for this paper. These data can be obtained free of charge
via www.ccdc.cam.ac.uk/data_request/cif, or by emailing
data_request@ccdc.cam.ac.uk, or by contacting The Cam-
bridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
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(6) (a) C−H Activation; Yu, J.-Q., Shi, Z., Eds.; Springer:
Heidelberg, Germany, 2010. (b) Zhang, Y.-H.; Shi, G.-F.; Yu, J.-Q.
Carbon-Carbon-Bond Formation via C−H Bond Functionalization.
In Comprehensive Organic Synthesis, 2nd ed.; Molander, G., Knochel,
P., Eds.; Elsevier: Oxford, U.K., 2014; Vol. 3, pp 1101−1209. (c) Liu,
C.; Yuan, J.-W.; Gao, M.; Tang, S.; Li, W.; Shi, R.-Y.; Lei, A.-W. Chem.
Rev. 2015, 115, 12138−12204. (d) Lyons, T. W.; Sanford, M. S.
Chem. Rev. 2010, 110, 1147−1169. (e) Daugulis, O.; Roane, J.; Tran,
L. D. Acc. Chem. Res. 2015, 48, 1053−1064. (f) Miao, J.; Ge, H. Eur. J.
Org. Chem. 2015, 2015, 7859−7868. (g) Gensch, T.; Hopkinson, M.
N.; Glorius, F.; Wencel-Delord, J. Chem. Soc. Rev. 2016, 45, 2900−
2936. (h) Moselage, M.; Li, J.; Ackermann, L. ACS Catal. 2016, 6,
498−525. (i) Zhang, Q.; Shi, B.-F. Chin. J. Chem. 2019, 37, 647−656.
(j) Rej, S.; Ano, Y.; Chatani, N. Chem. Rev. 2020, 120, 1788−1887.
(7) (a) He, J.; Wasa, M.; Chan, K. S. L.; Shao, Q.; Yu, J.-Q. Chem.
Rev. 2017, 117, 8754−8786. (b) Xu, Y.; Dong, G.-B. Chem. Sci. 2018,
9, 1424−1432. (c) Chen, Z.; Rong, M.-Y.; Nie, J.; Zhu, X.-F.; Shi, B.-
F.; Ma, J.-A. Chem. Soc. Rev. 2019, 48, 4921−4942. (d) Li, B.-J.; Shi,
Z.-J. Chem. Soc. Rev. 2012, 41, 5588−5598. (e) Chu, J. C. K.; Rovis,
T. Angew. Chem., Int. Ed. 2018, 57, 62−101. (f) Jazzar, R.; Hitce, J.;
Renaudat, A.; Sofack-Kreutzer, J.; Baudoin, O. Chem. - Eur. J. 2010,
16, 2654−2672. (g) He, G.; Wang, B.; Nack, W. A.; Chen, G. Acc.
Chem. Res. 2016, 49, 635−645.
AUTHOR INFORMATION
■
Corresponding Author
Yanghui Zhang − School of Chemical Science and Engineering,
Shanghai Key Laboratory of Chemical Assessment and
Sustainability, Tongji University, Shanghai 200092, P. R.
China; orcid.org/0000-0003-2189-3496;
Email: zhangyanghui@tongji.edu.cn
Authors
Bin Wan − School of Chemical Science and Engineering,
Shanghai Key Laboratory of Chemical Assessment and
Sustainability, Tongji University, Shanghai 200092, P. R.
China
Zhuoer Lu − School of Chemical Science and Engineering,
Shanghai Key Laboratory of Chemical Assessment and
Sustainability, Tongji University, Shanghai 200092, P. R.
China
Zhuo Wu − School of Chemical Science and Engineering,
Shanghai Key Laboratory of Chemical Assessment and
Sustainability, Tongji University, Shanghai 200092, P. R.
China
Cang Cheng − School of Chemical Science and Engineering,
Shanghai Key Laboratory of Chemical Assessment and
Sustainability, Tongji University, Shanghai 200092, P. R.
China
(8) (a) Lyons, T. W.; Sanford, M. S. Chem. Rev. 2010, 110, 1147−
1169. (b) Engle, K. M.; Mei, T.-S.; Wasa, M.; Yu, J.-Q. Acc. Chem. Res.
2012, 45, 788−802. (c) Rousseau, G.; Breit, B. Angew. Chem., Int. Ed.
2011, 50, 2450−2494. (d) Zhang, F. Z.; Spring, D. R. Chem. Soc. Rev.
