Palladium-catalyzed oxidative coupling of arylboronic acid with isocyanide to form aromatic carboxylic acids

Article abstract of DOI:10.1039/c7ob01428g

A valuable palladium-catalyzed oxidative coupling of aryl- and alkenyl borides with isocyanide for the synthesis of corresponding carboxylic acids has been developed. With wide substrate scopes and good functional group tolerance, this reaction offers corresponding carboxylic acids in moderate to excellent yields.

Full text of DOI:10.1039/c7ob01428g

View Article Online
View Journal
Organic &
Biomolecular
Chemistry
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: Y. Zhu, Z. Chen, K.
Liu, F. Zhang and Q. Yuan, Org. Biomol. Chem., 2017, DOI: 10.1039/C7OB01428G.
This is an Accepted Manuscript, which has been through the
Volume 14 Number
1 7 January 2016 Pages 1–372
Royal Society of Chemistry peer review process and has been
accepted for publication.
Organic &
Biomolecular
Chemistry
www.rsc.org/obc
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1477-0520
COMMUNICATION
Takeharu Haino et al.
Solvent-induced emission of organogels based on tris(phenylisoxazolyl)
benzene
rsc.li/obc

Please do not adjust margins
Organic & Biomolecular Chemistry
Page 1 of 5
View Article Online
DOI: 10.1039/C7OB01428G
Journal Name
ARTICLE
Palladium-Catalyzed Oxidative Coupling of Arylbororic Acid with
Isocyanide to form Aromatic Carboxylic Acid
Zhen-Bang Chen,a Kui Liu,a Fang-Ling Zhang,a Qing Yuan,a Yong-Ming Zhu*a
Received 00th January 20xx,
Accepted 00th January 20xx
A valuable palladium-catalyzed oxidative coupling of aryl- and alkenyl borides with isocyanide for the synthesis of
corresponding carboxylic acids has been developed. With wide substrate scopes and good functional group tolerance, this
reaction offers corresponding carboxylic acids in moderate to excellent yields.
DOI: 10.1039/x0xx00000x
www.rsc.org/
X
R1
+
CO
Introduction
X = I, Br, Cl
M
COOH
COOH
M
R1
Aromatic carboxylic acids are key structural motifs in organic
chemistry and their derivatives are widely present in
pharmaceuticals, agrochemicals and pigments.1 Conventional
methods for synthesizing aromatic carboxylic acids include the
oxidation of aromatic compounds,2, 3 the reaction of Grignard
and aryl lithium or zinc reagents with carbon dioxide
(CO2)4 (Scheme 1, a) and the hydrolysis of aromatic
nitriles (Scheme 1, b).5 Unfortunately, these methods suffer
from many inherent drawbacks including poor functional
groups tolerance, low selectivity, limited substrate scope and
numerous side reactions. Recently, several reports6 have
described carboxylation process employing CO2 gas as
C1 building block with aryl halides and aryl borides under
transition metal catalyzed condition. At the same time, the
thermodynamic and kinetic stability of the CO2 molecule
imposes major challenges on the reactions, which requires the
reactions should be under high temperature and high pressure
condition. To solve the problem, in 2014, Zhou and
Chen7 introduced acetyl acetate in carboxylation process to
displace CO2 (Scheme 1, c). Subsequently, Das and co-
workers8 used oxalic acid as the C1 source under focused
microwave irradiation (Scheme 1, d). However, the drawbacks
of complex Pd@PS catalyst and the poor yields limited the
method. In addition, the carboxylation process using carbon
monoxide (CO) or versatile CO surrogates as C1 source has
+
R1
+
CO2
M
e
(e)
t
a
S
l
P
c
M = I, Br, B(OH)2,
SiEt3
a
@
d
t
a
l
P
M = MgX, ZnX, Li,
BR2, I, Br
y
s
t
W
M
(a)
,
S
I
N
(d)
COOH
R1
C
u
I
,
K
D
2
C
O
M
O
O
S
O
3
,
1
(b)
0
0
o
Pd(OAc)2
Cu(OAc)2
DMF, 100 oC
OEt
C
(c)
CN
+
H3O+
R1
this work
+
B(OH)2
R1
B(OH)2
R1
R2NC
+
Scheme 1. Methods for synthesizing aromatic carboxylic Acids
desirable.
On the other hand, isocyanides, a kind of unsaturated
molecule differing in structure from nitriles, are easily handled
liquids or solids. The functional group of isocyanides is bound
to nitrogen as opposed to carbon, which makes them possess
both nucleophilicity and electrophilicity. In the past decades,
isocyanides emerged as important C1 building blocks to
displace CO in palladium-catalyzed multicomponent reactions
(MCRs) 10 and metal-catalyzed C–H bond functionalization11
have been extensively explored. Nevertheless, the most
reported achievements mainly focus on the utility
of isocyanides insertion into C-X bonds(X=I, Br) for synthesis of
been
Nevertheless, the
reported9 in
recent
years (Scheme
1,
e).
nitrogen-containing
compounds
and
heterocyclic
handling
problem of toxic
and
compounds.12 In 2016, Wu et al.13 discovered that arylboronic
acids, anilines and isocyanides could transform into amidines
under oxidative conditions, which was the first example
for isocyanides insertion into C-B bond. Based on these
flammable gas, as well as the use of expensive ligands in the
process limited their application. Therefore, developing a mild,
operationally simple approach for the carboxylation process
with wider substrate scopes and high efficiency would be
backgrounds,
herein,
we
provide
a
new carboxylation process via palladium-catalyzed isocyanides
insertion into C-B bond for the synthesis of aromatic carboxylic
acids.
a.College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123,
China. E-mail: zhuyongming@suda.edu.cn; fax: (+86)-512-67166591.
Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/x0xx00000x
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 1
Please do not adjust margins

Please do not adjust margins
Organic & Biomolecular Chemistry
Page 2 of 5
View Article Online
DOI: 10.1039/C7OB01428G
ARTICLE
Journal Name
instead of
2
, the yield was reduced (Table 1, entry 17). When
Results and discussion
the reaction
was run with 0.5 equiv of
We
initiated
our
investigation
by
using
4-
as
Cu(OAc)2 under O2, only 54% yield was obtained (Table 1, entry
18). Thus, the optimized reaction conditions included
Pd(OAc)2 (5 mol%) as catalyst, Cu(OAc)2 (2.0 equiv.) as oxidant,
4A MS (100 mg) as addition and DMF as solvent, under argon
at 100 oC for 24 h.
methoxyphenylboronic acid 1a and tert-butyl isocyanide
2
model substrates. When the reaction was performed in the
presence of Pd(PPh3)2Cl2 , Cu(OAc)2 and DMF under nitrogen at
100 °C for 12 h, the carboxylation product 3a was obtained
successfully in 57% yield (Table 1, entry 1). Then, we prolonged
reaction time to 24 h and used molecular sieves (4A MS) as an
additive under argon, the yield was increased to 69% (Table 1,
entry 2). Other oxidants including oxygen (Table 1, entry 6)
were tested, no carboxylative products could be detected
except for AgOAc, which indicated the acetates were
necessary for the process (Table 1, entry 3-8). Screening of
other solvents including DMSO, toluene and THF indicated
that none of them was superior to DMF (Table 1, entry 9-11),
and the use of nonpolar solvent led to an increase of side
reactions. Subsequently, various catalytic systems were
screened, employment of Pd(OAc)2 gave a better result (Table
1, entry 12-15). The results also showed that the acetates gave
a promoting effect on the reaction. In addition, reducing the
temperature led to a decrease in the yield (Table 1, entry
16). Using other isocyanides such as cyclohexyl isocyanide
With the optimized conditions established, then, we
investigated the substrate scope of the reaction. As illustrated
in Table 2, a broad range of substituted carboxylation products
were readily delivered in moderate to excellent (up to 96%)
yields. The reaction was found to tolerate a series of different
functional groups on phenyl rings, giving the corresponding
electron-withdrawing substituents were products in good
yields
withdrawing groups were all compatible with the method, and
electron-donating groups (3a 3d 3f 3n 3o) led to a higher
(3a-3k). Both electron-donating and electron-
,
,
,
,
yield. The influence of steric hindrance was not obvious (3l). In
addition, the ketone, ester, acetylamino and vinyl groups on
phenyl ring did not interfere with the reaction and provided
the respective products in moderate yields (3p
-3s). α- or β-
Naphthylboronic acid (3 3u) and dibenzothiophene-4-
t,
carboxylic acid (3v) also could be converted in satisfactory
yields (59-79%) under the standard conditions. It is of note
that the transformation of trans-2-phenylvinylboronic acid also
took place, giving 3-phenylacrylic acid in 48% yield (3w).
Unfortunately, 2-phenylethylboronic acid, used as substrate,
has been tested in our model system but no desired products
could be detected.
Table 1. Conditions optimization of the reactiona
Entry
1
Catalyst
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)2Cl2
Pd(PPh3)4
Oxidants
Cu(OAc)2
Cu(OAc)2
Cu(OTf)2
CuCl2
Solvent
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMSO
toluene
THF
Yield [%]b
57 c
69
Table 2. Substrate scope for aromatic carboxylic acids a
2
3
0
4
0
3e, 57%(R = SMe)
3f, 83%(R = NMe2)
3g, 82%(R = Ph)
3h, 64%(R = Cl)
3i, 62%(R = F)
5
CuBr2
trace
0
6
O2
7
---
0
8
AgOAc
48
3j, 82%(R = CN)
3k, 66%(R = CF3)
9
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
Cu(OAc)2
60
10
11
12
13
14
15
16
17
22
17
DMF
DMF
DMF
DMF
DMF
DMF
DMF
54
Pd(OAc)2
86
Pd(CH3CN)2Cl2
Pd2(dppf)Cl2
Pd(OAc)2
85
74
69d
32e
54f
a
Pd(OAc)2
Reaction conditions: 1a (0.8 mmol), 2 (1.5 equiv), Pd(OAc)2 (5
mol%), Cu(OAc)2 (2.0 equiv) and 4A MS (100 mg) in 2 mL of
solvent at 100 °C for 24 h in a sealed tube. Isolated yield.
18
Pd(PPh3)2Cl2
a
Reaction con ditions: All reactions were performed under
argon with 1a (0.8 mmol), 2 (1.5 equiv), catalyst (5 mol%),
oxidant (2.0 equiv) and 4A MS (100 mg) in 2 mL of solvent at
To further study the scope of the carboxylation reaction, we
examined other aromatic borides, such as pinacol
phenylboronate and potassium phenyltrifluoroborate.
Satisfactorily, the desired products were also successfully
100 °C for 24 h in a sealed tube. b Isolated yield. under N2
c
d
e
f
without 4A MS for 12 h. 80 °C. cyclohexyl isocyanide. 0.5
equiv of Cu(OAc)2 and O2 was used.
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Organic & Biomolecular Chemistry
Page 3 of 5
View Article Online
DOI: 10.1039/C7OB01428G
Journal Name
ARTICLE
obtained under the standard conditions(scheme 2, a). Notably, intermediate
B
faces two pathways. In the presence of H2O,
reacts with H2O to form the intermediate
gives
and Pd0 species, the Pd0 species is oxidized by
synthetic method as a useful tool in practical synthetic Cull to give the Pdll species and completes the catalytic cycle.
the gram-scale preparation of 3a was conducted under the intermediate
B
E
.
even lower catalyst loading (3 mol%) condition and 83% yield Subsequent reductive elimination of the intermediate
was achieved (scheme 2, b), which showed promise for this the product
E
4
contexts.
Alternatively, direct reductive elimination of intermediate
give intermediate . Finally, in the extraction process, the
intermediate is hydrolyzed to form the intermediate D,
B to
C
C
which followed by hydrolysis further to form product 3.
Scheme 2. Carboxylation reaction of other aromatic borides
.
and scalable preparation of 3a
Next, to gain insights into the reaction process, a control
experiment was performed. As depicted in scheme 3, the
introduction of a stoichiometric amount of H2O furnished
the desired product 3a and amides
4 in 28% and 25% yields
Scheme 3. Plausible reaction mechanism
(scheme 3, a), respectively. In addition, using copper(II)
trifluoroacetate hydrate (Cu(TFA)2·xH2O) instead of copper
acetate as the oxidant, only the amides
3, b), which indicated that the presence of H2O would promote
the formation of the amides . In order to exclude the
possibility that the desired product 3a was originated from the
hydrolysis of t-butylbenzamide , we tried to mix with
4 were formed(scheme
Conclusions
4
In summary, we have illustrated a novel palladium-catalyzed
carboxylation reaction by using isocyanide as carboxyl source
for the synthesis of aromatic carboxylic acids. In this reaction,
we achieved an efficient conversion from aryl- and alkenyl
borides to the corresponding carboxylic acids in the oxidative
palladium-catalyzed reaction involving isocyanide insertion
into C−B bonds. In addition, the catalytic system shows wide
functional group compatibility and high reaction activity.
4
4
2
under the standard conditions. No desired product 3a was
detected(scheme 3, c), which clarified that 3a was formed
from arylboronic acids and isocyanides.
Acknowledgements
This work was supported by the PAPD (A Project Funded by
the Priority Academic Program Development of Jiangsu Higher
Education Institutions).
Experimental
General Information.
Unless otherwise noted, all solvents were dried and freshly
distilled. TLC was performed on silica HSGF254 plates. NMR
spectra were run in a solution of deuterated chloroform
(CDCl3) with tetramethylsilane (TMS) as internal standard and
were reported in parts per million (ppm). 1H and 13C NMR
spectra were obtained at 400/101 MHz (1H/13C), respectively.
Starting materials were purchased from commercial suppliers
and used without further purification.
Scheme 3. Mechanistic studies
Based on the experimental results and literature
investigation,13 a plausible mechanism was depicted in scheme
3. Firstly, arylboronic acid
process to generate complex
isocyanide insertion to form intermediate B 14
1
undergoes a transmetalation
followed by tert-butyl
The
A
,
.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Organic & Biomolecular Chemistry
Page 4 of 5
View Article Online
DOI: 10.1039/C7OB01428G
ARTICLE
Journal Name
8.0 Hz, 2H), 7.86 (d, J = 7.9 Hz, 2H). 13C NMR (101 MHz, DMSO)
δ 166.2 (s), 134.6 (s), 132.7 (s), 132.3 (s), 130.1 (s), 125.6 (q, J =
3.7 Hz), 125.2 (s).
General procedure for the carboxylation processes.
To a solution of (0.80 mmol), tert-butyl isocyanide (1.5
1
mmol), Pd(OAc)2 (5 mol %), Cu(OAc)2 (2.0 mmol) in DMF (2.0
mL), the mixture was stirred at 100 °C for 24 h. After
completion of the reaction as indicated by TLC, poured in to
water (30 mL) and extracted by ethyl acetate (3×30 mL). The
combined organic layers were dried (Na2SO4) and evaporated.
The residue was purified on a silica gel column using petroleum
1
2-Methyl-benzoic acid(3l)8 White solid(82 mg, 75% yield). H
NMR (400 MHz, DMSO) δ 12.96 (s, 1H), 7.97 (d, J = 7.7 Hz, 1H),
7.56 (t, J = 7.4 Hz, 1H), 7.41 (d, J = 6.9 Hz, 2H), 2.66 (s, 3H). 13C
NMR (101 MHz, DMSO) δ 168.8 (s), 139.1 (s), 131.6 (d, J = 18.7
Hz), 130.6 – 130.2 (m), 125.9 (s), 21.3 (s).
3-Methyl-benzoic acid(3m)8 White solid(88 mg, 81% yield).
1H NMR (400 MHz, CDCl3) δ 12.58 (s, 1H), 7.93 (d, J = 7.8 Hz,
2H), 7.42 (d, J = 7.4 Hz, 1H), 7.36 (t, J = 7.5 Hz, 1H), 2.42 (s,
3H).13C NMR (101 MHz, CDCl3) δ 172.9 (s), 138.4 (s), 134.8 (s),
130.9 (s), 129.4 (s), 128.5 (s), 127.5 (s), 21.4 (s).
Benzo[1,3]dioxole-5-carboxylic acid(3n)7 White solid(121 mg,
91% yield). 1H NMR (400 MHz, DMSO) δ 7.54 (d, J = 6.9 Hz, 1H),
7.35 (s, 1H), 6.98 (d, J = 7.8 Hz, 1H), 6.11 (s, 2H).13C NMR (101
MHz, DMSO) δ 166.7 (s), 151.2 (s), 147.5 (s), 125.0 (s), 124.7
(s), 108.8 (s), 108.1 (s), 102.0 (s).
ether/EtOAc as the eluent to give the pure target product 3.
4-Methoxy-benzoic acid(3a)8 White solid(105 mg, 86% yield).
1H NMR (400 MHz, DMSO) δ 12.62 (s, 1H), 7.90 (d, J = 8.2 Hz,
2H), 7.01 (d, J = 6.5 Hz, 2H), 3.80 (s, 3H). 13C NMR (101 MHz,
DMSO) δ 167.1 (s), 162.9 (s), 131.4 (s), 123.0 (s), 113.7 (s), 55.3
(s).
Benzoic acid(3b)8 White solid(63 mg, 64% yield). 1H NMR
(400 MHz, CDCl3) δ 10.76 (s, 1H), 8.14 (d, J = 7.3 Hz, 2H), 7.63
(t, J = 7.4 Hz, 1H), 7.49 (t, J = 7.6 Hz, 2H). 13C NMR (101 MHz,
CDCl3) δ 172.5 (s), 134.0 (s), 130.4 (s), 129.5 (s), 128.6 (s).
3,4,5-Trimethoxy-benzoic acid(3o)16 White solid(163 mg, 96%
yield). 1H NMR (400 MHz, CDCl3) δ 7.39 (s, 2H), 3.93 (s, 9H).13C
NMR (101 MHz, CDCl3) δ 171.7 (s), 153.1 (s), 143.1 (s), 124.2
(s), 107.5 (s), 61.1 (s), 56.4 (s).
4-Methyl-benzoic acid(3c)8 White solid(89 mg, 82% yield). H
1
NMR (400 MHz, CDCl3) δ 12.24 (s, 1H), 8.01 (d, J = 8.0 Hz, 2H),
7.27 (d, J = 7.9 Hz, 2H), 2.43 (s, 3H). 13C NMR (101 MHz, CDCl3)
δ 172.7 (s), 144.8 (s), 130.4 (s), 129.4 (s), 126.8 (s), 21.9 (s).
4-Benzyloxy-benzoic acid(3d)15 White solid(169 mg, 93%
1
4-Acetyl-benzoic acid(3p)8 White solid(78 mg, 60% yield). H
1
NMR (400 MHz, DMSO) δ 13.28 (s, 1H), 8.05 (s, 4H), 2.62 (s,
3H).13C NMR (101 MHz, DMSO) δ 197.7 (s), 166.7 (s), 139.8 (s),
134.5 (s), 129.6 (s), 128.3 (s), 27.0 (s).
yield). H NMR (400 MHz, DMSO) δ 12.61 (s, 1H), 7.89 (d, J =
8.5 Hz, 2H), 7.46 (d, J = 7.2 Hz, 2H), 7.40 (t, J = 7.2 Hz, 2H), 7.37
– 7.32 (m, 1H), 7.10 (d, J = 8.3 Hz, 2H), 5.18 (s, 2H). 13C NMR
(101 MHz, DMSO) δ 167.0 (s), 161.9 (s), 136.5 (s), 131.3 (s),
128.5 (s), 127.9 (d, J = 19.3 Hz), 123.2 (s), 114.6 (s), 69.5 (s).
4-Methylsulfanyl-benzoic acid(3e)3i White solid(76 mg, 57%
yield). 1H NMR (400 MHz, CDCl3) δ 8.01 (d, J = 8.1 Hz, 2H), 7.28
(d, J = 8.3 Hz, 2H), 2.54 (s, 3H). 13C NMR (101 MHz, CDCl3) δ
171.6 (s), 146.9 (s), 130.6 (s), 125.4 (s), 125.0 (s), 14.9 (s).
4-Dimethylamino-benzoic acid(3f)6e White solid(110 mg, 83%
yield). 1H NMR (400 MHz, CDCl3) δ 7.99 (d, J = 8.6 Hz, 2H), 6.72
(d, J = 8.5 Hz, 2H), 3.07 (s, 6H). 13C NMR (101 MHz, CDCl3) δ
172.2 (s), 153.9 (s), 132.2 (s), 116.2 (s), 110.9 (s), 40.3 (s).
Biphenyl-4-carboxylic acid(3g)7 White solid(129 mg, 82%
Terephthalic acid monomethyl ester(3q)6e White solid(89 mg,
1
62% yield). H NMR (400 MHz, DMSO) δ 13.33 (s, 1H), 8.06 (s,
4H), 3.88 (s, 3H).13C NMR (101 MHz, DMSO) δ 166.6 (s), 165.6
(s), 134.8 (s), 133.2 (s), 129.6 (s), 129.4 (s), 52.5 (s).
4-Acetylamino-benzoic acid(3r)16 White solid(99 mg, 70%
yield). 1H NMR (400 MHz, DMSO) δ 12.64 (s, 1H), 10.23 (s, 1H),
7.87 (d, J = 8.4 Hz, 2H), 7.68 (d, J = 8.5 Hz, 2H), 2.08 (s, 3H). 13
C
NMR (101 MHz, DMSO) δ 168.9 (s), 167.0 (s), 143.4 (s), 130.4
(s), 124.9 (s), 118.2 (s), 24.2 (s).
1
4-Vinyl-benzoic acid(3s)6d White solid(58 mg, 49% yield). H
NMR (400 MHz, CDCl3) δ 8.08 (d, J = 8.2 Hz, 2H), 7.50 (d, J = 8.2
Hz, 2H), 6.77 (dd, J = 17.6, 10.9 Hz, 1H), 5.90 (d, J = 17.6 Hz,
1H), 5.42 (d, J = 10.9 Hz, 1H). 13C NMR (101 MHz, CDCl3) δ
172.1 (s), 143.0 (s), 136.1 (s), 130.7 (s), 128.5 (s), 126.4 (s),
117.1 (s).
Naphthalene-2-carboxylic acid(3t)7 White solid(82 mg, 59%
1
yield). H NMR (400 MHz, CDCl3) δ 8.74 (s, 1H), 8.14 (dd, J =
1
yield). H NMR (400 MHz, DMSO) δ 12.97 (s, 1H), 8.03 (d, J =
8.4 Hz, 2H), 7.81 (d, J = 8.4 Hz, 2H), 7.74 (d, J = 7.7 Hz, 2H), 7.51
(t, J = 7.5 Hz, 2H), 7.43 (t, J = 7.3 Hz, 1H). 13C NMR (101 MHz,
DMSO) δ 167.1 (s), 144.3 (s), 139.0 (s), 130.0 (s), 129.6 (s),
129.1 (s), 128.3 (s), 126.9 (d, J = 14.7 Hz).
4-Chloro-benzoic acid(3h)8 White solid(80 mg, 64% yield). H
1
8.6, 1.5 Hz, 1H), 8.00 (d, J = 8.0 Hz, 1H), 7.92 (t, J = 7.8 Hz, 2H),
7.60 (dt, J = 22.4, 7.4 Hz, 2H). 13C NMR (101 MHz, CDCl3) δ
172.3 (s), 136.1 (s), 132.6 (s), 132.3 (s), 129.7 (s), 128.8 (s),
128.5 (s), 128.0 (s), 126.9 (s), 126.7 (s), 125.5 (s).
NMR (400 MHz, DMSO) δ 7.94 (d, J = 8.0 Hz, 2H), 7.56 (d, J =
7.3 Hz, 2H). 13C NMR (101 MHz, DMSO) δ 166.5 (s), 137.8 (s),
131.2 (s), 129.7 (s), 128.8 (s).
1
4-Fluoro-benzoic acid(3i)8 White solid(69 mg, 62% yield). H
Naphthalene-1-carboxylic acid(3u)7 White solid(109 mg, 79%
yield). 1H NMR (400 MHz, CDCl3) δ 11.09 (s, 1H), 9.11 (d, J = 8.6
Hz, 1H), 8.44 (d, J = 7.3 Hz, 1H), 8.11 (d, J = 8.1 Hz, 1H), 7.93 (d,
J = 8.2 Hz, 1H), 7.68 (dd, J = 8.4, 7.1 Hz, 1H), 7.57 (dd, J = 13.2,
8.0 Hz, 2H). 13C NMR (101 MHz, CDCl3) δ 173.3 (s), 134.8 (s),
134.1 (s), 132.0 (s), 131.8 (s), 128.9 (s), 128.3 (s), 126.5 (s),
126.1 (s), 125.7 (s), 124.7 (s).
Dibenzothiophene-4-carboxylic acid(3v)17 White solid(120
mg, 66% yield). 1H NMR (400 MHz, DMSO) δ 8.65 (d, J = 7.9 Hz,
1H), 8.43 (d, J = 7.0 Hz, 1H), 8.18 (d, J = 7.5 Hz, 1H), 8.06 (d, J =
NMR (400 MHz, CDCl3) δ 12.66 – 10.82 (m, 1H), 8.19 – 8.10 (m,
2H), 7.16 (t, J = 8.4 Hz, 2H). 13C NMR (101 MHz, CDCl3) δ 171.3
(s), 133.1 (d, J = 9.6 Hz), 125.6 (d, J = 2.9 Hz), 116.0 (s), 115.8
(s).
1
4-Cyano-benzoic acid(3j)8 White solid(97 mg, 82% yield). H
NMR (400 MHz, DMSO) δ 13.54 (s, 1H), 8.06 (s, 2H), 7.96 (s,
2H). 13C NMR (101 MHz, DMSO) δ 166.0 (s), 134.9 (s), 132.6 (s),
129.9 (s), 118.2 (s), 115.1 (s).
4-Trifluoromethyl-benzoic acid(3k)7 White solid(100 mg, 66%
1
yield). H NMR (400 MHz, DMSO) δ 13.48 (s, 1H), 8.13 (d, J =
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Please do not adjust margins
Organic & Biomolecular Chemistry
Page 5 of 5
View Article Online
DOI: 10.1039/C7OB01428G
Journal Name
ARTICLE
8.8 Hz, 1H), 7.66 (t, J = 7.7 Hz, 1H), 7.58 – 7.51 (m, 2H). 13C
NMR (101 MHz, DMSO) δ 167.2 (s), 140.4 (s), 139.8 (s), 136.5
(s), 133.9 (s), 129.0 (s), 127.5 (s), 126.3 (s), 124.8 (d, J = 3.4 Hz),
122.7 (s), 122.1 (s).
Ed. 2013, 52, 12119; (i) A. Correa, T. Leon, R. Martin, J. Am.
Chem. Soc. 2014, 136, 1062.
R. Zheng, Q.-Z. Zhou, H.-N. Gu, H.-J. Jiang, J.-S. Wu, Z.-N. Jin,
D.-M. Han, G.-L. Dai, R. Chen, Tetrahedron Letters 2014,
55, 5671.
7
1
3-Phenyl-acrylic acid(3w)8 White solid(57 mg, 48% yield). H
8
9
A. K. Shil, S. Kumar, C. B. Reddy, S. Dadhwal, V. Thakur, P.
Das, Org. Lett. 2015, 17, 5352.
NMR (400 MHz, CDCl3) δ 11.23 (s, 1H), 7.80 (d, J = 15.7 Hz, 1H),
7.56 (s, 2H), 7.41 (s, 3H), 6.46 (d, J = 15.4 Hz, 1H). 13C NMR (101
MHz, CDCl3) δ 172.8 (s), 147.3 (s), 134.2 (s), 130.9 (s), 129.1 (s),
128.5 (s), 117.5 (s).
N-tert-Butyl-4-methoxy-benzamide(4)12g White solid. 1H
NMR (400 MHz, CDCl3) δ 7.69 (d, J = 8.7 Hz, 2H), 6.90 (d, J = 8.7
Hz, 2H), 5.88 (s, 1H), 3.84 (s, 3H), 1.47 (s, 9H). 13C NMR (101
MHz, CDCl3) δ 166.61 (s), 162.00 (s), 128.59 (s), 113.77 (s),
77.48 (s), 77.16 (s), 76.84 (s), 55.54 (s), 51.61 (s), 29.09 (s).
(a) A. Brennfhrer, H. Neumann, M. Beller, Angew. Chem. Int.
Ed. 2009, 48, 4114; (b) S. Fukuoka, Ind. Eng. Chem. Res. 2016,
55, 4830; (c) T. Ueda, H. Konishi, K. Manabe, Org. Lett. 2013,
15, 5370; (d) S. Wittmann, A. Schätz, R. N. Grass, W. J. Stark,
O. Reiser, Angew. Chem. Int. Ed. 2010, 49, 1867.
10 (a) A. V. Gulevich, A. G. Zhdanko, R. V. A. Orru, V. G.
Nenajdenko, Chem. Rev. 2010, 110, 5235; (b) T. Vlaar, E.
Ruijter, B. U. W. Maes, R. V. A. Orru, Angew. Chem. Int. Ed.
2013, 52, 7084; (c) S. Lang Chem. Soc. Rev., 2013, 42, 4867;
(d) G.-Y.-S. Qiu, Q.-P. Ding, J. Wu Chem. Soc. Rev., 2013, 42
5257.
11 B.-R. Song, B. Xu, Chem. Soc. Rev., 2017, 46, 1103.
,
12 (a) X. Jiang, T. Tang, J.-M. Wang, Z. Chen, Y.-M. Zhu, S.-J. Ji, J.
Org. Chem. 2014, 79, 5082; (b) B. Liu, M. Yin, H. Gao, W. Wu,
H. Jiang, J. Org. Chem. 2013, 78, 3009; (c) X.-Y. Fan, X. Jiang,
Notes and references
1
(a) A. Gangjee, Y. Zeng, J. J. McGuire, R. L. Kisliuk, J. Med.
Chem. 2002, 45, 1942; (b) A. F. Stepan, D. P. Walker, J.
Bauman, D. A. Price, T. A. Baillie, A. S. Kalgutkar, M. D. Aleo,
Chem. Res. Toxicol. 2011, 24, 1345.
Y. Zhang, Z.-B. Chen, Y.-M. Zhu, Org. Biomol. Chem. 2015, 13
,
10402; (d) X.-D. Fei, Z.-Y. Ge, T. Tang, Y.-M. Zhu, S.-J. Ji, J.
Org. Chem. 2012, 77, 10321; (g) Z.-B. Chen, Y. Zhang, Q.
Yuan, F.-L. Zhang, Y.-M. Zhu, J.-K. Shen J. Org. Chem. 2016,
81, 1610; (i) Y.-Y. Pan, Y.-N. Wu, Z.-Z. Chen, W.-J. Hao, G. Li,
S.-J. Tu, B. Jiang, J. Org. Chem. 2015, 80, 5764; (j) T. Fang, Q.
Tan, Z. Ding, B. Liu, B. Xu, Org. Lett. 2014, 16, 2342. (k) Q.
Gao, P. Zhou, F. Liu, W.-J. Hao, C.-S. Yao, B. Jiang, S.-J. Tu,
Chem. Commun. 2015, 51, 9519; (h) Y. Wang, Q. Zhu, Adv.
Synth. Catal. 2012, 354, 1902; (i) G. C. Senadi, T.-Y. Lu, G. K.
Dhandabani, J.-J. Wang, Org. Lett., 2017, 19, 1172.
2
(a) G. Tojo, Fernàndez, M. Oxidation of Primary Alcohols
toCarboxylic Acids: A Guide to Current Common Practice;
Springer, 2007; (b) J. H. Billman, E. E. Parker, J. Am. Chem.
Soc. 1943, 65, 2455; (c) R. Mazitschek, M. Mülbaier, A.
Giannis, Angew. Chem., Int. Ed. 2002, 41, 4059; (d) R. A.
Sheldon, Chem. Soc. Rev. 2012, 41, 1437.
3
Some moderate oxidation methods for the synthesis of
aromatic carboxylic acids, see：(a) J. E. Bäckvall, Modern
oxidation methods, Wiley-VCH, Weinheim, Germany, 2nd
edn, 2010; (b) B. R. Travis, M. Sivakumar, G. O. Hollist,
B.Borhan, Org. Lett., 2003, 5, 1031; (c) K. Lee, Y.-H. Kim, S. B.
Han, H. Kang, S. Park, W. S. Seo, J. T. Park, B. Kim, S. Chang, J.
Am. Chem. Soc. 2003, 125, 6844; (d) J. Mecinović, R. B.
13 F.-X. Zhu, Y.-H. Li, Z.-Z. Wang, R. V. A. Orru, B. U. W. Maes, X.-
F. Wu, Chem. Eur. J. 2016, 22, 7743.
14 L. Ren, X.-W. Li, N. Jiao, Org. Lett., 2016, 18, 5852.
15 C. Wiles, P. Watts, S. J. Haswell, Tetrahedron Letters, 2006,
47, 5261.
Hamed, C. J. Schofield, Angew. Chem., Int. Ed., 2009, 48
2796; (e) E. Balaraman, E. Khaskin, G. Leitus, Nat. Chem.
2013, , 122; (f) H. Li, M.-B. Hall, J. Am. Chem. Soc. 2014, 136
,
16 M.-X. Liu, C.-J. Li, Angew, Chem.Int. Ed. 2016, 55, 10806.
17 M. D. Andrews, Science of Synthesis, 2001, 10, 221.
5
,
383; (g) D. Könning, T. Olbrisch, F. D. Sypaseuth, C. C.
Tzschucke, M. Christmann, Chem. Commun., 2014, 50, 5014;
(h) G. Urgoitia, R. SanMartin, M. T. Herrero, E. Dominguez,
Chem. Commun., 2015, 51, 4799; (i) C. Santilli, I. S. Makarov,
P. Fristrup, R. Madsen, J. Org. Chem. 2016, 81, 9931; (j) T. L.
Gianetti, S. P. Annen, G. Santiso-Quinones, Angew. Chem.,
Int. Ed. 2016, 55, 1854.
4
5
(a) T.A. V. D .Knaap, T.C. Klebach, F. Visser, F. Bickelhaupt, P.
Ros, E.-J. Baerends, C.-H. Stam, Tetrahedron, 1984, 40, 765;
(b) D. J. Sheeran, J. D. Arenivar, M. Orchin, J. Organomet.
Chem., 1986, 316, 139.
(a) S. Kumar, S. K. Dixit, S. K. Awasthi, Tetrahedron Letters,
2014, 55, 3802; (b) P. Lignier, J. Estager, N. Kardos, L.
Gravouil, J. Gazza, E. Naffrechoux, M. Draye, Ultrason.
Sonochem., 2011, 18, 28; (c) F. Chemat, M. Poux, J. Berlan, J.
Chem. Soc., Perkin Trans. 2 1996, 1781; (d) J. Crosby, J.
Moilliet, J. S. Parratt, N. J. Turner, J. Chem. Soc., Perkin Trans.
1 1994, 1679.
6
(a) T. Sakakura, J. C. Choi, H. Yasuda, Chem. Rev., 2007, 107
,
2365; (b) C. Arkaitz, M. Rubén, J. Am. Chem. Soc. 2009, 131
,
15974; (c) X. Zhang, W.-Z. Zhang, L.-L. Shi, Chem. Commun.,
2012, 48, 6292; (d) C. Arkaitz, M. Rubn, Angew. Chem. Int .
Ed. 2009, 48, 6201; (e) M. K. Yusuke, E. Marelli, M. Z.
Alexandra, Chem. Commun., 2014, 50, 8010; (f) K. Kobayashi,
Y. Kondo, Org. Lett. 2009, 11, 2035; (g) N. Kielland, C. J.
Whiteoak, A. W. Kleij, Adv. Synth. Catal., 2013, 355, 2115; (h)
T. G. Ostapowicz, M. Schmitz, M. Krystof, Angew. Chem. Int .
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
Please do not adjust margins