Multiple Electrophilic C-H Borylation of Arenes Using Boron Triiodide

Article abstract of DOI:10.1021/acs.orglett.9b04483

Electrophilic C-H borylation of arenes using boron triiodide has been developed. This reaction proceeded smoothly in the absence of additives, and the diiodoboryl group was installed at the most sterically accessible carbon, where the HOMO is localized to a certain extent. Moreover, regioselective multiple borylation of polycyclic aromatic compounds was achieved by using excess boron triiodide. The borylated intermediates were transformed into a variety of arylboron compounds such as arylboronates, boronic acids, and trifluoroborates.

Full text of DOI:10.1021/acs.orglett.9b04483

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Letter
Multiple Electrophilic C−H Borylation of Arenes Using Boron
Triiodide
Susumu Oda, Kenta Ueura, Bungo Kawakami, and Takuji Hatakeyama*
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ABSTRACT: Electrophilic C−H borylation of arenes using boron
triiodide has been developed. This reaction proceeded smoothly in
the absence of additives, and the diiodoboryl group was installed at
the most sterically accessible carbon, where the HOMO is localized
to a certain extent. Moreover, regioselective multiple borylation of
polycyclic aromatic compounds was achieved by using excess
boron triiodide. The borylated intermediates were transformed
into a variety of arylboron compounds such as arylboronates,
boronic acids, and trifluoroborates.
rylboron compounds not only have been used as useful
demonstrate electrophilic C−H borylation of arenes by
employing BI3 in the absence of precious metal catalysts and
additives. This simple system is applicable to the preparation of
arylboronic acids, boronates, and trifluoroborates; construction
of phenoxaborin and phenazaborin structures; and regiose-
lective multiple borylation of polycyclic aromatic com-
pounds,15 which have not been achieved using electrophilic
protocols.9−13
We began our study by investigating the electrophilic C−H
borylation with tetralin 1a, and Table 1 summarizes the
optimization results. In the presence of 1.0 equiv of BI3, 1a was
stirred at 120 °C for 16 h under neat conditions. After removal
of the generated HI in vacuo, successive addition of
triethylamine and pinacol provided the arylboronic acid
pinacol ester 2a in 78% yield (entry 1). Notably, selective
borylation occurred at the 2-position and no regioisomer was
obtained. After further screening of the reaction temperature,
the yield was improved to be 94% by carrying out the reaction
at 160 °C (entry 3). The reaction also proceeded with the use
of a reduced amount of 1a (5.0 equiv) and gave the product in
82% yield (entry 5).
A
synthetic intermediates,1 but also have attracted consid-
erable attention as functional materials.2−5 For example,
arylboronic acids participate in reversible Lewis pairing,
boroxine formation, and esterification with diols to serve as
catalysts,2 medicines,3 sensors,4 and building blocks for
covalent porous materials.5 Over the past decade, transition
metal-catalyzed direct C−H borylation has offered a
straightforward approach for the synthesis of arylboronates.6−8
However, these methods typically require precious-metal-based
catalysts such as iridium-,7a,b rhodium-,7c−e and platinum-based
catalysts,7f−h which are not suitable for industrial applications,
while several non-noble transition metal-based catalysts have
also been used for catalytic C−H borylation.8
Electrophilic C−H borylation is a transition metal-free
approach for the synthesis of arylboron compounds.9−13 Since
the pioneering contributions by Hurd, Muetterties, and
Lappert et al.,10 significant progress has been achieved by
Vedejs and co-workers11 and Ingleson and co-workers12
toward establishing efficient arene borylation methods, which
are complementary to the transition metal-catalyzed ones in