2014, 43, 6906−6919. (e) Chen, Z.-K.; Wang, B.-J.; Zhang, J.-T.; Yu,
W.-L.; Liu, Z.-X.; Zhang, Y.-L. Org. Chem. Front. 2015, 2, 1107−1295.
(f) Huang, Z.-X.; Lim, H.-N.; Mo, F.-Y.; Young, M. C.; Dong, G.-B.
Chem. Soc. Rev. 2015, 44, 7764−7786.
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.orglett.0c04244
(9) (a) Campo, M. A.; Huang, Q.; Yao, T.; Tian, Q.; Larock, R. C. J.
Am. Chem. Soc. 2003, 125, 11506−11507. (b) Hennessy, E. J.;
Buchwald, S. L. J. Am. Chem. Soc. 2003, 125, 12084−12085.
(c) Garcia-Cuadrado, D.; Braga, A. A. C.; Maseras, F.; Echavarren,
A. M. J. Am. Chem. Soc. 2006, 128, 1066−1067. (d) Campeau, L. C.;
Parisien, M.; Jean, A.; Fagnou, K. J. Am. Chem. Soc. 2006, 128, 581−
590. (e) Garcia-Cuadrado, D.; de Mendoza, P.; Braga, A. A. C.;
Maseras, F.; Echavarren, A. M. J. Am. Chem. Soc. 2007, 129, 6880−
6886. (f) Albicker, M. R.; Cramer, N. Angew. Chem., Int. Ed. 2009, 48,
9139−9142. (g) Shintani, R.; Otomo, H.; Ota, K.; Hayashi, T. J. Am.
Chem. Soc. 2012, 134, 7305−7308. (h) Gao, D.-W.; Yin, Q.; Gu, Q.;
You, S.-L. J. Am. Chem. Soc. 2014, 136, 4841−4844. (i) Deng, R.;
Huang, Y.; Ma, X.; Li, G.; Zhu, R.; Wang, B.; Kang, Y.-B.; Gu, Z. J.
Am. Chem. Soc. 2014, 136, 4472−4475. (j) Sickert, M.; Weinstabl, H.;
Peters, B.; Hou, X.; Lautens, M. Angew. Chem., Int. Ed. 2014, 53,
5147−5151. (k) Yang, Y.; Zhou, B.; Zhu, X.; Deng, G.; Liang, Y.;
Yang, Y. Org. Lett. 2018, 20, 5402−5405.
(10) (a) Wu, Z.; Ma, D.; Zhou, B.; Ji, X.-M.; Ma, X.-T.; Wang, X.-L.;
Zhang, Y.-H. Angew. Chem., Int. Ed. 2017, 56, 12288−12291. (b) Lu,
A.-L.; Ji, X.-M.; Zhou, B.; Wu, Z.; Zhang, Y.-H. Angew. Chem., Int. Ed.
2018, 57, 3233−3237. (c) Sun, X.-L.; Wu, Z.; Qi, W.-X.; Ji, X.-M.;
Cheng, C.; Zhang, Y.-H. Org. Lett. 2019, 21, 6508−6512. (d) Gu, Y.-
C.; Sun, X.-L.; Wan, B.; Lu, Z.-E.; Zhang, Y.-H. Chem. Commun. 2020,
56, 10942−10945.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
The work was supported by the National Natural Science
Foundation of China (nos. 21971196 and 21672162) and the
Shanghai Science and Technology Commission
(14DZ2261100).
REFERENCES
■
(1) (a) Hu, Y.-J.; Li, L.-X.; Han, J.-C.; Min, L.; Li, C.-C. Chem. Rev.
2020, 120, 5910−5953. (b) Yu, Z.-X.; Wang, Y.; Wang, Y.-Y. Chem. -
Asian J. 2010, 5, 1072−1088. (c) Faulkner, D. J. Nat. Prod. Rep. 1988,
5, 613−663.
(2) (a) Suffness, M. Taxol: Science and Applications; CRC Press:
Boca Raton, FL, 1995. (b) Kingston, D. G. I. J. Org. Chem. 2008, 73,
3975−3984.
(3) (a) Chang, J.-B.; Reiner, J.; Xie, J.-X. Chem. Rev. 2005, 105,
4581−4609. (b) Fang, X.-H.; Hu, X.-D. Molecules 2018, 23, 3385.
(c) Gao, X.-M.; Wang, R.-R.; Niu, D.-Y.; Meng, C.-Y.; Yang, L.-M.;
Zheng, Y.-T.; Yang, G.-Y.; Hu, Q.-F.; Sun, H.-D.; Xiao, W.-L. J. Nat.
Prod. 2013, 76, 1052−1057.
(11) (a) Baudoin, O. Acc. Chem. Res. 2017, 50, 1114−1123.
(b) Dyker, G. Angew. Chem., Int. Ed. 1999, 38, 1698−1712.
(c) Chaumontet, M.; Piccardi, R.; Audic, N.; Hitce, J.; Peglion, J.
L.; Clot, E.; Baudoin, O. J. Am. Chem. Soc. 2008, 130, 15157−15166.
(d) Rousseaux, S.; Davi, M.; Sofack-Kreutzer, J.; Pierre, C.; Kefalidis,
C. E.; Clot, E.; Fagnou, K.; Baudoin, O. J. Am. Chem. Soc. 2010, 132,
10706−10716. (e) Yan, J.-X.; Li, H.; Liu, X.-W.; Shi, J.-L.; Wang, X.;
Shi, Z.-J. Angew. Chem. 2014, 126, 5045−5049. (f) Wang, M.; Zhang,
X.; Zhuang, Y.-X.; Xu, Y.-H.; Loh, T.-P. J. Am. Chem. Soc. 2015, 137,
1341−1347.
(4) (a) Mehta, G.; Singh, V. Chem. Rev. 1999, 99, 881−930.
(b) Michaut, A.; Rodriguez, J. Angew. Chem., Int. Ed. 2006, 45, 5740−
5750. (c) Yet, L. Chem. Rev. 2000, 100, 2963−3007. (d) Petasis, N.
A.; Patane, M. A. Tetrahedron 1992, 48, 5757−5821. (e) Wang, Y.;
Yu, Z.-X. Acc. Chem. Res. 2015, 48, 2288−2296.
(5) (a) Fu, X.-F.; Xiang, Y.; Yu, Z.-X. Chem. - Eur. J. 2015, 21,
4242−4246. (b) Zhang, L.; Wang, Y.; Yao, Z.-J.; Wang, S.-Z.; Yu, Z.-
́
́
X. J. Am. Chem. Soc. 2015, 137, 13290−13300. (c) Julia-Hernandez,
F.; Ziadi, A.; Nishimura, A.; Martin, R. Angew. Chem., Int. Ed. 2015,
54, 9537−9541. (d) Yang, S.; Xu, Y.; Li, J. Org. Lett. 2016, 18, 6244.
(e) Kennedy, C. R.; Zhong, H. Y.; Macaulay, R. L.; Chirik, P. J. J. Am.
́
́
́
(12) (a) Gutiérrez-Bonet, A.; Julia-Hernandez, F.; de Luis, B.;
Martin, R. J. Am. Chem. Soc. 2016, 138, 6384−6387. (b) Tan, B.-J.;
Bai, L.; Ding, P.; Liu, J.-J.; Wang, Y.-Y.; Luan, X.-J. Angew. Chem.
̈
Chem. Soc. 2019, 141, 8557−8573. (f) Braconi, E.; Gotzinger, A. C.;
Cramer, N. J. Am. Chem. Soc. 2020, 142, 19819−19842.
1273
https://dx.doi.org/10.1021/acs.orglett.0c04244
Org. Lett. 2021, 23, 1269−1274

Organic Letters
pubs.acs.org/OrgLett
Letter
2018, 131, 1488−1492. (c) Cai, S.-L.; Li, Y.; Yang, C.; Sheng, J.;
Wang, X.-S. ACS Catal. 2019, 9, 10299−10304.
(13) Masselot, D.; Charmant, J. P. H.; Gallagher, T. J. Am. Chem.
Soc. 2006, 128, 694−695.
(14) (a) Dyker, G. Angew. Chem., Int. Ed. Engl. 1992, 31, 1023−
1025. (b) Dyker, G. Angew. Chem., Int. Ed. Engl. 1994, 33, 103−105.
(15) Edelbach, B. L.; Lachicotte, R. J.; Jones, W. D. J. Am. Chem. Soc.
1998, 120, 2843−2853.
(16) (a) Eisch, J. J.; Piotrowski, A. M.; Han, K. I.; Kruger, C.; Tsay,
̈
Y. H. Organometallics 1985, 4, 224−231. (b) Lu, Z.; Jun, C.-H.; de
Gala, S. R.; Sigalas, M. P.; Eisenstein, O.; Crabtree, R. H.
Organometallics 1995, 14, 1168−1175. (c) Perthuisot, C.; Edelbach,
B. E.; Zubris, D. L.; Jones, W. D. Organometallics 1997, 16, 2016−
2023.
1274
https://dx.doi.org/10.1021/acs.orglett.0c04244
Org. Lett. 2021, 23, 1269−1274