Pd-Catalyzed Site-Selective Borylation of Simple Arenes via Thianthrenation?

Article abstract of DOI:10.1002/cjoc.202000212

Site-selective borylation of simple arenes was realized in one pot via an electrophilic thianthrenation/Pd-catalyzed borylation sequence. The key to achieve this operatically simple process is the use of Pd catalysis, which could tolerate the solvent and acidic conditions used in the thianthrenation step. This protocol features mild conditions, broad functional group tolerance, and simple manipulations, and is suitable for late-stage functionalization of a wide range of pharmaceuticals and complex bioactive molecules.

Full text of DOI:10.1002/cjoc.202000212

Chinese Journal
of Chemistry
CJC
中 国 化 学 - An International Journal
Accepted Article
Title: Pd-Catalyzed Site-Selective Borylation of Simple Arenes via Thianthrenation
Authors: Xiao-Yue Chen, Yu-Hao Huang, Jian Zhou,* and Peng Wang*
This manuscript has been accepted and appears as an Accepted Article online.
This work may now be cited as: Chin. J. Chem. 2020, 38, 10.1002/cjoc.202000212.
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Chinese Journal
of Chemistry
Borylation, Arene, Site-Selective, Palladium, Sulfonium salts
Report
CJC
中
国 化 学 - An International Journal
Pd-Catalyzed Site-Selective Borylation of Simple Arenes via
Thianthrenation
Xiao-Yue Chen,a,b Yu-Hao Huang,b Jian Zhou,*a and Peng Wang*b,c
a Shanghai Key Laboratory of Green Chemistry and Chemical Process, East China Normal University, 3663N Zhongshan Road, Shanghai 200062, P. R. China
b State Key Laboratory of Organometallic Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, CAS 345 Lingling
Road, Shanghai 200032, China
c CAS Key Laboratory of Energy Regulation Materials, Shanghai Institute of Organic Chemistry, CAS 345 Lingling Road, Shanghai 200032, China
Cite this paper: Chin. J. Chem. 2019, 37, XXX—XXX. DOI: 10.1002/cjoc.201900XXX
Site-selective borylation of simple arenes was realized in one pot via an electrophilic thianthrenation/Pd-catalyzed borylation sequence. The key to achieve
this operatically simple process is the use of Pd catalysis which could tolerate the solvent and acidic conditions used in the thianthrenation step. This
protocol features mild conditions, broad functional group tolerance, and simple manipulations, and is suitable for late-stage functionalization of a wide
range of pharmaceuticals and complex bioactive molecules.
sulfonium salts formation step. Herein, we reported a simplified
procedure for site-selective borylation of simple arene using this
Background and Originality Content
Site-selective functionalization of undirected simple arenes
mediator approach (Scheme 1b), and the full scope of various
remains a great challenge in synthetic community due to the subtle
monosubstituted and multisubstituted simple arenes were
differences of several reactive sites regarding the electronic and
evaluated. The key to achieve this operatically simple process is the
steric properties in the same molecule.1,2 Previously, site-
use of a Pd/phosphine catalyst which could tolerate the solvent and
selectivity has been obtained using electron rich anisole, aniline or
wastes in the thianthrenation step. In addition, a suitable base is
heteroarenes in electrophilic aromatic substitution reaction3. By
also crucial to alter the pH value of the reaction system. This
adopting sterically guided transition metal catalysts, excellent site-
reaction features mild conditions, broader functional group
selectivity was realized when concerning 1,2- and 1,3-disubstituted
tolerance, and simple manipulations in comparison to our previous
simple arenes.4 More recently, both covalent and noncovalent
photoredox process, thus makes it high value for late-stage
directing group approaches for transition metal catalysis allow the
functionalization of pharmaceuticals and bioactive complex
site-selective functionalization of aromatics with polar functional
molecules.
group assistance.5,6 However, limited success on site-selective
Scheme
1
Site-selective borylation via thianthrenation/Pd-catalyzed
functionalization of simple arenes, especially monosubstituted
electron-neutral and electron-deficient arenes, has been reported.