terms of regioselectivity. However, these approaches require
stoichiometric amounts of Lewis acids and do not allow for
multiple borylations. Although several groups have reported
electrophilic C−H borylation methodologies using catalytic
activators11b,12a,13h,l,o or directing groups,12i,13r the develop-
ment of additive-free borylation processes with a broad
substrate scope is highly desirable. Recently, we reported the
syntheses of BN-doped aromatic compounds, which showed
high performance as luminescent materials for organic light-
emitting diodes, via tandem electrophilic C−H borylation.14
As part of our continued effort toward the development of
novel methodologies for electrophilic C−H borylation, we
found that boron triiodide (BI3) is an effective reagent for the
borylation of electron-rich triarylamines.14b Herein, we aim to
As shown in Scheme 1, treatment of the borylated
intermediate with water afforded the corresponding boronic
acid 3 in 89% yield. The intermediate was also successfully
converted to potassium trifluoroborate 4 in 86% yield by using
potassium fluoride. Thus, this method enabled the facile
transformation of the borylated intermediate to arylboronic
acids and borates, which were not obtained by reported
Received: December 14, 2019
https://dx.doi.org/10.1021/acs.orglett.9b04483
© XXXX American Chemical Society
Org. Lett. XXXX, XXX, XXX−XXX
A

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Letter
Table 1. Electrophilic C−H Borylation of Tetralin
Scheme 2. Substrate Scope for Electrophilic C−H
ab
Borylation
a
b
entry
temp
yield
78%
84%
1
2
3
4
120 °C
140 °C
160 °C
180 °C
160 °C
94% (84%)
80%
c
5
82%
a
Reaction conditions: tetralin (1a) (15 mmol), BI3 (1.0 mmol) at
b
120−180 °C for 16 h under nitrogen atmosphere. Yields were
determined by 1H NMR using 1,1,2,2-tetrachloroethane as an internal
c
standard, and isolated yields are shown in parentheses. 5.0 equiv of
1a (5.0 mmol) was used.
a
Scheme 1. Synthesis of Boronic Acid and Trifluoroborate
a
1
Yields were determined by H NMR using dibromomethane as an
internal standard, and isolated yields are shown in parentheses.
a
Reaction conditions: arene (1) (0.8 mmol), BI3 (0.2 mmol), 1,2,4-
trichlorobenzene (1.6 mL) at 180 °C for 2−16 h under nitrogen
b
atmosphere. Yields were determined by 1H NMR using 1,1,2,2-
methods, because the use of a stoichiometric amount of
additives may hamper the transformation.12e
tetrachloroethane as an internal standard, and isolated yields are
c
shown in parentheses. Reaction of arene (1) (15 mmol) with BI3
Having established conditions for the metal-free borylation,
we evaluated the scope of the arene substrates, which are
summarized in Scheme 2. First, 3-chloro-o-xylene 1b was
evaluated, and it underwent selective borylation at the 5-
position to afford 2b in 76% yield.16 Unfortunately, the
borylation of other chloro-substituted substrates such as
chlorobenzene and 1,2-dichlorobenzene resulted in low yield
due to its low reactivity and the reaction of 3-chloro-o-xylene
only provided a satisfying yield so far. The borylation of
naphthalene proceeded selectively at the 2-position and
furnished 2c in 62% yield.17 Similarly, anthracene, tripheny-
lene, pyrene, and perylene were also compatible with the
reaction conditions and afforded the corresponding 2-
borylated products (2d, e, h−j). The excess substrates mostly
remained intact and were recovered.18 In contrast, borylation
of phenanthrene and fluorene resulted in a mixture of
regioisomers, wherein the boron atoms were substituted at
the 2- and 3-positions in 51:49 and 63:37 ratios, respectively
(2f, g). Diphenyl ether and N-phenyl carbazole participated in
C−H borylation and gave comparable yields with higher
regioselectivity (2k, l). Notably, the borylation of ferrocene
proceeded smoothly at 0 °C and furnished 2m in 70% yield. In
particular, the regioselectivity did not depend on the reaction
time in all the cases.
(1.0 mmol) was conducted at 160 °C for 16 h under neat conditions.
d
e
Reaction was conducted at 160 °C for 8 h. 2.0 equiv of arene (1)
f
g
was used. Reaction was conducted at 200 °C for 8 h. Reaction was
conducted in 1,2-dichlorobenzene at 0 °C for 12 h.
were performed at the B3LYP/6-31G(d) level of theory.
Although the highest occupied molecular orbital (HOMO) of
3-chloro-o-xylene was localized on the carbon at the 6-position
(indicated by the red circle), borylation took place at the 5-
position (Figure 1). Given that 1b-5-BI2 is more stable than
the other regioisomers by 5.1 kcal/mol, the observed
regioselectivity cannot be explained by the electron density
of HOMO but can be accounted for by considering the
stability of the borylated product. However, in the case of
diphenyl ether, 1k-3-BI2 and 1k-4-BI2 were formed in a 25:75
ratio. This value was inconsistent with the theoretically
predicted ratio of 7:93, which was determined by their energy
difference of 2.3 kcal/mol. These results indicated that this
reaction is kinetically controlled due to the steric bulkiness of
BI3, which led to predominant borylation at the less hindered
carbon. Furthermore, the DFT calculations for 9,10-
diphenylanthracene showed that the HOMO is mainly
localized on the anthracene skeleton and does not exist on
the phenyl substituents. Although 1e-9b-BI2 is the most stable
borylated intermediate and the m-carbon of the phenyl group
is sterically less congested, the 2-borylated product was
obtained selectively. This result suggested the borylation
To gain insight into the regioselectivity observed in this
transformation, density functional theory (DFT) calculations
for 3-chloro-o-xylene 1b, diphenyl ether 1k, 9,10-diphenylan-
thracene 1e, and the corresponding borylated intermediates
B
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the addition of mesitylmagnesium bromide, which afforded
phenoxaborin analogue 5 in 87% yield. In contrast to the case
of the diphenyl ether, borylation took place selectively at the
ortho position due to the presence of the methyl group at the
position para to the oxygen, and the subsequent intramolecular
reaction formed the phenoxaborin skeleton. Similarly, tri-p-
tolylamine 1o underwent regioselective borylation at the
position ortho to the nitrogen, and the successive nucleophilic
substitution with mesitylmagnesium bromide furnished
phenazaborin analogue 6 in 90% yield.
Notably, multiple borylation15 of polycyclic aromatic
compounds was successful with the use of excess BI3 (Scheme
4). In the presence of 4.0 equiv of BI3, double borylation
Scheme 4. Multiple Borylation of Pyrene, Perylene,
a
Ferrocene, and 3,3′-Dimethylbiphenyl
Figure 1. Kohn−Sham highest occupied molecular orbital and
relative Gibbs free energies (ΔG) for borylated intermediates of (a) 3-
chloro-o-xylene 1b, (b) diphenyl ether 1k, and (c) 9,10-diphenylan-
thracene 1e calculated at the B3LYP/6-31G(d) level of theory. tr,
theoretical ratio; er, experimental ratio. The theoretical ratio of
regioisomers was determined using the equilibrium constant (K =
exp(ΔG/RT)).
takes place at the most accessible carbon, where the HOMO is
localized to a certain extent.
To demonstrate the utility of this method, phenoxaborin19
and phenazaborin20analogues were synthesized (Scheme 3).
Di-p-tolyl ether 1n was reacted with BI3 at 240 °C, followed by
a
Yields were determined by 1H NMR using 1,1,2,2-tetrachloroethane
as an internal standard, and isolated yields are shown in parentheses.
Scheme 3. Synthesis of Phenoxaborin and Phenazaborin
Analogues
a
occurred at the 2,7-position of pyrene and afforded 7 in 51%
yield. Furthermore, the use of 8.0 equiv of BI3 afforded
2,5,8,11-tetraborylated perylene 8 in 36% yield. Ferrocene and
3,3′-dimethylbiphenyl also underwent multiple borylations and
furnished the corresponding tetra- and diborylated products 9
and 10 in 39% and 50% yield, respectively.
