Rhodium-Catalyzed Oxidative Coupling Reaction of Isocyanides with Alcohols or Amines and Molecular Oxygen as Oxygen Source: Synthesis of Carbamates and Ureas

Article abstract of DOI:10.1002/ejoc.201601484

The first Rh-catalyzed aerobic oxidative coupling reaction of isocyanides with alcohols or amines has been developed. The reaction takes place under very mild conditions, by using air as the terminal oxidant and oxygen-atom source. It provides a simple, efficient, and general method for the construction of N-arylcarbamates and ureas in an atom-economic manner. Moreover, the new mechanism, involving α-diazocarbonyl compounds as carbene precursors and a Rh^I/Rh^IIIcatalytic cycle with oxygen, might open up new avenues in rhodium chemistry.

Full text of DOI:10.1002/ejoc.201601484

A Journal of
Accepted Article
Title: Rhodium-Catalyzed Oxidation Coupling Reaction of Isocyanides
with Alcohols or Amines Using Molecular Oxygen as Oxygen
Source: Synthesis of Carbamates and Ureas
Authors: Xiu-Bin Bu, Zhuo Wang, Yuan-Hong Wang, Tao Jiang, Lu
Zhang, and Yu-Long Zhao
This manuscript has been accepted after peer review and appears as an
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using the Digital Object Identifier (DOI) given below. The VoR will be
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To be cited as: Eur. J. Org. Chem. 10.1002/ejoc.201601484
Link to VoR: http://dx.doi.org/10.1002/ejoc.201601484
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10.1002/ejoc.201601484
European Journal of Organic Chemistry
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Rhodium-Catalyzed Oxidation Coupling Reaction of Isocyanides with Alcohols or Amines Using
Molecular Oxygen as Oxygen Source: Synthesis of Carbamates and Ureas
Xiu-Bin Bu,[a] Zhuo Wang,[a] Yuan-Hong Wang,[a] Tao Jiang,*,[b] Lu Zhang,[a] and Yu-Long Zhao*,[a]
Dedication
Abstract: The first Rh-catalyzed aerobic oxidative oxidant have been investigated,[9] but the oxidative insertion
coupling reaction of isocyanides with various alcohols or reaction utilizing molecular oxygen as oxygen source, without
amines has been developed. The reaction takes place
subsequent cyclization, is rare. In 2015, Bi and co-workers
under very mild conditions employing air as the terminal reported the silver-catalyzed insertion reaction of isocyanides
with active methylene compounds using molecular oxygen as
efficient and general method for the construction of N- oxygen source, which occurred under high catalyst loading (30
mol%).[10] Herein, we report a novel Rh-catalyzed aerobic
oxidant and oxygen-atom source and provides a simple,
arylcarbamates and ureas in an atom-economic manner.
Moreover, the novel mechanism involving α- oxidative coupling reactions of isocyanides with alcohols or
diazocarbonyls as carbene precursors and Rh(I)/Rh(III) amines, which demonstrates broad substrate diversity. Moreover,
catalytic cycle process with oxygen might open up a new
avenues for rhodium chemistry.
the reaction employs air as the terminal oxidant and oxygen-
atom source and provides a simple, efficient and general
method for the construction of N-arylcarbamates and ureas.
Results and Discussion
Introduction
As part of our research on the carbon–carbon and carbon–
heteroatom bonds formation reactions,[11] recently, several novel
tandem reactions based on isocyanides have been developed.[12]
These results and our interests in the synthetic applications of
diazo compounds[13] prompted us to investigate the reactions of
isocyanides with α-diazocarbonyls. Unexpectedly, the reaction of
4-isocyanobiphenyl 1a (0.2 mmol) with ethyl diazoacetate (EDA)
(0.2 mmol) in MeOH (2.0 mL) could proceed in the open air at
Isocyanides are versatile building blocks in organic synthesis
because of their unique modes of reaction.[1] Accordingly,
significant advances have been made in isocyanide-based
multicomponent reactions,[2] [3+2]-cycloaddition of activated
methylene isocyanides with polar multiple bonds,[3] radical
insertions,[4] among which transition metal-catalyzed isocyanide
insertion especially represents
a fundamental and typical
chemical transformation,[5,-7,9,10] since it provides a powerful tool
for one carbon homologation. In this context, the uncontrollable
overinsertion of isocyanides is a serious issue for transition-
0
60 C for 7 h to give N-biphenylcarbamate 2a in 87% yield via
Rh(PPh3)3Cl (5 mol%)-catalyzed isocyanide insertion process
(Table 1, entry 5). No reaction was observed under otherwise
identical conditions but in the absence of EDA (entry 1), which
demonstrates that EDA is crucial for the transformation.
Decreasing the amount of Rh(PPh3)3Cl and EDA led to lower
yields (entries 2-4 and 6). In addition, the structure of α-
diazocarbonyls was also found to significantly influence the yield.
α-Diazocarbonyls L2 and L3 showed lower reactivities than α-
diazocarbonyl L1 (entries 7 and 8). No product 2a was observed
when α-diazocarbonyl L4 was employed (entry 9). Other
catalysts, such as Rh2(OAc)4, [Cp*RhCl2]2 and CuCl, were less
(Table 1, entries 10 and 11) or not effective (entry 12).
metal catalyzed insertion reactions.[6,9] As
a
result,
transformations involving isocyanide insertion have usually
appeared as an intrinsic part of tandem cyclization reactions,
encompassing a valuable method for assembling various hetero-
and carbocyclic compounds.[6,9] In stark contrast, reports on
transition-metal catalyzed insertion reactions of isocyanides with
nucleophiles, without subsequent cyclization, are rare.[7,10] In
addition, due to its abundant, natural, and environmental friendly
character, dioxygen is not only considered as an ideal oxidant,
but also an inexhaustible perfect oxygen source for
functionalization of organic molecules.[8] In the case of the
insertion reaction of isocyanides, transition-metal catalyzed
oxidative insertion reactions utilizing molecular oxygen as
Table 1. Optimization of reaction conditions.