Recently, Ritter group has demonstrated a series of late-stage
functionalization of arenes via the isolated aryl thianthrenium salts,
in which remarkable site-selectivity was obtained.7-9 Almost at the
same timeline, we were developing a transient mediator approach
for para-selective functionalization of monosubstituted simple
arenes, and found thianthrene S-oxide (TTSO) and phenoxathiine
10-oxide could serve as the most selective and efficient mediators
via sulfide dication intermediates (Scheme 1a).10a Ideally, this
approach could provide a powerful alternative strategy providing a
remarkable selectivity for a wide range of aromatics. However, this
approach suffers from multiple manipulations requiring the
isolation of sulfonium salts or removal of the solvent and acid in the
first step. For example, our previous photoredox process cannot
tolerate with the solvent, acidic conditions used in the first
desulfurative borylation
arenes
TTSO mediated
of monosubstituted
via
catalysis
photoredox
para
(a)
-borylation
R
R
(BPin)2
Photoredox Catalysis
Thianthrenation
via sulfide dication
OTf
R
S
S
H
BPin
or removal
and
solvent
isolation
of acid
♦
narrow
scope
substrate
extra
operationally manupulations
work:
arenes
via Pd catalysis
This
TTSO mediated site-selective
of
simple
(b)
borylation
via
Tf
DCM, -40 o
C
to
2O,
,
rt
TTSO
1)
OTf
S
BPin
H
Ar
Ar
Ar
S
/XPhos,
CCO Na,
2
(BPin)2
2) Pd(OAc)2
(CH3)3
removal
and
of acid
without
solvent
♦
♦
broad
♦
one
scope
mild conditions
pot
simple manupulation
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10.1002/cjoc.202000212
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First author et al.
Report
Table 2 Para-borylation of monosubstituted arenes.a,b
Results and Discussion
R
Organoborons are appealing synthetic linchpin which are
widely used in organic synthesis, and pharmaceutical industry.11 As
such, development of efficient site-selective borylation of
undirected arenes are desired. Inspired by our recently TTSO
mediated para-arylation and alkenylation reaction of
monosubstituted arenes with Pd catalyst,10b we hypothesized that
the TTSO-mediated site-selective borylation of simple arene could
be realized with one synthetic operation via a thianthrenation/Pd-
O
S
R
, ,
TTSO Tf2O DCM
1
)
-
.
40 oC t
t
1 5 h
,
o r
,
n
t
OPi
c
)
os
2
Bpi
Pd OA 2/XPh
) (
)
(
2
S
,
ce one
A
N
/
C
D M
1 1 N2
/
(
)
n
Bpi
2
,
,
H
1
TT
SO
a
v
r
t
12 h
c
OA
R
e
Ph
O
OM
=
,
,
,
a
2
2b
e
M
R
95
%
Et
7
90
9
%
%
t
u
B
c
2
,
,
2d
Cy
82%
n
n
n
B
e
2
B i
n
p
Bpi
n
Bpi
84%
12 di
8
2
%
Bpi
Table 1 Evaluation of reaction parameters.a,b
,
,
,
mono
2f
7
9%
2g
2h
90%
(
)
',
2h
O
N
%
(
)
O
S
Me
Me
Me
TTSO Tf
,
DCM
2O,
1)
c
OA
-40 oC to rt, 1.5 h
O
OC
F H
N
F
+
2
,
/XPhos
S
2) (Bpin)2 Pd(OAc)2
DCM/solvent
Base, rt, 12 h
v/v
N
),
2
1,
(1/
H
p-Tol
TTSO
Bpin
2a
1a
3
n
n
n
n
n
4
sources
Bpi
,
Bpi
Bpi
,
Bpi
,
Bpi
Entry
Solvent
MeOH
DMF
Base
K3PO4
K3PO4
Yield
of 2a/3 Entry
Pd
Yield
(%)
(%)
,
,
m
2
c
52%c
5
Pd(PtBu3
catalysis
catalysis
2i
2
2k
59
%
44
%
72
%
2l
1
2
80/10
54/4
7
8
70
%
as
as
j
)
2
69
Pd(dppf)Cl2
NPhth
e
CO2M
NPhth
3
4
Acetone
Acetone
K3PO4
K2CO3
92/4
83/3
9
PPh3 instead of XPhos
BINAP instead of XPhos
81
85
NPhth
C
l
10
5
Acetone
KOPiv
93/3
11
12
BrettPhos instead of XPhos
64
96
99
c/-
6
Acetone
NaOPiv
instead XPhos
SPhos
of
n
Bpi
n
n
n
Bpi
n
Bpi
,
r
2
66%
(95)
Bpi
o
Bpi
,
,
c
,
,
n
2
2
2p
2q
44
%
61
%
91%
66%
MeO
iPr
OMe
NPhth
iPr
PPh2
PPh2
PPh2
MeO
e
M
e
CO2
M
PCy2
iPr
PCy2
iPr
CO2
H
Fe
e
CO2M
PCy2
OMe
e
CO2M
e
OM
PPh2
iPr
iPr
XPhos
BINAP
BrettPhos
SPhos
dppf
aReaction conditions: 1) toluene (0.2 mmol), TTSO (0.24 mmol), Tf2O (0.24
mmol), DCM (1.0 mL), N2; -40 oC for 30 min, then rt for another 1 h; 2) [Pd]
(5.0 mol %), Ligand (5.0 mol %), (Bpin)2 (2.0 equiv), base (3.0 equiv), solvent
(1.0 mL). bThe yield was determined by 1H NMR using CH2Br2 as the internal
standard; only para-borylated product was observed. cIsolated yield.
n
n
n
Bpi
,
w
2
43
Bpi
Bpi
,
n
n
Bpi
,
Bpi
s
,
60%c
53
%
52
%
%
,
,
c
c
c
d
u
v
2
2t
2
2
89%
r
B
O
O
N
O
O
O
c
,
A
r
B
n
Bpi
,
,
,
aa
62
n
Bpi
n
Bpi
n
Bpi
2
x
2
z
2y
2
42
%
58
%
89
%
%
aReaction conditions: 1) 1 (0.2 mmol), Thianthrene S-oxide (0.24 mmol),
o
Tf2O (0.24 mmol), DCM (1.0 mL), N2; -40 C for 30 min, then rt for 1 h; 2)
Pd(OAc)2 (5.0 mol %), XPhos (5.0 mol %), (Bpin)2 (2.0 equiv), NaOPiv (3.0
equiv), Acetone (1.0 mL); Only para-borylation products were observed in
1
b
c
d
crude H NMR. Isolated yield. DCM (0.2 mL) was used. Pd(OAc)2 (10
mol %), XPhos (10 mol %) were used.
catalyzed desulfurative borylation sequence. We are glad to find
that the Pd-catalyzed borylation reaction showed superior
compatibility with the conditions used in the first sulfonium salts
formation step. The desired para-borylated toluene could be
obtained in 95% isolated yield in the presence of Pd(OAc)2 (5.0
mol%), XPhos (5.0 mol%), sodium pivalate (3.0 equiv) in
DCM/acetone (1/1, v/v) after systematically evaluation of the
solvents and bases (entries 1-6). The use of sodium pivalate is
crucial for this one-pot reaction, which could inhibit the formation
of a dimerization byproduct. Based on our previous para-arylation
with arylborons, we hypothesized that the biaryl byproduct
derived from the coupling of the sulfonium salts intermediate with
the arylboron product. A series of phosphine ligands (entries 7-12)
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Chin. J. Chem. 2019, 37, XXX－XXX
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Running title
Chin. J. Chem.
were also investigated, in which SPhos gave similar activity with
XPhos albeit the others all led to inferior yields.
electrophilic properties of the thianthrenium dication intermediate.
A wide range of disubstituted arenes (4a-g) and trisubstituted
arene (4h) are suitable substrates for this TTSO-mediated
borylation protocol. Notably, the electron-rich heterocycles
including indoline (4i), 1,2,3,4-tetrahydroquinoline (4j), 1,2,3,4-
tetrahydroquinolin-2-one (4k), and carbazole (4l) are also suitable
substrates for this reaction, selectively delivering the boron group
to the para-position to the nitrogen on those heterocycles.
Due to the remarkable site-selectivity and versatility of
arylborons as a synthetic linchpin, the TTSO-mediated site-
selective borylation represents a charming process for late-stage
functionalization of drugs and complex bioactive molecules. With
our newly developed one-pot process, site-selective borylation of
pharmaceuticals, Pyriproxyfen (6a), Nimesulide (6b), Flurbiprofen
(6c), Biscalid (6d), and Isoxepac methyl ester (6e) were
demonstrated.
With the optimal conditions in hand, monosubstituted arenes
were firstly evaluated. As summarized in Table 2, all substrates
listed in the table gave excellent positional selectivities, and only
para-borylated products were observed in crude 1H NMR.
Moreover, this newly developed protocol typically provided
broader substrates scope in comparison with the photoredox
catalysis. For instance, the Ac-protected benzyl alcohol (1m), Phth-
protected benzyl amine (1n), Phth-protected phenethylamine (1o),
Phth-protected 3-phenyl-1-propanamine (1p), native 2-
phenylpropionic acid (1u) and amino acid derivative (1w) resulted
in very low yields, and the dehalogenation happened for 1-chloro-
3-phenylpropane (1q) under the previous photoredox conditions.
Not surprisingly, alkylated benzene derivatives (1a-e), anisole (1f),
Ac-protected phenol (1g), phenyl ether (1h), aniline derivatives (1j-
k) were all compatible with this one-pot procedure, giving the
desired arylborons in moderate to high yields. Fluorobenzene (1l)
provided the para-borylated product in 52% yield. Other functional
groups on alkyl chain did not significantly affect the efficiency of
this process, like ester (2r, 2t, 2v), ether (2s), masked amino alcohol
(2x), and epoxide (2y). Substituted phenyl ether (1z) and biphenyl
(1aa) were also tolerated under current conditions, yielding the
targeted products in 89% and 62% yields, respectively. Electron-
deficient arenes and electron-deficient heterocycles are
incompatible with this protocol probably due to the electrophilic
properties of the sulfide dication intermediate in the
thianthrenation step.
Table 4 Late-stage functionalization of bioactive scaffolds.a,b
O
S
, ,
TTSO Tf2O DCM
1
)
-
.
40 oC t t 1 5 h
,
o r
r
A
n
Bpi
r
A
H
,
n
t
c
os
Pd OA 2/XPh
2
Bpi
) (
)
(
)
2
S
,
ce one
A
/DCM 1/1 N2
(
)
, ,
v r
6
7
TTSO
a
N OPi t 12 h
e
M
s
e
M
NHM
O
CO2H
N
O
O
n
Bpi
O
n
Bpi
F
NO2
n
Bpi
r
7
rox en
mesu
Ni
7b
e
ur ro en
Py ip
yf
lid
Fl bip
7
f
,
c
,
,
c
61
d
a
50
90
%
%
%
Table 3 Site-selective borylation of multi-substituted arenes.a,b
n
Bpi
e
O
CO2M
O
O
TTSO Tf
DCM
,
2O,
,
1)
n
Bpi
S
-40 oC to rt, N2 1.5 h
N
H
Ar
5
Ar
H
Bpin
N
C
l
/XPhos
,
2) (Bpin)2 Pd(OAc)2
DCM/Acetone
O
S
v/v
1,
(1/
)
sca
Bi
r
m
7
soxe ac
%
o
lid
%
I
p
f
4
TTSO
rt, 12 h
NaOPiv, N2
,
,
,
49
e
7d
53
Cl
Me
Ac
Bpin
Bpin
Bpin
Bpin
O
O
aReaction conditions: 1) 6 (0.2 mmol), Thianthrene S-oxide (0.24 mmol),
Tf2O (0.24 mmol), DCM (1.0 mL), N2; -40 C for 30 min, then rt for 1 h; 2)
o
Me
OH
5a
5b
5c
5d
56%
,
91%
72%
83%
75%
69%
63%
,
,
,
,
Pd(OAc)2 (5.0 mol %), XPhos (5.0 mol %), (Bpin)2 (2.0 equiv), NaOPiv (3.0
b
c
Me
equiv), Acetone (1.0 mL). Isolated yield. Pd(OAc)2 (10 mol %), XPhos (10
CO2Et
OMe
Bpin
Bpin
Me
Bpin
Ac
NO2
mol %) were used. dDCM (0.2 mL) was used.
Bpin
Me
OMe
OMe
5e
5f
5g
5h 77%
,
,
,
The scalability of this process was demonstrated by the
borylation of 3,4-dihydro-2(1H)-quinolinone (4k) on 7.0 mmol scale,
and 78% yield of targeted arylboron was obtained. Most
importantly, the mediator thianthrene S-oxide (TTSO) could be
recycled in 86% total yield upon the oxidation of recovered
thianthrene (Scheme 2). In addition, drug molecule Vesnarinone
could be obtained in one step employing borylated 3,4-dihydro-
2(1H)-quinolinone as starting material. .
Bpin
Bpin
Bpin
Bpin
N
N
N
O
N
H
Ts
Ts
Ts
60%
73%
90%c
60%
,
5i
5j
5k
5l
,
,
,
a Reaction conditions: 1) 2 (0.2 mmol), Thianthrene S-oxide (0.24 mmol),
Tf2O (0.24 mmol), DCM (1.0 mL), N2; -40 C for 30 min, then rt for 1 h; 2)
o
Pd(OAc)2 (5.0 mol %), XPhos (5.0 mol %), (Bpin)2 (2.0 equiv), NaOPiv (3.0
b
equiv), Acetone (1.0 mL). Isolated yield. cPd(OAc)2 (10 mol %), XPhos (10
mol %) were used.
Next, we turned our attention to explore the scope of the
multisubstituted arenes. Typically, the boron group was installed
to the most electron rich sites in the arenes due to the highly
Chin. J. Chem. 2019, 37, XXX－XXX
© 2019 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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This article is protected by copyright. All rights reserved.

First author et al.
Report
Scheme 2 Gram-scale reaction and synthetic application
Glorius, F. Beyond Directing Groups: Transition-Metal-Catalyzed C-H
Activation of Simple Arenes. Angew. Chem. Int. Ed. 2012, 51,
10236−10254; (b) Hartwig, J. F.; Larsen, M. A. Undirected,
Homogeneous C−H Bond Functionalization: Challenges and
Opportunities. ACS Cent. Sci. 2016, 2, 281−292; (c) Wedi, P.; van
Gemmeren, M. Arene-Limited Nondirected C-H Activation of Arenes.
Angew. Chem. Int. Ed. 2018, 57, 13016−13027.
O
S
TTSO Tf
DCM
,
2O,
1)
H
Bpin
-40 oC to rt, 1 h
/XPhos
,
2) (Bpin)2 Pd(OAc)2
N
H
O
N
H
O
S
Acetone/DCM
NaOPiv,
1
N
(1/ ),
2
TTSO
86%)
rt, 12 h
g,
(1.68
4k,
5k
,
1.03 g
78%
O
MeO
MeO
For recently selected examples on the undirected C−H
functionalization of simple arenes, see: (a) Liu, W.; Cao, H.; Zhang, H.;
Zhang, H.; Chung, K. H.; He, C.; Wang, H.; Kwong, F. Y.; Lei, A.
Organocatalysis in Cross-Coupling: DMEDA-Catalyzed Direct C-H
Arylation of Unactivated Benzene. J. Am. Chem. Soc. 2010, 132,
16737−16740; (b) Shirakawa, E.; Itoh, K.-I.; Higashino, T.; Hayashi, T.
tert-Butoxide-Mediated Arylation of Benzene with Aryl Halides in the
Presence of a Catalytic 1,10-Phenanthroline Derivative. J. Am. Chem.
Soc. 2010, 132, 15537−15539; (c) Sun, C.-L.; Li, H.; Yu, D.-G.; Yu, M.;
Zhou, X.; Lu, X.-Y.; Huang, K.; Zheng, S.-F.; Li, B.-J.; Shi, Z.-J. An Efficient
Organocatalytic Method for Constructing Biaryls through Aromatic C-
H Activation. Nat. Chem. 2010, 2, 1044−1049; (c) Guo, X.; Li, C.-J.
Ruthenium-Catalyzed Para-Selective Oxidative Cross-Coupling of
Arenes and Cycloalkanes. Org. Lett. 2011, 13, 4977–4979; (d) Wang,
X.; Leow, D.; Yu, J.-Q. Pd(II)-Catalyzed para-Selective C–H Arylation of
mono-Substituted Arenes. J. Am. Chem. Soc. 2011, 133, 13864–13867;
(e) Romero, N. A.; Margery, K. A.; Tay, N. E.; Nicewicz, D. A. Site-
Selective Arene C–H Amination via Photoredox Catalysis. Science 2015,
349, 1326−1330; (f) Boursalian, G. B.; Ham, W. S.; Mazzotti, A. R.;
Ritter, T. Charge-transfer-directed radical substitution enables para-
selective C–H functionalization. Nat. Chem. 2016, 8, 810–815; (g)
Wang, P.; Verma, P.; Xia, G.; Shi, J.; Qiao, J. X.; Tao, S.; Cheng, P. T. W.;
Poss, M. A.; Farmer, M. E.; Yeung, K.-S.; Yu, J.-Q. Ligand-Accelerated
Non-Directed C-H Functionalization of Arenes. Nature 2017, 551,
489−493; (h) Luan, Y.-X.; Zhang, T.; Yao, W.-W.; Lu, K.; Kong, L.-Y.; Lin,
Y.-T.; Ye, M. Amide-Ligand-Controlled Highly para-Selective Arylation
of Monosubstituted Simple Arenes with Arylboronic Acids. J. Am.
Chem. Soc. 2017, 139, 1786−1789; (i) Chen, H.; Wedi, P.; Meyer, T.;
Tavakoli, G.; van Gemmeren, M. Dual Ligand-Enabled Nondirected C-
H Olefination of Arenes. Angew. Chem., Int. Ed. 2018, 57, 2497−2501;
(j) Chen, X.-Y.; Wu, Y.; Zhou, J.; Wang, P.; Yu, J.-Q. Synthesis of beta-
Arylethenesulfonyl Fluoride via Pd-Catalyzed Nondirected C-H
Alkenylation. Org. Lett. 2019, 21, 1426–1429; (k) Ruffoni, A.; Juliá, F.;
Svejstrup, T. D.; McMillan, A. J.; Douglas, J. J.; Leonori, D. Practical and
Regioselective Amination of Arenes Using Alkyl Amines. Nat. Chem.
2019, 11, 426–433.
O
N
MeO
NH
Bpin
N
N
,
MeO
Cu(OAc)2 B(OH)3
N
O
MS, MeCN, 80 o Air
H
5k
Vesnarinone
74%
4Å
C,
N
H
O
yield
Conclusions
In summary, thianthrene S-oxide mediated selective C-H
borylation of a wide range of arenes has been demonstrated via Pd
catalyzed desulfurative borylation reaction. This synthetically
simple one-pot process is highly useful for the late-stage
functionalization of bioactive molecules and for the synthesis of
bioactive compounds.
Experimental
General procedure for site-selective borylation: A 10 mL
Schlenk tube was charged with thianthrene S-oxide (55.7 mg, 0.24
mmol, 1.2 equiv.), CH2Cl2 (1.0 mL) and 1a (0.2 mmol, 1.0 equiv.)
under a nitrogen atmosphere. The suspension was then cooled to
-40 °C, followed by the dropwise addition of Tf2O (44 μL, 0.24 mmol,
1.2 equiv.). The resulting blue mixture was stirred at -40 °C for 30
min, and was allowed to stir at room temperature for another 1
hour. Then, bis(pinacolato)diboron (0.4 mmol, 2.0 equiv), Pd(OAc)2
(2.4 mg, 5.0 mol%), XPhos (4.8 mg, 5.0 mol%), sodium pivalate
(74.5 mg, 0.6 mmol, 3.0 equiv) were added under a nitrogen
atmosphere, followed by the addition of acetone (1.0 mL). The
reaction mixture was stirred at room temperature for 12 hours.
Subsequently, the mixture was passed through a pad of Celite with
DCM as the eluent to remove the insoluble precipitate. The
resulting solution was concentrated and purified by preparative
thin-layer chromatography to afford the desired product 2a.
Supporting Information
The supporting information for this article is available on the
WWW under https://doi.org/10.1002/cjoc.2018xxxxx.
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Acknowledgement
We gratefully acknowledge Shanghai Institute of Organic
Chemistry, State Key Laboratory of Organometallic Chemistry,
National Natural Science Foundation of China (21821002) for
financial support.
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© 2019 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2019, 37, XXX－XXX
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(The following will be filled in by the editorial staff)
Manuscript received: XXXX, 2019
Manuscript revised: XXXX, 2019
Manuscript accepted: XXXX, 2019
Accepted manuscript online: XXXX, 2019
Version of record online: XXXX, 2019
Chin. J. Chem. 2019, 37, XXX－XXX
© 2019 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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First author et al.
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Entry for the Table of Contents
Page No.
Pd-Catalyzed Site-Selective Borylation of Simple
Arenes via Thianthrenation
Me
Me
O
S
,
N
O
N
O
O
TTSO
1)
Tf
DCM
2O,
H
O
O
Bpin
/XPhos
(BPin)2
2) Pd(OAc)2
NaOPiv,
S
TTSO
O
removal
and
solvent
without
of acid
pot
Pyriproxyfen
♦
♦
♦
one
scope
mild conditions
broad
simple manupulation
Site-selective borylation of simple arenes was realized in one pot via an electrophilic
thianthrenation/Pd-catalyzed borylation sequence. This protocol features mild conditions, broad
functional group tolerance, and simple manipulations, and is suitable for late-stage functionalization
of a wide range of pharmaceuticals and complex bioactive molecules.
Xiao-Yue Cheng, Yu-Hao Huang, Jian Zhou,* Peng
Wang*
www.cjc.wiley-vch.de
© 2019 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Chin. J. Chem. 2019, 37, XXX－XXX
This article is protected by copyright. All rights reserved.