In summary, we successfully developed a methodology for
the electrophilic C−H borylation of arenes with boron
triiodide, which enabled the direct synthesis of arylboronates,
boronic acids, and borates. The DFT calculations suggested
that this reaction is kinetically controlled to take place at the
most sterically accessible carbon, where the HOMO is
localized to a certain extent. Furthermore, we successfully
synthesized phenoxaborin and phenazaborin analogues by the
intermolecular and intramolecular electrophilic C−H boryla-
tion of di-p-tolyl ether and tri-p-tolylamine, respectively. The
method was also extended to regioselective multiple borylation
by simply using excess BI3, producing multiborylated aromatic
a
Yields were determined by 1H NMR using 1,1,2,2-tetrachloroethane
as an internal standard, and isolated yields are shown in parentheses.
C
https://dx.doi.org/10.1021/acs.orglett.9b04483
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́
̂
́
(5) (a) Cote, A. P.; Benin, A. I.; Ockwig, N. W.; OKeeffe, M.;
compounds, which can provide access to novel functional
materials.21
̂
́
Matzger, A. J.; Yaghi, O. M. Science 2005, 310, 1166. (b) Cote, A. P.;
El-Kaderi, H. M.; Furukawa, H.; Hunt, J. R.; Yaghi, O. M. J. Am.
Chem. Soc. 2007, 129, 12914.
(6) Review: (a) Mkhalid, I. A. I.; Barnard, J. H.; Marder, T. B.;
Murphy, J. M.; Hartwig, J. F. Chem. Rev. 2010, 110, 890. (b) Hartwig,
J. F. Acc. Chem. Res. 2012, 45, 864.
ASSOCIATED CONTENT
* Supporting Information
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sı
The Supporting Information is available free of charge at
(7) Ir catalyst: (a) Cho, J.-Y.; Tse, M. K.; Holmes, D.; Maleczka, R.
E., Jr.; Smith, M. R., III Science 2002, 295, 305. (b) Ishiyama, T.;
Takagi, J.; Ishida, K.; Miyaura, N.; Anastasi, N. R.; Hartwig, J. F. J.
Am. Chem. Soc. 2002, 124, 390. Rh catalyst: (c) Cho, J.-Y.; Iverson,
C. N.; Smith, M. R., III J. Am. Chem. Soc. 2000, 122, 12868.
(d) Shimada, S.; Batsanov, A. S.; Howard, J. A. K.; Marder, T. B.
Angew. Chem., Int. Ed. 2001, 40, 2168. (e) Bheeter, C. B.; Chowdhury,
A. D.; Adam, R.; Jackstell, R.; Beller, M. Org. Biomol. Chem. 2015, 13,
10336. Pt catalyst: (f) Furukawa, T.; Tobisu, M.; Chatani, N. J. Am.
Chem. Soc. 2015, 137, 12211. (g) Takaya, J.; Ito, S.; Nomoto, H.;
Saito, N.; Kirai, N.; Iwasawa, N. Chem. Commun. 2015, 51, 17662.
(h) Furukawa, T.; Tobisu, M.; Chatani, N. Bull. Chem. Soc. Jpn. 2017,
90, 332.
https://pubs.acs.org/doi/10.1021/acs.orglett.9b04483.
Synthesis, analytical data, NMR spectra, DFT studies
(PDF)
AUTHOR INFORMATION
Corresponding Author
■
Takuji Hatakeyama − Kwansei Gakuin University,
Sanda, Japan; orcid.org/0000-0002-7483-9525;
Email: hatake@kwansei.ac.jp
Other Authors
(8) Fe catalyst: (a) Yan, G.; Jiang, Y.; Kuang, C.; Wang, S.; Liu, H.;
Zhang, Y.; Wang, J. Chem. Commun. 2010, 46, 3170. (b) Dombray,
T.; Werncke, C. G.; Jiang, S.; Grellier, M.; Vendier, L.; Bontemps, S.;
Sortais, J.-B.; Sabo-Etienne, S.; Darcel, C. J. Am. Chem. Soc. 2015, 137,
4062. Co catalyst: (c) Obligacion, J. V.; Semproni, S. P.; Chirik, P. J.
J. Am. Chem. Soc. 2014, 136, 4133. (d) Obligacion, J. V.; Semproni, S.
P.; Pappas, I.; Chirik, P. J. J. Am. Chem. Soc. 2016, 138, 10645. Ni
catalyst: (e) Zhang, H.; Hagihara, S.; Itami, K. Chem. Lett. 2015, 44,
779. (f) Furukawa, T.; Tobisu, M.; Chatani, N. Chem. Commun. 2015,
51, 6508.
Susumu Oda − Kwansei Gakuin University, Sanda,
Japan; orcid.org/0000-0003-1088-1932
Kenta Ueura − Kwansei Gakuin University, Sanda, Japan
Bungo Kawakami − Kwansei Gakuin University, Sanda,
Japan
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.orglett.9b04483
(9) Ingleson, M. J. Synlett 2012, 23, 1411.
Notes
(10) (a) Hurd, D. T. J. Am. Chem. Soc. 1948, 70, 2053.
(b) Muetterties, E. L. J. Am. Chem. Soc. 1959, 81, 2597. (c) Bujwid,
Z. J.; Gerrard, W.; Lappert, M. F. Chem. Ind. 1959, 1091.
(d) Muetterties, E. L. J. Am. Chem. Soc. 1960, 82, 4163.
(e) Muetterties, E. L.; Tebbe, F. N. Inorg. Chem. 1968, 7, 2663.
(11) (a) De Vries, T. S.; Prokofjevs, A.; Harvey, J. N.; Vedejs, E. J.
Am. Chem. Soc. 2009, 131, 14679. (b) Prokofjevs, A.; Vedejs, E. J. Am.
Chem. Soc. 2011, 133, 20056. (c) Prokofjevs, A.; Kampf, J. W.; Vedejs,
E. Angew. Chem., Int. Ed. 2011, 50, 2098. (d) Prokofjevs, A.; Jermaks,
J.; Borovika, A.; Kampf, J. W.; Vedejs, E. Organometallics 2013, 32,
6701.
(12) (a) Del Grosso, A.; Pritchard, R. G.; Muryn, C. A.; Ingleson, M.
J. Organometallics 2010, 29, 241. (b) Del Grosso, A.; Singleton, P. J.;
Muryn, C. A.; Ingleson, M. J. Angew. Chem., Int. Ed. 2011, 50, 2102.
(c) Del Grosso, A.; Helm, M. D.; Solomon, S. A.; Caras-Quintero, D.;
Ingleson, M. J. Chem. Commun. 2011, 47, 12459. (d) Solomon, S. A.;
Del Grosso, A.; Clark, E. R.; Bagutski, V.; McDouall, J. J. W.;
Ingleson, M. J. Organometallics 2012, 31, 1908. (e) Bagutski, V.;
DelGrosso, A.; Carrillo, J. A.; Cade, I. A.; Helm, M. D.; Lawson, J. R.;
Singleton, P. J.; Solomon, S. A.; Marcelli, T.; Ingleson, M. J. J. Am.
Chem. Soc. 2013, 135, 474. (f) Del Grosso, A.; Ayuso Carrillo, J.;
Ingleson, M. J. Chem. Commun. 2015, 51, 2878. (g) Escande, A.;
Crossley, D. L.; Cid, J.; Cade, I. A.; Vitorica-Yrezabal, I.; Ingleson, M.