[a]
X-B. Bu, Z. Wang, Y.-H. Wang, L. Zhang, Prof. Dr. Y.-L. Zhao
Jilin Province Key Laboratory of Organic Functional Molecular
Design & Synthesis,
Faculty of Chemistry, Northeast Normal University,
Changchun, 130024, P. R. China
Fax: (+86) 431-8509-9759
Email: zhaoyl351@nenu.edu.cn
[b]
Dr. T. Jiang
Vascular Surgery, China−Japan Union Hospital of Jilin University,
Changchun 130033, China; e-mail: loren9v9@163.com.
Supporting information for this article is given via a link at the end of
the document
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Entry
L
Catalyst
(mol%)
Rh(PPh3)3Cl (5) 10
Rh(PPh3)3Cl (5)
Rh(PPh3)3Cl (5)
Rh(PPh3)3Cl (5)
Rh(PPh3)3Cl (5)
Rh(PPh3)3Cl (3)
Rh(PPh3)3Cl (5)
Rh(PPh3)3Cl (5)
Time
[h]
Yield
[%][a]
---
20
37
73
87
60
47
20
---
35
54
also prove to be efficient partners and the desired products 2l
and 2m were obtained in 65% and 73% yields, respectively.
However, no desired product 2n was generated when tert-
butanol was subjected to the reaction. To expand the application
of this method, the reaction of isocyanide 1a with chiral (s)-(-)--
citronellol was investigated. To our delight, the desired product
2o was furnished in 60% yield and 97% ee. In addition, a
practical, gram-scale synthesis gave satisfied yield of 2a (1.11 g,
70% yield) by the reaction of 1a with MeOH under identical
reaction conditions as above for 12 h.
To further explore the generality of this new reactions of
isocyanides for nucleophiles, the rhodium-catalyzed reaction of
isocyanide 1a with various amines was investigated. As shown
in Table 3, various secondary amines such as diethylamine,
piperidine, 3,5-dimethylpiperidine, morpholine, pyrrolidine, and
diallylamine were well tolerated under the aforementioned
optimal conditions, thus affording the corresponding ureas 3a-f
in high to excellent yields. Unfortunately, no reaction was
observed when primary amines such as butylamine and aniline
were used as nucleophiles.
[equiv.]
L1 (0)
1
2
3
4
5
6
7
8
L1 (0.2)
L1 (0.4)
L1 (0.8)
L1 (1.0)
L1 (1.0)
L2 (1.0)
L3 (1.0)
L4 (1.0)
L1 (1.0)
L1 (1.0)
L1 (1.0)
7
7
7
7
7
7
8
9
Rh(PPh3)3Cl (5) 10
10
11
12
Rh2(OAc)4 (5)
[Cp*RhCl2]2 (5)
CuCl (5)
8
8
7
---
[a] Isolated yield.
Table 2.Rhodium-catalyzed reaction of isocyanide 1a with
alcohols.[a,b]
Table 3. Rhodium-catalyzed reaction of isocyanides 1a with
amines.[a,b]
[a] Reaction conditions: 1a (0.2 mmol), alcohols (2.0 mL), L1 (0.2 mmol),
Rh(PPh3)3Cl (0.01 mmol), 60 0C for 3-8 h in open air. [b] Isolated yields.
[c] The reaction was performed in toluene (1.0 mL) in the presence of (s)-(-
)--citronellol (2 .0 mmol) at 110 0C.
[a] Reaction conditions: 1a (0.2 mmol), amines (2.0 mL), L1 (0.2 mmol),
Rh(PPh3)3Cl (0.01 mmol), 60 0C for 0.5-1 h in open air. [b] Isolated yields.
Under the optimal reaction conditions, the scope and
generality of the rhodium-catalyzed coupling reactions of
isocyanide 1a for alcohols was examined and the results are
summarized in Table 2. Various primary alcohols, even including
the sterically hindered 2-methylpropan-1-ol and 2,2,2-
trifluoroethanol, could smoothly react with 4-isocyanobiphenyl 1a
to give the corresponding N-biphenylcarbamate 2a-k in high
yields. Noticeably, a variety of functional groups were tolerated
in this process, including alkyl, trifluoromethyl, phenyl,
heteroaryl and alkynyl groups. In addition to primary alcohols,
the secondary alcohols such as cyclohexanol and propan-2-ol
Next, we turned to extending the scope of the reaction with
respect to the isocyanides (Table 4). We found that aromatic
isocyanides bearing either electron-withdrawing or electron-
donating groups and 1-isocyanonaphthalene, could react with
methanol to give the corresponding N-arylcarbamates 2p-s in
moderate to high yields. In contrast, substrate 1d with electron-
donating group required longer reaction times and gave
comparatively lower product yield. However, no reaction was
observed when aliphatic isocyanides such as tert-butyl
isocyanide and cyclohexyl isocyanide were used as partners.
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Similarly, the insertion reactions of aromatic isocyanides 1b-d
with piperidine also efficiently underwent, generating the desired
ureas 3g-i in high to excellent yields, respectively.
reaction identified that ethyl 2-methoxyacetate and diethyl
fumarate were generated by the O-H bond of methanol insertion
reaction and self-coupling reaction of ethyl diazoacetate L1,
respectively. These results indicate that ethyl diazoacetate was
consumed in the course of the reaction, and used in excess
versus the Rh metal" in the revised manuscript.
Table 4. Rhodium-Catalyzed reaction of isocyanides 1 with alcohols
or amines.[a,b]
[a] Reaction conditions: 1 (0.2 mmol), alcohols or amines (2.0 mL),
L1 (0.2 mmol), Rh(PPh3)3Cl (0.01 mmol), 60 0C for 1-8 h in open air.
[b] Isolated yields. [c] The reaction was performed in the presence of
12 mol% Rh(PPh3)3Cl at 900C in a sealed tube.
To further probe the mechanisms for formation 2 and 3, some
control experiments were designed and investigated. As a result,
it was found that the reaction of 4-isocyanobiphenyl 1a in dry
MeOH (2.0 mL) did not provide [18O]-2a in the presence of H218O
(2.0 equiv.) under otherwise identical conditions (Scheme 1, a),
suggesting that H2O is not involved in the reaction. In addition,
when the reaction of 1a with methanol was carried out under
nitrogen atmosphere, no desired product 2a was produced and
only (E)-ethyl 3-(biphenyl-4-ylimino)-3-methoxypropanoate 4a
was generated in 35% yield (Scheme 1, b). Meanwhile, to
investigate the effect of O2 on the insertion reaction, we
performed the insertion reaction of 1a with methanol under an
18O2 atmosphere, and expectedly [18O]-2a was obtained in 50%
yield along with the formation of 2a (Scheme 1, c). These results
indicate that molecular oxygen from air participated in the
transformation as the oxidant source. The formation of product
2a was suppressed under the optimized condition in the
presence of 2.0 equiv. of 2,2,6,6-tetramethylpiperidinooxy
(TEMPO) as a radical inhibitor (Scheme 1, d), indicating that a
radical process was involved in the insertion reaction. In addition,
in order to study the role of α-diazocarbonyls in the
transformation, the Rh-catalyzed coupling reaction of 1a with
methanol was performed in the presence of N-heterocyclic
carbene (NHC, 20 mol%) and NaH (40 mol%) in the open air at
60 0C for 12 h. As a result, the desired product 2a was produced
in 63% yield (Scheme 1, e), indicating that α-diazocarbonyl L1
served as carbene precursor to activate the Rh-catalyst in the
reaction. In addition, further GC-MS studies of the model
Scheme 1. Control experiments for mechanistic studies.
On the basis of the above experimental results together with
related reports,[14-17] a possible reaction pathway for the reaction
is proposed in Scheme 2. Initially, Rh(PPh3)3Cl undergoes
insertion reaction with α-diazocarbonyl L1 to give the Rh-
carbene A,[14] which reacts with isocyanide 1 to produce
intermediate B.[15] The intermediate B was oxidated by O2 (from
air), followed by a homolysis of O-O bond to furnish the
intermediate E.[16] Finally, the intermediate E reacts with alcohols
or amines to give desired products 2 or 3 (Scheme 2).[17]
Scheme 2. Proposed mechanisms for the formation of 2 and 3.
Conclusions
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128.70, 127.60, 126.93, 126.72, 118.89, 65.16, 30.95, 19.05, 13.70; HRMS
(ESI-TOF): [M + H]+ calculated for C17H20NO2+: 270.1489, found: 270.1494.
In conclusion, we have developed a novel Rh-catalyzed aerobic
oxidative coupling reaction of isocyanides with various alcohols
or amines. The reaction is conducted in air and employs
molecular oxygen as the terminal oxidant and oxygen-atom
source, providing a simple, general and efficient approach to N-
arylcarbamates and ureas in an atom-economic manner from
readily available starting materials under mild reaction conditions.
Moreover, the novel mechanism involving α-diazocarbonyls as
carbene precursors and Rh(I)/Rh(III) catalytic cycle by a single
electron oxidization process with oxygen might provide a new
model for rhodium chemistry. Further work on the applications
and extension of the novel catalytic system are currently under
investigation in our laboratory.
Propyl [1,1'-biphenyl]-4-ylcarbamate (2d)
Colorless solid (41.8 mg, 82%); mp 152-153 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.57-7.54 (m, 4H), 7.47-7.41 (m, 4H), 7.32 (t, J = 7.5 Hz, 1H), 6.76 (s, 1H),
4.15 (t, J = 6.5Hz, 2H), 1.74-1.68 (m, 2H), 0.99 (t, J = 7.5 Hz, 3H); 13C NMR
(126 MHz, CDCl3) δ = 153.64, 140.42, 137.21, 136.11, 128.65, 127.55,
126.66, 118.84, 66.83, 22.19, 10.27. One carbon is not visible due to
+
overlapping peaks; HRMS (ESI-TOF): [M + Na]+ calculated for C16H17NNaO2
:
278.1151, found: 278.1161.
Isobutyl [1,1'-biphenyl]-4-ylcarbamate (2e)
Colorless solid (39.3 mg, 73%); mp 167-168 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.55 (t, J = 8.5 Hz, 4H), 7.47-7.40 (m, 4H), 7.32 (t, J = 7.5 Hz, 1H) , 6.71 (s,
1H), 3.98 (d, J = 6.5 Hz, 2H), 2.03-1.95 (m, 1H), 0.98 (d, J = 7.0 Hz, 6H); 13C
NMR (126 MHz, CDCl3) δ = 153.60, 140.42, 137.18, 136.12, 128.64, 127.55,
126.87, 126.66, 118.77, 71.34, 27.87, 18.97; HRMS (ESI-TOF): [M + Na]+
calculated for C17H19NNaO2+: 292.1308, found: 292.1303.
Experimental Section
General Information. All reagents were commercial and were used without
further purification. Chromatography was carried on flash silica gel (300-400
mesh). All reactions were monitored by TLC, which was performed on
percolated aluminum sheets of silica gel 60 (F254). Melting points were
uncorrected. Unless noted, the 1H NMR spectra were recorded at 300 MHz,
400 MHz, 500 MHz, 600 MHz in CDCl3 or DMSO-D6 and the 13C NMR spectra
were recorded at 126 MHz, 151 MHz in CDCl3 or DMSO-D6 with TMS as
internal standard. All coupling constants (J values) were reported in Hertz (Hz).
2,2,2-Trifluoroethyl [1,1'-biphenyl]-4-ylcarbamate (2f)
Colorless solid (44.3 mg, 75%); mp 158-159 0C; 1H NMR (500 MHz, DMSO-
D6) δ = 10.24 (s, 1H), 7.64-7.62 (m, 4H), 7.58 (d, J = 8.0 Hz, 2H), 7.43 (t, J =
7.5 Hz, 2H), 7.32, (t, J = 7.5 Hz, 1H), 4.81 (q, J = 9.0 Hz, 2H); 13C NMR (126
MHz, DMSO-D6) δ = 152.14, 140.08, 138.29, 135.34, 129.35, 127.58, 126.73,
125.29, 123.08, 119.30, 60.82, 60.54, 60.26, 59.98; HRMS (ESI-TOF): [M +
H]+ calculated for C15H13F3NO2+: 296.0893, found: 296.0898.
High-resolution mass spectra (HRMS) were obtained using
a Bruker
Phenethyl [1,1'-biphenyl]-4-ylcarbamate (2g)
microTOF II focus spectrometer (ESI). High performance liquid
chromatography (HPLC) analyses were performed on a Shimadzu LC-20AD
Series instrument, using AD-H Columns. UV absorption was monitored at 254
nm.
Colorless solid (50.1 mg, 79%); mp 187-189 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.58-7.53 (m, 4H), 7.44-7.53 (m, 4H), 7.35-7.31 (m, 3H), 7.28-7.35 (m, 3H),
6.70 (s, 1H), 4.42 (t, J = 7.0 Hz, 2H), 3.02 (t, J = 7.0 Hz, 2H); 13C NMR (126
MHz, CDCl3) δ = 153.40, 140.48, 137.73, 137.10, 136.34, 128.88, 128.74,
128.53, 127.64, 126.99, 126.76, 126.59, 118.95, 65.66, 35.37; HRMS (ESI-
TOF): [M + Na]+ calculated for C21H19NNaO2+: 340.1308, found: 340.1312.
General Procedure for the Preparation of 2 (2a as Example). To a solution
of ethyl 4-isocyanobiphenyl 1a (0.2 mmol, 35.8 mg) and ethyl diazoacetate
(0.2 mmol, 0.021 mL) in methanol (2.0 mL) was added Rh(PPh3)3Cl (0.01
mmol, 9.2 mg). The reaction mixture was stirred at 60 0C for 7 h. After 1a was
consumed (monitored by TLC), the reaction mixture was poured into water (50
mL) and extracted with CH2Cl2 (10 mL × 3). The combined organic extracts
were dried over anhydrous Na2SO4, filtered and concentrated under reduced
pressure to yield the corresponding crude product, which was purified by
chromatography (silica gel, petroleum ether/acetone = 10/1, V/V) to give 2a.
2-(Thiophen-2-yl)ethyl [1,1'-biphenyl]-4-ylcarbamate (2h)
Colorless solid (46.5 mg, 72%); mp 164-165 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.58-7.54 (m, 4H), 7.46-7.41 (m, 4H), 7.33 (t, J = 7.5 Hz, 1H), 7.17 (d, J =
10.0 Hz, 1H), 6.98-6.96 (m, 1H), 6.91 (d, J = 3.0 Hz, 1H), 6.76 (s, 1H), 4.43 (t,
J = 8.5 Hz, 2H), 3.23 (t, J = 6.5 Hz, 2H); 13C NMR (126 MHz, CDCl3) δ =
153.24, 140.45, 139.88, 137.02, 136.39, 128.73, 127.64, 126.99, 126.90,
126.75, 125.52, 124.01, 118.95, 65.40, 29.60; HRMS (ESI-TOF): [M + H]+
calculated for C19H18NO2S+: 324.1053, found: 324.1058.
Methyl [1,1'-biphenyl]-4-ylcarbamate (2a)
Colorless solid (39.5 mg, 87%); mp 141-143 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.57-7.54 (m, 4H), 7.47-7.41 (m, 4H), 7.32 (t, J = 9.5 Hz, 1H), 6.67 (s, 1H),
3.80 (s, 3H); 13C NMR (126 MHz, CDCl3) δ = 153.98, 140.51, 137.13, 136.42,
128.75, 127.69, 127.01, 126.78, 118.99, 52.39; HRMS (ESI-TOF): [M + Na]+
calculated for C14H13NNaO2+: 250.0838, found: 250.0833.
But-3-yn-1-yl [1,1'-biphenyl]-4-ylcarbamate (2i)
Colorless solid (42.4 mg, 80%); mp 158-159 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.57-7.54 (m, 4H), 7.46-7.41 (m, 4H), 7.32(t, J = 8.0 Hz, 1H), 6.76 (s, 1H),
4.30 (t, J = 6.5 Hz, 2H), 2.62-2.59 (m, 2H), 2.04 (t, J = 2.5 Hz, 1H); 13C NMR
(126 MHz, CDCl3) δ = 153.03, 140.44, 136.91, 136.49, 128.73, 127.68,
Ethyl [1,1'-biphenyl]-4-ylcarbamate (2b)
126.76, 118.93, 80.19, 69.95, 62.94. Two carbons are not visible due to
+
overlapping peaks; HRMS (ESI-TOF): [M + Na]+ calculated for C17H15NNaO2
:
Colorless solid (39.1 mg, 81%); mp 157-158 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.57-7.53 (m, 4H), 7.46-7.40 (m, 4H), 7.34-7.30 (m, 1H), 6.72 (s, 1H), 4.24
(q, J = 9.0 Hz, 2H), 1.32 (t, J = 8.5 Hz, 3H); 13C NMR (126 MHz, CDCl3) δ =
153.59, 140.53, 137.27, 136.26, 128.73, 127.65, 126.75, 118.95, 61.28, 14.54.
One carbon is not visible due to overlapping peaks; HRMS (ESI-TOF): [M +
Na]+ calculated for C15H15NNaO2+: 264.0995, found: 264.0991.
288.0995, found: 288.0987.
Benzyl [1,1'-biphenyl]-4-ylcarbamate (2j)
Colorless solid (43.6 mg, 72%); mp 174-176 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.58-7.54 (m, 4H), 7.48-7.32 (m, 10H), 6.78 (s, 1H), 5.23 (s, 2H); 13C NMR
(126 MHz, CDCl3) δ = 153.29, 140.46, 137.04, 136.41, 135.98, 128.73,
127.66, 126.76, 118.96, 67.08. Four carbons are not visible due to overlapping
peaks; HRMS (ESI-TOF): [M + Na]+ calculated for C20H17NNaO2+: 326.1151,
found: 326.1151.
Butyl [1,1'-biphenyl]-4-ylcarbamate (2c)
Colorless solid (43.6 mg, 81%); mp 153-154 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.59-7.55 (m, 4H), 7.45-7.42 (m, 4H), 7.33 (t, J = 7.5 Hz, 1H), 6.77 (s, 1H),
4.21 (t, J = 6.5 Hz, 2H), 1.72-1.47 (m, 2H), 1.46-1.41 (m, 2H), 0.98 (t, J = 7.5
Hz, 3H); 13C NMR (126 MHz, CDCl3) δ = 153.71, 140.49, 137.28, 136.17,
Furan-2-ylmethyl [1,1'-biphenyl]-4-ylcarbamate (2k)
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Colorless solid (41.6 mg, 71%); mp 149-151 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.55 (t, J = 7.5 Hz, 4H), 7.43 (dd, J = 8.0, 7.5 Hz, 5H), 7.32 (t, J = 7.5 Hz,
1H), 6.48 (s, 1H), 6.47 (d, J = 3.5 Hz, 1H), 6.39 (dd, J = 7.0, 8.5 Hz, 1H), 5.18
(s, 2H); 13C NMR (126 MHz, CDCl3) δ = 152.93, 149.51, 143.38, 140.46,
136.92, 136.52, 128.75, 127.70, 127.02, 126.78, 118.95, 110.81, 110.64,
58.76; HRMS (ESI-TOF): [M + H]+ calculated for C18H16NO3+: 294.1125, found:
294.1130.
126.29, 126.05, 125.82, 125.21, 120.56, 52.63. Two carbons are not visible
due to overlapping peaks; [M + H]+ calculated for C12H12NO2+: 201.0863,
found: 201.0867.
General Procedure for the Preparation of 3 (3a as Example). To a
solution of 4-isocyanobiphenyl 1a (0.2 mmol, 35.8 mg) and ethyl diazoacetate
(0.2 mmol, 0.021 mL) in diethylamine (2.0 mL) was added Rh(PPh3)3Cl (0.01
mmol, 9.2 mg). The reaction mixture was stirred at 60 0C for 1 hour. After 1a
was consumed (monitored by TLC), the reaction mixture was poured into
water (50 mL) and extracted with CH2Cl2 (10 mL × 3). The combined organic
extracts were dried over anhydrous Na2SO4, filtered and concentrated under
reduced pressure to yield the corresponding crude product, which was purified
by chromatography (silica gel, petroleum ether/acetone = 5/1, V/V) to give 3a.
Cyclohexyl [1,1'-biphenyl]-4-ylcarbamate (2l)
Colorless solid (38.4 mg, 65%); mp 155-157 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.57-7.53 (m, 4H), 7.46-7.40 (m, 4H), 7.32 (t, J = 7.5 Hz, 1H), 6.64 (s, 1H),
4.79-4.76 (m, 1H), 1.96-1.95 (m, 2H), 1.78-1.76 (m, 2H), 1.59-1.56 (m, 1H),
1.52-1.38 (m, 4H), 1.32-1.27 (m, 1H); 13C NMR (126 MHz, CDCl3) δ = 153.14,
140.56, 137.44, 136.09, 128.72, 127.63, 126.74, 118.83, 73.73, 31.92, 25.37,
23.78. One carbon is not visible due to overlapping peaks; HRMS (ESI-TOF):
[M + H]+ calculated for C19H22NO2+: 296.1645, found: 296.1651.
3-([1,1'-Biphenyl]-4-yl)-1,1-diethylurea (3a)
Yellow liquid (43.4 mg, 81%); 1H NMR (500 MHz, CDCl3) δ = 7.60-7.58 (m,
3H), 7.52-7.50 (m, 2H), 7.41 (t, J = 9.5 Hz, 2H), 7.29 (t, J = 8.0 Hz, 1H), 7.03
Isopropyl [1,1'-biphenyl]-4-ylcarbamate (2m)
Colorless solid (37.2 mg, 73%); mp 161-163 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.55 (t, J = 8.5 Hz, 4H), 7.47-7.40 (m, 4H), 7.32 (t, J = 7.5 Hz, 1H), 6.71 (s,
1H), 5.01-5.06 (m, 1H), 1.32 (d, J = 6.5 Hz, 6H); 13C NMR (126 MHz, CDCl3) δ
= 153.18, 140.53, 137.39, 136.10, 128.71, 127.61, 126.73, 118.64, 68.80,
22.08. One carbon is not visible due to overlapping peaks; HRMS (ESI-TOF):
[M + Na]+ calculated for C16H17NNaO2+: 278.1151, found: 278.1148.
(q, J = 2.5, 6.0 Hz, 2H), 3.51 (s, 2H), 3.33 (s, 2H), 1.23 (t, J = 9.0 Hz, 6H); 13
C
NMR (126 MHz, CDCl3) δ = 152.19, 141.08, 135.18, 130.84, 128.58, 127. 61,
126.60, 126.46, 121.35, 45.71, 39.53, 14.98, 12.43; HRMS (ESI-TOF): [M +
H]+ calculated for C17H21N2O+: 269.1648, found: 269.1645.
N-([1,1'-Biphenyl]-4-yl)piperidine-1-carboxamide (3b)
Yellow liquid (53.2 mg, 95%); 1H NMR (500 MHz, CDCl3) δ = 7.61-7.57 (m,
3H), 7.53 (d, J = 8.5 Hz, 2H), 7.42 (t, J = 8.0 Hz, 2H), 7.31 (t, J = 1.5 Hz, 1H),
7.30-7.04 (m, 2H), 3.45-3.49 (m, 4H), 1.70 (m, 2H), 1.66-1.61 (m, 4H); 13C
NMR (126 MHz, CDCl3) δ = 152.58, 151.53, 141.16, 135.12, 128.64, 127.66,
126.64, 126.49, 121.38, 50.83, 42.76, 24.73; HRMS (ESI-TOF): [M + H]+
calculated for C18H21N2O+: 281.1648, found: 281.1657.
(S)-3,7-Dimethyloct-6-en-1-yl [1,1'-biphenyl]-4-ylcarbamate (2o)
Colorless solid (42.1 mg, 60%); mp 188-189 0C; 1H NMR (500 MHz, CDCl3) δ
= 7.57-7.53 (m, 4H), 7.46-7.40 (m, 4H), 7.31 (t, J = 7.5 Hz, 1H), 6.66 (s, 1H),
5.10 (t, J = 7.0 Hz, 1H), 4.25-4.19 (m, 2H), 2.04 (m, 2H), 1.73-1.71 (m, 1H),
1.68 (s, 3H), 1.51-1.49 (m, 3H), 1.38-1.39 (m, 1H), 1.26-1.25 (m, 1H), 1.24-
1.20 (m, 2H), 0.95 (d, J = 7.0 Hz, 3H); 13C NMR (126 MHz, CDCl3) δ = 153.43,
140.50, 137.25, 136.21, 131.34, 128.71, 127.63, 126.94, 126.73, 124.52,
118.86, 63.85, 36.99, 35.76, 29.41, 25.69, 25.38, 19.38, 17.63; 97% ee was
determined by HPLC analysis [Daicel Chiralpak AD-H, Hexanes/Propanol =
98/2, 1.0 ml/min, λ = 254 nm, t (major) = 24.68 min, t(minor) = 26.25
min];HRMS (ESI-TOF): [M + H]+ calculated for C23H30NO2+: 352.2271, found:
352.2281.
N-([1,1'-Biphenyl]-4-yl)-3,5-dimethylpiperidine-1-carboxamide (3c)
Yellow solid (57.3 mg, 93%); mp 157-159 0C; 1H NMR (500 MHz, CDCl3) δ =
7.63-7.54 (m, 5H), 7.43 (t, J = 7.0 Hz, 2H), 7.31 (t, J = 7.5 Hz, 1H), 7.07 (d, J =
8.5 Hz, 2H), 4.52 (s, 1H), 3.40 (s, 1H), 2.60 (s, 1H), 2.34 (s, 1H), 1.87 (d, J =
13.0 Hz, 1H), 1.69 (s, 2H), 0.95 (d, J = 6.0 Hz, 6H), 0.83 (q, J = 12.0 Hz, 1H);
13C NMR (126 MHz, CDCl3) δ = 152.28, 151.53, 141.15, 135.11, 128.66,
127.65, 126.64, 126.52, 121.43, 56.94, 49.52, 42.55, 32.37, 30.68, 19.01;
HRMS (ESI-TOF): [M + H]+ calculated for C20H25N2O+: 309.1961, found:
309.1965.
Methyl (4-chlorophenyl)carbamate (2p)
Orange solid (33.3 mg, 90%); 1H NMR (500 MHz, DMSO-D6) δ = 9.79 (s,
1H), 7,48 (d, J = 9.0 Hz, 2H), 7.33 (t, J = 2.0 Hz, 2H), 3.67 (s, 3H); 13C NMR
(126 MHz, DMSO-D6) δ = 154.42, 138.67, 139.13, 136.48, 120.11, 52.24;
HRMS (ESI-TOF): [M + H]+ calculated for C8H9ClNO2+: 186.0316, found:
186.0322. Spectral data match those previously reported.[18]
N-([1,1'-Biphenyl]-4-yl)morpholine-4-carboxamide (3d)
Yellow solid (52.5 mg, 93%); mp 157-158 0C; 1H NMR (500 MHz, CDCl3) δ =
7.62 (d, J = 7.5 Hz, 2H), 7.56 (d, J = 7.5 Hz, 3H), 7.44 (t, J = 7.5 Hz, 2H), 7.32
(t, J = 7.5 Hz, 1H), 7.07 (d, J = 8.5 Hz, 2H), 3.73 (t, J = 5 Hz, 4H), 3.51 (s, 4H);
13C NMR (126 MHz, CDCl3) δ = 152.20, 150.84, 140.97, 135.62, 128.74,
127.73, 126.70, 126.67, 121.45, 66.65; HRMS (ESI-TOF): [M + H]+ calculated
for C17H19N2O2+: 283.1441, found: 283.1446.
Methyl (4-bromophenyl)carbamate (2q)
Colorless solid (41.7 mg, 91%); 1H NMR (500 MHz, DMSO-D6) δ = 9.79 (s,
1H), 7.46-7.41 (m, 4H), 3.66 (s, 3H); 13C NMR (126 MHz, DMSO-D6) δ =
154.39, 139.10, 132.03, 120.52, 114.41, 52.25; HRMS (ESI-TOF): [M + H]+
calculated for C8H9BrNO2+: 229.9811, found: 229.9817. Spectral data match
those previously reported.[18]
N-([1,1'-Biphenyl]-4-yl)pyrrolidine-1-carboxamide (3e)
Yellow liquid (49.5 mg, 93%); 1H NMR (600 MHz, CDCl3) δ = 7.79 (s, 1H),
7.58 (t, J = 8.4 Hz, 2H), 7.50-7.49 (m, 2H), 7.38 (t, J = 7.2 Hz, 2H), 7.26 (t, J =
7.2 Hz, 1H), 7.03 (t, J = 8.4 Hz, 2H), 3.48 (s, 4H), 1.90 (s, 4H); 13C NMR (151
MHz, CDCl3) δ = 150.85, 150.43, 141.19, 135.09, 128.71, 127.69, 126.67,
126.55, 121.57, 48.84, 45.36, 25.06; [M + H]+ calculated for C17H19N2O+:
267.1492, found: 267.1491.
Methyl (4-methoxyphenyl)carbamate (2r)
Colorless solid (16.3 mg, 45%); 1H NMR (500 MHz, CDCl3) δ = 7.26 (d, J =
5.0 Hz, 2H), 6.85- 6.83 (m, 2H), 6.57 (s, 1H), 3.77 (s, 3H), 3.74 (s, 3H); 13C
NMR (126 MHz, CDCl3) δ = 155.99, 154.51, 130.62, 120.66, 114.22, 55.47,
52.24; HRMS (ESI-TOF): [M + H]+ calculated for C9H12NO3+: 182.0812, found:
182.0817. Spectral data match those previously reported.[19]
1,1-Diallyl-3-(biphenyl-4-yl)urea (3f)
Yellow liquid (51.4 mg, 88%); 1H NMR (500 MHz, CDCl3) δ = 7.68 (s, 1H),
7.64-7.62 (m, 2H), 7.57-7.55 (m, 2H), 7.45 (t, J = 7.5 Hz, 2H), 7.33 (t, J = 6.0
Hz, 1H), 7.09 (d, J = 8.5 Hz, 2H), 5.88, (s, 2H), 5.25 (d, J = 8.5 Hz, 4H), 4.17
(s, 2 H), 3.85 (s, 2H); 13C NMR (126 MHz, CDCl3) δ = 152.55, 151.30, 141.13,
135.40, 133.87, 132.99, 128.68, 127.67, 126.68, 126.57, 121.53, 117.69,
Methyl naphthalen-1-ylcarbamate (2s)
Colorless solid (30.2 mg, 75%); mp 185-187 0C; 1H NMR (300 MHz, CDCl3)
δ = 7.91-7.88 (m, 3H), 7.70 (d, J = 8.4 Hz, 1H), 7.55-7.47 (m, 3H), 7.02 (s, 1H),
3.85 (s, 3H); 13C NMR (126 MHz, CDCl3) δ = 155.06, 134.12, 132.51, 128.75,
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52.56, 47.26; HRMS (ESI-TOF): [M + H]+ calculated for C19H21N2O+: 293.1648,
found: 293.1655.
[1] For recent reviews, see: a) Isocyanide Chemistry Applications in Synthesis
and Materials Science (Ed.: V. Nenajdenko), Wiley-VCH, Weinheim, 2012;
b) V. G. Nenajdenko, Isocyanide Chemistry, Wiley-VCH, Weinheim, 2012;
c) S. Chakrabarty, S. Choudhary, A. Doshi, F.-Q. Liu, R. Mohan, M. P.
Ravindra, D. Shah, X. Yang, F. F. Fleming, Adv. Synth. Catal. 2014, 356,
2315.
N-(4-Chlorophenyl)piperidine-1-carboxamide (3g)
Colorless solid (44.3 mg, 93%); 1H NMR (500 MHz, CDCl3) δ = 7.45 (s, 1H),
7.32 (d, J = 7.5 Hz, 2H), 6.81 (d, J = 7.5 Hz, 2H), 3.54 (s, 2H), 3.32 (s, 2H),
1.68-1.65 (m, 2H), 1.62-1.57 (m, 4H); 13C NMR (126 MHz, CDCl3) δ = 152.56,
151.27, 131.80, 122.72, 114.91, 50.40, 43.41, 24.65; HRMS (ESI-TOF): [M +
H]+ calculated for C12H16ClN2O+: 239.0946, found: 239.0947. Spectral data
match those previously reported.[20]
[2] a) J. Zhu, H. Bienayme, Multicomponent Reactions, Wiley-VCH, Weinheim,
2005; b) A. Dömling, Chem. Rev. 2006, 106, 17; c) L. Banfi, R. Riva, in
Organic Reactions, Vol. 65 (Ed.: A. B. Charette), Wiley, New York, 2005,
pp. 1; d) A. Döling, I. Ugi, Angew. Chem. 2000, 112, 3300; Angew. Chem.
Int. Ed. 2000, 39, 3168.
N-(4-Bromophenyl)piperidine-1-carboxamide (3h)
[3] a) D. V. Leusen, A. M. V. Leusen, Org. React. 2001, 57, 417; b) A. V.
Gulevich, A. G. Zhdanko, R. V. A. Orru, V. G. Nenajdenko, Chem. Rev.
2010, 110, 5235.
Colorless solid (53.6 mg, 95%); mp 176-178 0C; 1H NMR (500 MHz, CDCl3)
δ = 7.45 (s, 1H), 7.18 (d, J = 7.5 Hz, 2H), 6.86 (d, J = 9.0 Hz, 2H), 3.52 (s, 2H),
3.33 (s, 2H), 1.66 (m, 2H), 1.59 (m, 4H); 13C NMR (126 MHz, CDCl3) δ =
152.62, 150.79, 128.85, 127.27, 122.21, 50.12, 43.21, 24.65; HRMS (ESI-
TOF): [M + H]+ calculated for C12H16BrN2O+: 283.0441, found: 283.0443.
[4] For a review, see: B. Zhang, S. Armido, Chem. Soc. Rev. 2015, 44, 3505.
[5] For reviews, see: a) G. Qiu, Q. Ding, J. Wu, Chem. Soc. Rev. 2013, 42,
5257; b) V. P. Boyarskiy, N. A. Bokach, K. V. Luzyanin, V. Y. Kukushkin,
Chem. Rev. 2015, 115, 2698; c) S. Lang, Chem. Soc. Rev. 2013, 42,
4867.; d) T. Vlaar, E. Ruijter, B. U. W. Maes, R. V. A. Orru, Angew. Chem.
2013, 125, 7222; Angew. Chem., Int. Ed. 2013, 52, 7084; e) A. V. Lygin, A.
de Meijere, Angew. Chem. 2010, 122, 9280; Angew. Chem., Int. Ed. 2010,
49, 9094; f) M. Tobisu, N. Chatani, Chem. Lett. 2011, 40, 330.
N-(4-Methoxyphenyl)piperidine-1-carboxamide (3i)
Colorless solid (41.7 mg, 89%); 1H NMR (300 MHz, CDCl3) δ = 7.48 (s, 1H),
6.91 (dd, J = 2.1, 6.6 Hz, 2H), 6.83 (dd, J = 2.1, 6.6 Hz, 2H), 3.79 (s, 3H), 3.44
(s, 4H), 1.69-1.58 (m, 6H); 13C NMR (126 MHz, CDCl3) δ = 155.30, 152.75,
[6] For selected recent reports, see: a) W. Kong, Q. Wang, J. Zhu, Angew.
Chem. 2016, 128, 9866; Angew. Chem. Int. Ed. 2016, 55, 9714; b) S. Tong,
Q. Wang, M. X. Wang, J. Zhu, Angew. Chem. 2015, 127, 1309; Angew.
Chem. Int. Ed. 2015, 54, 1293; c) M. C. Lipke, A. L. Liberman-Martin, T. D.
Tilley, J. Am. Chem. Soc. 2016, 138, 9704; d) W.-J. Kong, Y.-J. Liu, H. Xu,
Y.-Q. Chen, H.-X. Dai, J.-Q. Yu, J. Am. Chem. Soc. 2016, 138, 2146; e) S.
Tong, Q. Wang, M.-X. Wang, J. Zhu, Chem. Eur. J. 2016, 22, 8332; f) Y.
Tian, L. Tian, C. Li, X. Jia, J. Li, Org. Lett. 2016, 18, 840; g) Y. Tian, L. Tian,
X. He, C. Li, X. Jia, J. Li, Org. Lett. 2015, 17, 4874; h) Y. Liu, H. Xu,W.
Kong, M. Shang, H. Dai, J. Yu, Nature 2014, 515, 389; i) M. Tobisu, K. Koh,
T. Furukawa, N. Chatani, Angew. Chem. 2012, 124, 11525; Angew. Chem.
Int. Ed. 2012, 51, 11363; j) H. Jiang, Y. Cheng, R. Wang, M. Zheng, Y.
Zhang, S. Yu, Angew. Chem. 2013, 125, 13531; Angew. Chem. Int. Ed.
2013, 52, 13289; k) C. Kanazawa, S. Kamijo, Y. Yamamoto, J. Am. Chem.
Soc. 2006, 128, 10662.
145.66, 121.68, 114.35, 55.54, 29.93, 25.82, 24.78; [M + H]+ calculated for
+
C13H19N2O2
:
235.1441, found: 235.1444. Spectral data match those
21]
previously reported.[
General Procedure for the Preparation of (4a): To a solution of 4-
isocyanobiphenyl 1a (0.2 mmol, 35.8 mg) and ethyl diazoacetate (0.2 mmol,
0.021 mL) in methanol (2 mL) was added Rh(PPh3)3Cl (0.01 mmol, 9.2 mg) at
N2 atmosphere. The reaction mixture was stirred at 60 0C for 7 h. Then the
reaction mixture was poured into water (50 mL) and extracted with CH2Cl2 (10
mL × 3). The combined organic extracts were dried over anhydrous Na2SO4,
filtered and concentrated under reduced pressure to yield the corresponding
crude product, which was purified by chromatography (silica gel, petroleum
ether/ ether = 10/1, V/V) to give 4a.
[7] a) X. Huang, S. Xu, Q. Tan, M. Gao, M. Li, B. Xu, Chem. Commun. 2014,
50, 1465; b) T.-H. Zhu, X.-P. Xu, J.-J. Cao, T.-Q. Wei, S.-Y. Wang, S.-J. Ji,
Adv. Synth. Catal. 2014, 356, 509; c) F. Zhou, K. Ding, Q. Cai, Chem. Eur.
J. 2011, 17, 12268; d) E. R. Klobukowski, R. J. Angelici, L. K. Woo,
Organometallics 2012, 31, 2785.
(E)-Ethyl 3-(biphenyl-4-ylimino)-3-methoxypropanoate (4a)
Yellow liquid (20.8 mg, 35%); 1H NMR (600 MHz, CDCl3) δ = 7.58-7.57 (m,
2H), 7.53-7.52 (m, 2H), 7.43-7.40 (m, 2H), 7.31 (t, J = 7.2 Hz, 1H), 6.88 (d, J =
8.4 Hz, 2H), 4.16 (q, J = 7.2 Hz, 2H), 3.87 (s, 3H), 3.26 (s, 2H), 1.25 (t, J = 7.2
Hz, 3H); 13C NMR (151 MHz, CDCl3) δ = 167.81, 157.16, 147.36, 140.82,
136.35, 128.74, 127.78, 126.90, 126.78, 121.48, 61.39, 53.86, 36.38, 14.08;
[M + H]+ calculated for C18H20NO3+: 298.1438, found: 298.1427.
[8] a) T. Punniyamurthy, S. Velusamy, J. Iqbal, Chem. Rev. 2005, 105, 2329;
b) S. S. Stahl, Angew. Chem. 2004, 116, 3480; Angew. Chem., Int. Ed.
2004, 43, 3400; c) M. S. Sigman, D. R. Jensen, Acc. Chem. Res. 2006, 39,
221; d) K. M. Gligorich, M. S. Sigman, Angew. Chem. 2006, 118, 6764;
Angew. Chem., Int. Ed. 2006, 45, 6612; e) Z. Shi, C. Zhang, C. Tang, N.
Jiao, Chem. Soc. Rev. 2012, 41, 3381; f) S. E. Allen, R. R. Walvoord, R.
Padilla-Salinas, M. C. Kozlowski, Chem. Rev. 2013, 113, 6234; g) D. J. C.
Constable, P. J. Dunn, J. D. Hayler, G. R. Humphrey, J. J. L. Leazer, R. J.
Linderman, K. Lorenz, J. Manley, B. A. Pearlman, A. Wells, A. Zaks, T. Y.
Zhang, Green Chem. 2007, 9, 411; h) D. T. Sawyer, Oxygen chemistry,
Oxford University Press, 1991.
Acknowledgements
Financial supports of this research by the National Natural
Sciences Foundation of China (21472017), Natural Sciences
Foundation of Jilin Province (20150101065JC), Fundamental
Research Funds for the Central Universities and Thirteenth Five-
Year Sci-Tech Research Guideline of the Education Department
of Jilin Province are greatly acknowledged.
[9] a) T. Vlaar, R. C. Cioc, P. Mampuys, B. U. W. Maes, R. V. A. Orru, E.
Ruijter, Angew. Chem. 2012, 124, 13235; Angew. Chem. Int. Ed. 2012, 51,
13058; b) T.-H. Zhu, S.-Y. Wang, Y.-Q. Tao, T.-Q. Wei, S.-J. Ji, Org. Lett.
2014, 16, 1260; c) Y. Wang, H. Wang, J. Peng, Q. Zhu, Org. Lett. 2011, 13,
4604; d) Z. Hu, D. Liang, J. Zhao, J. Huang, Q. Zhu, Chem. Commun.
2012, 48, 7371.
[10] J. Liu, Z. Liu, P. Liao, L. Zhang, T. Tu, X. Bi, Angew. Chem. 2015, 127,
10764; Angew. Chem. Int. Ed. 2015, 54, 10618.
Keywords: rhodium catalysis • isocyanides • oxidative insertion
• N-arylcarbamates • ureas
[11] For selected recent reports, see: a) L. Li, Y.-L. Zhao, Q. