Copper-Catalyzed Enantioconvergent Radical Suzuki-Miyaura C(sp3)-C(sp2) Cross-Coupling

Article abstract of DOI:10.1021/jacs.0c09125

A copper-catalyzed enantioconvergent Suzuki-Miyaura C(sp3)-C(sp2) cross-coupling of various racemic alkyl halides with organoboronate esters has been established in high enantioselectivity. Critical to the success is the use of a chiral cinchona alkaloid-derived N,N,P-ligand for not only enhancing the reducing capability of copper catalyst to favor a stereoablative radical pathway over a stereospecific SN2-type process but also providing an ideal chiral environment to achieve the challenging enantiocontrol over the highly reactive radical species. The reaction has a broad scope with respect to both coupling partners, covering aryl- and heteroarylboronate esters, as well as benzyl-, heterobenzyl-, and propargyl bromides and chlorides with good functional group compatibility. Thus, it provides expedient access toward a range of useful enantioenriched skeletons featuring chiral tertiary benzylic stereocenters.

Full text of DOI:10.1021/jacs.0c09125

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Article
Copper-Catalyzed Enantioconvergent Radical Suzuki−Miyaura
C(sp3)−C(sp2) Cross-Coupling
Sheng-Peng Jiang, Xiao-Yang Dong, Qiang-Shuai Gu, Liu Ye, Zhong-Liang Li,* and Xin-Yuan Liu*
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ABSTRACT: A copper-catalyzed enantioconvergent Suzuki−
Miyaura C(sp3)−C(sp2) cross-coupling of various racemic alkyl
halides with organoboronate esters has been established in high
enantioselectivity. Critical to the success is the use of a chiral
cinchona alkaloid-derived N,N,P-ligand for not only enhancing the
reducing capability of copper catalyst to favor a stereoablative
radical pathway over a stereospecific SN2-type process but also
providing an ideal chiral environment to achieve the challenging enantiocontrol over the highly reactive radical species. The reaction
has a broad scope with respect to both coupling partners, covering aryl- and heteroarylboronate esters, as well as benzyl-,
heterobenzyl-, and propargyl bromides and chlorides with good functional group compatibility. Thus, it provides expedient access
toward a range of useful enantioenriched skeletons featuring chiral tertiary benzylic stereocenters.
elegantly established to realize the enantioconvergent Suzuki−
Miyaura C(sp3)−C(sp2) coupling of (sulfon)amide-substituted
alkyl halides or trifluoromethoxyl-substituted benzylic halides,
a strategy pioneered by Fu (Scheme 1A).7,8 Recently,
Nakamura disclosed a chiral iron/bisphosphine catalyst to
realize the coupling of racemic α-bromopropionate, albeit with
moderate enantioselectivity.9 Although these reports have
advanced the state of the art, the development of new chiral
first-row transition metal catalysts to achieve an enantiocon-
vergent C(sp3)−C(sp2) coupling of more alkyl halides in a
highly enantioselective fashion is still highly desirable.
Owing to the low cost and toxicity of copper catalyst, we
surmised that it would be a potential first-row transition metal
catalyst for such a transformation.10 However, Liu and Fu have
disclosed copper-catalyzed racemic Suzuki−Miyaura coupling
of various alkyl halides via promiscuous mechanisms (either a
stereoablative radical process or a stereospecific SN2-type
pathway) with different stereochemical consequences (Scheme
1B).11 Thus, the reaction mechanism has to be to tuned
toward the radical process in order to achieve an
enantioconvergent transformation.11 To solve this challenge,
we speculated that a rational design of chiral ligands to
enhance the reducing capability of copper would be pivotal to
drive the reaction toward a radical process by favoring single-
electron reduciton of alkyl halides. As part of our continuous
INTRODUCTION
■
The Suzuki−Miyaura reaction is one of the most widely used
cross-coupling reactions for the construction of strategically
important C−C bonds owing to its broad reaction scope, as
well as the stability, availability, and low toxicity of organo-
boron reagents.1 Compared with the classic, powerful Suzuki−
Miyaura C(sp2)−C(sp2) coupling, the coupling of alkyl
(pseudo)halides with organoboron reagents to forge C(sp3)−
C(sp2) bonds has been less studied due to the relatively
difficult oxidative addition and the facile β-H elimination of
alkyl metal complexes.2 Particularly, the development of
catalytic asymmetric Suzuki−Miyaura C(sp3)−C(sp2) cou-
pling to access enantioenriched three-dimensional molecular
frameworks would further expand its exceptional capabilities in
organic synthesis.3 In this scenario, the stereoselective coupling
of enantioenriched alkyl electrophiles with organoboron
reagents using an achiral catalyst has evolved into a feasible
protocol to construct the chiral C(sp3)−C(sp2) bonds.4 In
comparison, the utility of chiral transition metal catalysis to
accomplish an enantioconvergent coupling of racemic alkyl
electrophiles represents a more appealing strategy due to its
chirality multiplication nature. In this regard, Fletcher and
Tang have independently developed the noble transition metal
(Rh, Pd) catalysis for the enantioconvergent coupling of
arylboronic acids with racemic cyclic allylic chlorides and α-
bromocarboxamides, respectively, through a dynamic kinetic
asymmetric transformation or resolution process.5 Recent
increased emphasis on sustainability and economy has shifted
the focus of catalysis from noble to first-row transition metals,
which could provide a suitable mechanism for stereo-
convergence by converting the racemic alkyl halides to
prochiral radical intermediates via a single electron reduction
process.6 In this context, the chiral nickel catalysis has been
Received: August 25, 2020
https://dx.doi.org/10.1021/jacs.0c09125
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© XXXX American Chemical Society
A

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a
Scheme 1. First-Row Transition Metal-Catalyzed
Enantioconvergent Suzuki−Miyaura C(sp3)−C(sp2)
Coupling
Table 1. Screening of Reaction Conditions
entry
2
[Cu]
CuI
L
solvent
DMSO
yield (%) ee (%)
0
b
1
2a
2a
2b
2c
2d
2e
2e
2e
2e
2e
2e
2e
2e
2e
2e
2e
2e
2b
L1
L1
L1
L1
L1
L1
L2
L3
L4
L5
L6
L4
L4
L4
L4
L4
L4
L4
2
3
4
5
6
7
8
9
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuI
CuTc
CuSCN
CuOAc
CuI
CuI
CuI
CuI
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
DMSO
39
51
0
31
31
0
55
86
41
51
56
47
36
19
17
80
58
18
16
31
28
87
89
85
60
87
89
87
94
91
91
87
interest in copper-catalyzed asymmetric radical reactions,12
herein we present a general enantioconvergent C(sp3)−C(sp2)
coupling of racemic alkyl halides with organoboronate reagents
catalyzed by Cu(I) 13 and a chiral electron-rich N,N,P-
ligand.12c,14 Notably, the reaction tolerates a number of aryl-
and heteroarylboronate esters as well as benzyl, heterobenzyl,
and propargyl bromides and chlorides, and these electrophiles
have been underrepresented in previously reported enantio-
convergent Suzuki−Miyaura reactions.5,7−9 Therefore, this
strategy (when combined with straightforward follow-up
manipulations) delivers a number of pharmaceutically useful
chiral 1,1-di(hetero)arylalkane and 1-aryl-1-heteroarylalkane
scaffolds15 as well as highly valuable synthons in organic
synthesis, such as chiral alkynes, alkenes, alcohols, and
carboxylic acids (Scheme 1C).
10
11
12
13
14
DMSO
c
15
DMSO/CH2Cl2
DMSO/DCE
DMSO/CH3CN
DMSO/CH2Cl2
c
16
17
c
c
18
a
Reaction conditions: ( )-1a (0.075 mmol), 2 (0.05 mmol), [Cu]
(10 mol %), L (12 mol %), LiOtBu (4.0 equiv), and H2O (2.0 equiv)
in solvent (0.60 mL) at room temperature for 24 h under argon. Yield
was based on H NMR analysis of the crude product using 1,3,5-
trimethoxybenzene as an internal standard. The ee values are based on
HPLC analysis. Without H2O. Solvent ratio (2:1), conducted at −5
°C for 48 h.
1
b
c
RESULTS AND DISCUSSION
■
Reaction Development. We initiated our study by
examining the cross-coupling between (1-bromoethyl)benzene
1a with arylboronate ester 2 with LiOtBu as the base, which is
beneficial for the transmetalation of organoboron reagents to
copper salt.11a Unfortunately, the initial attempts with various
arylboronate esters 2a−2e in the presence of CuI, ligand L1,
and LiOtBu in different solvents indicated very low reaction
efficiency at room temperature (Table 1, entry 1 and Table S1
in the Supporting Information). Water is reported to be helpful
to the Suzuki−Miyaura reaction due to its vital role in both
increasing the solubility of LiOtBu and promoting the
transmetalation step.16 Indeed, we found that the addition of
water greatly promoted the reaction efficiency and the desired
product 3 was generated in 39% yield with 31% ee (Table 1,
entries 1 and 2). The major side products were the
homocoupling product 3′ of boronate ester and ether 3″.
Since the choice of organoboron reagents is also crucial in the
transmetalation step and may ultimately influence the reaction
efficiency,1d we screened several organoboron reagents 2b−2e
and identified that the methylated acenaphthoquinone-derived
boronate (B(mac)) ester 2e17 gave the best yield (55%),
without affecting the ee value (Table 1, entry 6). The
subsequent ligand test revealed that our previously reported
3,5-di-tert-butyl-substituted N,N,P-ligand L213 for C(sp3)−
C(sp) coupling provided a slightly lower ee value, indicating
that further modification of ligands with different steric
properties at different positions was necessary (Table 1,
entry 7). We surmised that the ortho-substituted N,N,P-ligands
might increase the steric hindrance and be beneficial to the
enantioselectivity. Then, we synthesized a series of ortho-
substituted N,N,P-ligands L3−L6 (see Supporting Information
for their synthesis). The 2,4,6-trimethyl-substituted N,N,P-
ligand L3 indeed significantly enhanced the ee value to 87%,
B
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albeit in a lower yield (Table 1, entry 8). Ligand L4 with 2,6-
dimethyl substituents further enhanced the reaction efficiency
and enantioselectivity (Table 1, entry 9). The 1-naphthyl- and
9-phenanthryl-subsituted N,N,P-ligands (L5 and L6) did not
give better results than L4 (Table 1, entries 10 and 11). At last,
we identified that L4 was the best one, affording product 3
with 89% ee at ambient conditions. Further varying the copper
salts resulted in a decreasing yield of product 3 with almost a
similar ee (Table 1, entries 12−14). Lowering the temperature
to −5 °C by adding a cosolvent further increased the
enantioselectivity, and the mixed solvent of DMSO/CH2Cl2
significantly enhanced the reaction efficiency (Table 1, entries
15−17). A trial with the more readily available boronate ester
2b under the optimized conditions indicated a very low
conversion of 2b (Table 1, entry 18). We finally identified the
optimal conditions as follows: the reaction of 1a and 2e in a
molar ratio of 1.5:1.0 in the presence of 10 mol % of CuI, 12
mol % of L4, 4.0 equiv of LiOtBu, and 2.0 equiv of H2O in
DMSO/CH2Cl2 (v/v = 2:1) generated 3 in 80% yield with
94% ee (Table 1, entry 15). Replacing L4 with its
pseudoenantiomer L7 gave rise to the enantiomer of 3 (ent-
3) in 72% yield with 95% ee under otherwise identical
conditions.
Table 2. Scope for Synthesis of Enantioenriched 1,1-
Diarylalkanes
a
With the optimal reaction conditions in hand, we then
investigated the scope of benzyl bromides (Table 2).
Substrates with either electron-donating or electron-with-
drawing functional groups at the para or meta positions of
the phenyl rings reacted smoothly in comparable yields with up
to 97% ee (4−13). The substituents at the ortho positions of
the phenyl rings significantly affected the reaction efficiency:
the 2-fluoro-substituted product 14 was obtained in very low
yield, while other substrates with methyl or methoxyl groups at
the ortho positions did not give rise to the desired products.
Notably, the aryl−X (X = Cl, Br, I, F) bonds did not interfere
with the reaction and the desired products 8−11 were
efficiently generated. The naphthyl bromide was also a suitable
substrate for the coupling reaction to deliver the desired
product 15 with 91% ee, albeit with a low yield. In addition,
the simple linear benzyl bromides also worked well to provide
16−27 in moderate to good yields with 89−96% ee. A myriad
of functional groups, such as terminal olefin (23), ester (24),
nitrile (25), and acetal (26) at different distances away from
the reaction site were all compatible with the reaction
conditions. Furthermore, good chemoselectivity was observed
for the reaction of secondary benzylic bromide in preference to
the primary bromide (27). We next turned our attention to
examining the scope of arylboronate esters. The electron-
donating methoxyl group at the meta/para position was
tolerated to give rise to 28 and 29 in 55−62% yields with 94%
ee. The absolute configuration of 29 was determined to be R
by comparing its HPLC spectrum and optical rotation with
those reported in literature,18 and those of other products were
determined in reference to 29. Besides, the phenyl-substituted
arylboronates were also amenable to the coupling reaction to
afford 30 and 31 in excellent enantioselectivity. More
importantly, the electron-withdrawing functional groups
(carbonyl, cyano) at the meta/para position of arylboronates
were also suitable for the reaction to furnish the coupling
products 32−35 with 83−93% ee. Overall, by variation of
functional groups at either benzylic halides or B(mac)-derived
arylboronate esters, this strategy provided a wide range of
enantioenriched 1,1-diarylalkanes.15
a
Reaction conditions: ( )-1 (1.5 equiv), 2 (0.20 mmol), CuI (10 mol
%), L4 (12 mol %), LiOtBu (4.0 equiv), and H2O (2.0 equiv) in
DMSO/DCM (2:1, 2.4 mL) at −5 °C for 48 h under argon.
Heterocycles are prevalent in many pharmacologically
important core structures, and we envisioned that the
installation of various heterocycles into the enantioenriched
1,1-driarylalkane skeletons might be potentially useful for drug
discovery. Thus, we investigated the scope toward the
synthesis of enantioenriched 1-aryl-1-heteroarylalkanes and
1,1-diheteroarylalkanes from heterobenzyl bromides and
heteroarylboronate esters (Table 3). As such, alkyl bromides
bearing heteroarenes such as pyridine (36 and 37) and
quinoline (38) worked well to yield the enantioenriched 1-
aryl-1-heteroarylalkanes, and the quinoline-substituted product
was generated in a higher yield and enantioselectivity.
Similarly, the boronate esters containing different types of
electron-rich heteroarenes, such as the furan and thiophene,
coupled smoothly to provide 39 and 40 in good yields and
excellent enantioselectivity. The electron-withdrawing 2-
chloropyridylboronate ester was also suitable for the reaction
to provide 41 in good yield and enantioselectivity. Unfortu-
nately, no product was observed for the Bpin-derived pyridyl
boronate ester without substituents ortho to the nitrogen.
C
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Table 3. Scope for Synthesis of Enantioenriched 1-Aryl-1-
heteroarylalkanes and 1,1-Diheteroarylalkanes
Table 4. Scope for Synthesis of Enantioenriched
(Hetero)Benzyl Alkynes
a
a
a
Reaction conditions: ( )-1 (1.5 equiv), 2 (0.20 mmol), CuI (10 mol
%), L4 (12 mol %), LiOtBu (4.0 equiv), and H2O (2.0 equiv) in
b
DMSO/DCM (2:1, 2.4 mL) at −5 °C for 48 h under argon. At
c
room temperature for 24 h under argon. ( )-1 (1.0 equiv) for 72 h.
d
At −10 °C for 72 h.
a
Reaction conditions: ( )-1 (1.5 equiv), 2 (0.20 mmol), CuI (10 mol
%), L6 (12 mol %), LiOtBu (6.0 equiv), and H2O (3.0 equiv) in
DMSO/DCM (2:1, 2.4 mL) at −10 °C for 120 h under argon. For
72 h. For 96 h.
b
c
Noteworthy is that the coupling reaction between heterobenzyl
bromides and heteroarylboronate esters proceeded smoothly
as well to afford the enantioenriched 1,1-diheteroarylalkanes
42 and 43 with good enantioselectivity.
Synthetic Utility. The translation from small-scale to
preparative scale synthesis is a key step to transform the
reaction methodology to the industrial realm. To demonstrate
the preparative utility of our protocol, the enantioconvergent
Suzuki−Miyaura reaction was conducted on a gram scale,
providing the desired product 4 without a decrease in reaction
efficiency (Scheme 2A). Alkynes are one of the most important
and versatile synthetic intermediates in organic synthesis, and
to showcase the synthetic value of enantioenriched benzyl
alkynes, we carried out a myriad of transformations of our
coupled products to furnish other synthetically valuable
synthons (Scheme 2B). As such, alkyne 45 underwent the
oxidative cleavage of the triple bond smoothly to give rise to
the chiral benzyl carboxylic acid 53 in 89% yield, which was
smoothly converted to alcohol 54 via a sequential esterification
and LiAlH4 reduction in 93% yield with 94% ee. Upon
exposure to tetrabutylammonium fluoride (TBAF), the TIPS
group was easily removed to afford the terminal alkynes 55a
and 55b in high efficiency with 94% ee. Further, a partial
hydrogenation of chiral alkyne 55b afforded chiral terminal
alkene 56 in 92% yield with 95% ee. In addition, the complete
hydrogenation of 55b provided 57 with 90% ee, featuring a
saturated aliphatic chain. Most importantly, the structural
variations in the alkynyl moiety were also feasible. As shown in
Scheme 2B, the Sonogashira coupling between terminal alkyne
55a and different types of organohalides, such as aryl,
heteroaryl, and aliphatic halides, was successfully achieved to
generate diverse enantioenriched alkynes 58a−58c. Specifi-
cally, the coupling of 5-chloropyrazolo[1,5-a]pyrimidine with
55a afforded the product 58b, an analog of a patented mGluR
modulator,13 indicating its potential application in drug
Enantioenriched alkynes are found in not only natural
products and therapeutics, such as efavirenz and AMG 837, but
also highly valuable synthons in organic synthesis.19 Having
this in mind, we next switched our attention to the synthesis of
enantioenriched alkynes from the Suzuki−Miyaura coupling of
racemic propargyl bromides. However, the optimal conditions
for cross-coupling of benzyl halides were not suitable for the
reaction of propargyl bromides and only moderate reaction
efficiency and enantioselectivity were observed (Table S2 in
the Supporting Information). Upon systematic screening of
reaction parameters (Table S2), we found that the reaction of
the triisopropylsilyl (TIPS)-substituted propargyl bromide 1b
provided 44 with the best result in the presence of L6, with 6.0
equiv of LiOtBu and 3.0 equiv of water at −10 °C (Table S2,
entry 8). Under the optimal conditions, a number of racemic
propargyl bromides were amenable to the reaction to afford
enantioenriched alkynes 44−50 in moderate to good yields
with 84−94% ee (Table 4). Noteworthy is that many
functional groups at different positions away from the reaction
site of propargyl bromides were well tolerated, such as internal
alkene (46), chloride (47), and esters (48 and 49). The scope
was not limited to TIPS-substituted propargyl bromides, as can
be seen by the formation of 50. Other B(mac)-derived
boronate esters, containing different types of heterocycles such
as the 1,3-benzodioxole and pyridine, were also applicable to
the coupling reaction to deliver the desired products 51 and 52
with 80% and 90% ee, respectively. Notably, the substrates
were not limited to alkyl bromides and the less reactive
propargyl chloride 1c also underwent the desired reaction to
afford 45 in 42% yield with 95% ee.
D
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a
Scheme 2. Synthetic Applications
Scheme 3. Mechanistic Study
comparable yields (Scheme 3C and Scheme 3D), indicating
roughly the same reaction rates. Further, the enantiopurities of
the recovered 1a did not significantly change compared with
that of the starting materials in both of the two reactions
(slight racemization of 1a occurred under the reaction
conditions devoid of copper/chiral ligand, Scheme 3E).
Collectively, these results excluded a (dynamic) kinetic
resolution or dynamic kinetic asymmetric transformation
process.20
a
Reaction conditions: (a) RuCl3 (5 mol %) and NaIO4 in a mixed
solvent of CCl4/CH3CN/H2O (v/v/v = 2:2:3), rt, 4 h. (b) SOCl2,
MeOH, 0 °C to rt, 3 h; LiAlH4, THF, rt, 3 h. (c) TBAF in THF, rt, 1
h. (d) Pd/C (10 wt %) and H2 (1.0 atm) in THF, rt, 0.5 h. (e) Pd/C
(10 wt %) and H2 (1.0 atm) in THF, rt, 12 h. (f) For synthesis of 58a:
PhI, Pd(PPh3)4 (5 mol %), CuI (5 mol %) and Et3N in THF, 80 °C,
18 h. For synthesis of 58b: 5-chloropyrazolo[1,5-a]pyrimidine,
Pd(PPh3)4 (5 mol %), CuI (5 mol %) and KOAc in THF, rt, 18 h.
For synthesis of 58c: (3-bromopropyl)benzene, [(π-allyl)PdCl]2 (2.5
mol %), CuI (7.5 mol %), IPr·HCl (5 mol %) and Cs2CO3 in a mixed
solvent of DMF/Et2O (v/v = 1:2), 45 °C, 24 h. IPr·HCl = 1,3-
bis(2,6-diisopropylphenyl)imidazolinium chloride.
On the basis of these experiments and previous reports,11−13
we proposed a plausible mechanism as shown in Scheme 4. In
Scheme 4. Proposed Mechanism
discovery. Therefore, this strategy (when combined with
straightforward manipulations) delivers a number of highly
valuable synthons in organic synthesis.
Mechanistic Studies. To gain some insight into the
possible radical mechanism, we carried out some control
experiments. The reaction of radical clock substrate 59 with 1a
and 2ea led to the radical addition/ring-opening/arylation
product 60 in 6% yield along with the coupling product 33
under the standard reaction conditions (Scheme 3A). When
TEMPO was added under the otherwise standard conditions,
the reaction of 1a with 2e was completely inhibited and the
TEMPO-trapped product 61 could be detected by high
resolution mass spectroscopy (HRMS) (Scheme 3B). Similar
results were also observed for the corresponding control
experiments with propargyl bromide 1b (Scheme S1 in the
Supporting Information). These experiments implied the
involvement of a radical process in the reaction. In addition,
the reactions with either racemic or enantioenriched (1-
bromoethyl)benzene 1a afforded the desired products 3 in
the presence of base, CuI salt reacts with ligand L* to afford
the CuIL* complex, which further undergoes a transmetalation
process with B(mac)-derived arylboronate ester 2 and gives the
intermediate I. Afterward, this intermediate undergoes a single
electron reduction with alkyl bromide ( )-1 to concomitantly
deliver a prochiral alkyl radical II and the CuII complex III.
E
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The alkyl radical II might react efficiently with the complex III
to forge the chiral C(sp3)−C(sp2) bond and regenerate the
CuIL* complex for the next catalytic cycle.
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Notes
The authors declare no competing financial interest.
CONCLUSION
■
ACKNOWLEDGMENTS
We have established a general copper-catalyzed enantiocon-
vergent radical Suzuki−Miyaura C(sp3)−C(sp2) cross-cou-
pling of racemic alkyl halides with B(mac)-derived boronate
esters in high enantioselectivity. A multidentate cinchona
alkaloid-derived N,N,P-ligand is strategically utilized to
enhance the reducing capability of copper, thus providing a
ready mechanism for stereoconvergence by reducing the
racemic alkyl halides to the prochiral radical intermediate.
The copper/chiral N,N,P-ligand catalytic system is also crucial
in the enantiocontrol over the highly reactive radical species to
forge a chiral C(sp3)−C(sp2) bond. In addition, the reaction
features a broad substrate scope with high functional group
tolerance, covering aryl- and heteroarylboronate esters, as well
as benzyl, heterobenzyl, and propargyl halides. Therefore, this
method provides a valuable approach to a variety of potentially
useful chiral building blocks for organic synthesis and drug
discovery when allied with follow-up transformations. Further
expansion of the reaction scope and detailed mechanistic
studies are still in progress in our laboratory.
■
Financial support is from the National Natural Science
Foundation of China (Grants 21722203, 21831002, and
21801116), Guangdong Provincial Key Laboratory of Catalysis
(Grant 2020B121201002), Guangdong Innovative Program
(Grant 2019BT02Y335), Natural Science Foundation of
Guangdong Province (Grant 2018A030310083), Shenzhen
Special Funds (Grant JCYJ20180302180235837), and SUS-
Tech Special Fund for the Construction of High-Level
Universities (Grant G02216303). The authors acknowledge
the assistance of SUSTech Core Research Facilities. This paper
is dedicated to the 10th anniversary of Department of
Chemistry, SUSTech.
REFERENCES
■
(1) For selected recent reviews on Suzuki−Miyaura reaction, see the
following: (a) Beletskaya, I. P.; Alonso, F.; Tyurin, V. The Suzuki-
Miyaura Reaction after the Nobel Prize. Coord. Chem. Rev. 2019, 385,
137−173. (b) Biffis, A.; Centomo, P.; Del Zotto, A.; Zecca, M. Pd
Metal Catalysts for Cross-Couplings and Related Reactions in the
21st Century: A Critical Review. Chem. Rev. 2018, 118, 2249−2295.
(c) Johansson Seechurn, C. C. C.; Kitching, M. O.; Colacot, T. J.;
Snieckus, V. Palladium-Catalyzed Cross-Coupling: A Historical
Contextual Perspective to the 2010 Nobel Prize. Angew. Chem., Int.
Ed. 2012, 51, 5062−5085. (d) Partyka, D. V. Transmetalation of
Unsaturated Carbon Nucleophiles from Boron-Containing Species to
the Mid to Late d-Block Metals of Relevance to Catalytic C-X
Coupling Reactions (X = C, F, N, O, Pb, S, Se, Te). Chem. Rev. 2011,
111, 1529−1595.
ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/jacs.0c09125.
■
sı
Experimental procedures, characterization of com-
pounds, Tables S1 and S2, and Scheme S1 (PDF)
AUTHOR INFORMATION
Corresponding Authors
(2) For selected reviews on Suzuki−Miyaura coupling of alkyl
halides, see the following: (a) Yamamoto, A.; Nishimura, Y.;
Nishihara, Y. Recent Advances in Cross-Coupling Reactions with
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following:. (c) Ishiyama, T.; Abe, S.; Miyaura, N.; Suzuki, A.
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9-BBN Derivatives with Iodoalkanes Possessing β-Hydrogens. Chem.
■
Zhong-Liang Li − Academy for Advanced Interdisciplinary
Studies and Department of Chemistry, Southern University of
Science and Technology, Shenzhen 518055, China;
Email: lizl@sustech.edu.cn
Xin-Yuan Liu − Shenzhen Grubbs Institute and Department of
Chemistry, Guangdong Provincial Key Laboratory of Catalysis,
Southern University of Science and Technology, Shenzhen
518055, China; orcid.org/0000-0002-6978-6465;
Email: liuxy3@sustech.edu.cn
Lett. 1992, 21, 691−694. (d) Netherton, M. R.; Dai, C.; Neuschutz,
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K.; Fu, G. C. Room-Temperature Alkyl-Alkyl Suzuki Cross-Coupling
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Authors
Sheng-Peng Jiang − Shenzhen Grubbs Institute and Department
of Chemistry, Guangdong Provincial Key Laboratory of
Catalysis, Southern University of Science and Technology,
Shenzhen 518055, China
Xiao-Yang Dong − Shenzhen Grubbs Institute and Department
of Chemistry, Guangdong Provincial Key Laboratory of
Catalysis, Southern University of Science and Technology,
Shenzhen 518055, China; orcid.org/0000-0002-0663-
1482
Qiang-Shuai Gu − Academy for Advanced Interdisciplinary
Studies and Department of Chemistry, Southern University of
Science and Technology, Shenzhen 518055, China;
orcid.org/0000-0002-3840-425X
Liu Ye − Academy for Advanced Interdisciplinary Studies and
Department of Chemistry, Southern University of Science and
Technology, Shenzhen 518055, China
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Complete contact information is available at:
F
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