J. Dalton Trans. 2016, 45, 17160. (h) McGough, J. S.; Cid, J.;
Ingleson, M. J. Chem. - Eur. J. 2017, 23, 8180. (i) Iqbal, S. A.; Cid, J.;
Procter, R. J.; Uzelac, M.; Yuan, K.; Ingleson, M. J. Angew. Chem., Int.
Ed. 2019, 58, 15381.
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This study was supported by a Grant-in-Aid for Scientific
Research (JP18H02051), Challenging Research (Exploratory,
JP17K19164, 19K22191), and Grant-in-Aid for Early-Career
Scientists (18K14228) from the Japan Society for the
Promotion of Science (JSPS), Sumitomo Foundation,
Kinoshita Memorial Enterprise, and Hyogo Science and
Technology Association.
REFERENCES
■
(1) (a) Miyaura, N.; Suzuki, A. Chem. Rev. 1995, 95, 2457.
(b) Miyaura, N. Bull. Chem. Soc. Jpn. 2008, 81, 1535. (c) Hall, D. G.
Boronic Acids: Preparation and Applications in Organic Synthesis,
Medicine and Materials, 2nd ed.; Wiley: Weinheim, 2011. (d) Suzuki,
A. Angew. Chem., Int. Ed. 2011, 50, 6722.
(2) (a) Ishihara, K.; Ohara, S.; Yamamoto, H. J. Org. Chem. 1996,
61, 4196. (b) Sakakura, A.; Ohkubo, T.; Yamashita, R.; Akakura, M.;
Ishihara, K. Org. Lett. 2011, 13, 892. (c) Zheng, H.; Ghanbari, S.;
Nakamura, S.; Hall, D. G. Angew. Chem., Int. Ed. 2012, 51, 6187.
(d) Li, Y.; Molina de La Torre, J. A.; Grabow, K.; Bentrup, U.; Junge,
̈
K.; Zhou, S.; Bruckner, A.; Beller, M. Angew. Chem., Int. Ed. 2013, 52,
11577. (e) Noda, H.; Asada, Y.; Shibasaki, M.; Kumagai, N. Chem.
Commun. 2017, 53, 7447.
(13) (a) Laaziri, H.; Bromm, L. O.; Lhermitte, F.; Gschwind, R. M.;
Knochel, P. J. Am. Chem. Soc. 1999, 121, 6940. (b) Goldfuss, B.;
Knochel, P.; Bromm, L. O.; Knapp, K. Angew. Chem., Int. Ed. 2000,
39, 4136. (c) Genaev, A. M.; Salnikov, G. E.; Shubin, V. G.; Nagy, S.
M. Chem. Commun. 2000, 1587. (d) Varela, J. A.; Pena, D.; Goldfuss,
B.; Denisenko, D.; Kulhanek, J.; Polborn, K.; Knochel, P. Chem. - Eur.
J. 2004, 10, 4252. (e) Goldfuss, B. Chem. - Eur. J. 2009, 15, 12856.
(f) Ishida, N.; Moriya, T.; Goya, T.; Murakami, M. J. Org. Chem.
2010, 75, 8709. (g) Hatakeyama, T.; Hashimoto, S.; Seki, S.;
Nakamura, M. J. Am. Chem. Soc. 2011, 133, 18614. (h) Stahl, T.;
Muether, K.; Ohki, Y.; Tatsumi, K.; Oestreich, M. J. Am. Chem. Soc.
(3) (a) Baker, S. J.; Zhang, Y. K.; Akama, T.; Lau, A.; Zhou, H.;
Hernandez, V.; Mao, W.; Alley, M. R. K.; Sanders, V.; Plattner, J. J.
Med. Chem. 2006, 49, 4447. (b) Rock, F. L.; Mao, W.; Yaremchuk, A.;
́
Tukalo, M.; Crepin, T.; Zhou, H.; Zhang, Y.; Hernandez, V.; Akama,
T.; Baker, S. J.; Plattner, J. J.; Shapiro, L.; Martinis, S. A.; Benkovic, S.
J.; Cusack, S.; Alley, M. R. K. Science 2007, 316, 1759. (c) Adamczyk-
Wozniak, A.; Borys, K. M.; Sporzynski, A. Chem. Rev. 2015, 115,
5224.
(4) (a) James, T. D.; Sandanayake, S. K. R. A.; Shinkai, S. Nature
1995, 374, 345. (b) Zhao, J.; Davidson, M. D.; Mahon, M. F.; Kociok-
̈
Kohn, G.; James, T. D. J. Am. Chem. Soc. 2004, 126, 16179.
D
https://dx.doi.org/10.1021/acs.orglett.9b04483
Org. Lett. XXXX, XXX, XXX−XXX

Organic Letters
pubs.acs.org/OrgLett
Letter
́
́
2013, 135, 10978. (i) Legare, M.-A.; Courtemanche, M.-A.; Rochette,
́
́
E.; Fontaine, F.-G. Science 2015, 349, 513. (j) Legare, M.-A.;
́
́
Rochette, E.; Legare Lavergne, J.; Bouchard, N.; Fontaine, F.-G.
Chem. Commun. 2016, 52, 5387. (k) Chernichenko, K.; Lindqvist, M.;
Kotai, B.; Nieger, M.; Sorochkina, K.; Papai, I.; Repo, T. J. Am. Chem.
Soc. 2016, 138, 4860. (l) Yin, Q.; Klare, H. F. T.; Oestreich, M.
́
́
Angew. Chem., Int. Ed. 2017, 56, 3712. (m) Legare Lavergne, J.;
Jayaraman, A.; Misal Castro, L. C.; Rochette, E.; Fontaine, F.-G. J.
Am. Chem. Soc. 2017, 139, 14714. (n) Liu, Y.-L.; Kehr, G.; Daniliuc,
C. G.; Erker, G. Chem. - Eur. J. 2017, 23, 12141. (o) Kitani, F.; Takita,
R.; Imahori, T.; Uchiyama, M. Heterocycles 2017, 95, 158. (p) Zhang,
S.; Han, Y.; He, J.; Zhang, Y. J. Org. Chem. 2018, 83, 1377. (q) Zhong,
Q.; Qin, S.; Yin, Y.; Hu, J.; Zhang, H. Angew. Chem., Int. Ed. 2018, 57,
14891. (r) Lv, J.; Chen, X.; Xue, X.-S.; Zhao, B.; Liang, Y.; Wang, M.;
Jin, L.; Yuan, Y.; Han, Y.; Zhao, Y.; Lu, Y.; Zhao, J.; Sun, W.-Y.; Houk,
K. N.; Shi, Z. Nature 2019, 575, 336.
(14) (a) Hatakeyama, T.; Shiren, K.; Nakajima, K.; Nomura, S.;
Nakatsuka, S.; Ni, J.; Ono, Y.; Ikuta, T.; Kinoshita, K. Adv. Mater.
2016, 28, 2777. (b) Matsui, K.; Oda, S.; Yoshiura, K.; Nakajima, K.;
Yasuda, N.; Hatakeyama, T. J. Am. Chem. Soc. 2018, 140, 1195.
(c) Fukagawa, H.; Oono, T.; Iwasaki, Y.; Hatakeyama, T.; Shimizu, T.
Mater. Chem. Front. 2018, 2, 704. (d) Nakatsuka, S.; Yasuda, N.;
Hatakeyama, T. J. Am. Chem. Soc. 2018, 140, 13562. (e) Kondo, Y.;
Yoshiura, K.; Kitera, S.; Nishi, H.; Oda, S.; Gotoh, H.; Sasada, Y.;
Yanai, M.; Hatakeyama, T. Nat. Photonics 2019, 13, 678.
(15) Ir-catalyzed multiple borylation: (a) Coventry, D. N.; Batsanov,
A. S.; Goeta, J. A. K.; Howard, A. E.; Marder, T. B.; Perutz, R. N.
Chem. Commun. 2005, 2172. (b) Fujinaga, M.; Murafuji, T.; Kurotobi,
K.; Sugihara, Y. Tetrahedron 2009, 65, 7115. (c) Teraoka, T.; Hiroto,
S.; Shinokubo, H. Org. Lett. 2011, 13, 2532. (d) Hitosugi, S.;
Nakamura, Y.; Matsuno, T.; Nakanishi, W.; Isobe, H. Tetrahedron
Lett. 2012, 53, 1180. (e) Eliseeva, M. N.; Scott, L. T. J. Am. Chem. Soc.
2012, 134, 15169. (f) Liu, Z.; Wang, Y.; Chen, Y.; Liu, J.; Fang, Q.;
Kleeberg, C.; Marder, T. B. J. Org. Chem. 2012, 77, 7124. (g) Palmer,
W. N.; Obligacion, J. V.; Pappas, I.; Chirik, P. J. J. Am. Chem. Soc.
2016, 138, 766.
(16) The use of equimolar or 4.0 equiv of BI3 gave 2b in 4% and
25% yield, respectively. No diborylated product was obtained. See the
Supporting Information for details.
(17) The use of equimolar or excess BI3 resulted in lower yield or a
mixture of monoborylated and diborylated products. See the
Supporting Information for details.
(18) See the Supporting Information for details of the recoveries of
anthracene (1d) and triphenylene (1h). The exact recoveries of
excess substrates could not be determined in most cases due to the
removal together with 1,2,4-trichlorobenzene or the peak overlap.
́
(19) (a) Melaïmi, M.; Sole, S.; Chiu, C.-W.; Wang, H.; Gabbaï, F. P.
Inorg. Chem. 2006, 45, 8136. (b) Kobayashi, J.; Kato, K.; Agou, T.;
Kawashima, T. Chem. - Asian J. 2009, 4, 42. (c) Numata, M.; Yasuda,
T.; Adachi, C. Chem. Commun. 2015, 51, 9443. (d) Igarashi, T.;
Tobisu, M.; Chatani, N. Angew. Chem., Int. Ed. 2017, 56, 2069.
(20) (a) Agou, T.; Kobayashi, J.; Kawashima, T. Org. Lett. 2006, 8,
2241. (b) Agou, T.; Kobayashi, J.; Kawashima, T. Chem. Commun.
2007, 3204. (c) Agou, T.; Kojima, T.; Kobayashi, J.; Kawashima, T.
Org. Lett. 2009, 11, 3534. (d) Agou, T.; Arai, H.; Kawashima, T.
Chem. Lett. 2010, 39, 612. (e) Park, I. S.; Numata, M.; Adachi, C.;
Yasuda, T. Bull. Chem. Soc. Jpn. 2016, 89, 375. (f) Ishikawa, Y.;
Suzuki, K.; Hayashi, K.; Nema, S.; Yamashita, M. Org. Lett. 2019, 21,
1722.
́
(21) (a) Waller, P. J.; Gandara, F.; Yaghi, O. M. Acc. Chem. Res.
2015, 48, 3053. (b) Diercks, C. S.; Yaghi, O. M. Science 2017, 355,
eaal1585. (c) Lohse, M. S.; Bein, T. Adv. Funct. Mater. 2018, 28,
1705553. (d) Figueira-Duarte, T. M.; Mu
̈
llen, K. Chem. Rev. 2011,
111, 7260. (e) Wu
̈
rthner, F.; Saha-Moller, C. R.; Fimmel, B.; Ogi, S.;
̈
Leowanawat, P.; Schmidt, D. Chem. Rev. 2016, 116, 962. (f) Gupta, R.
K.; Sudhakar, A. A. Langmuir 2019, 35, 2455.
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Org. Lett. XXXX, XXX, XXX−XXX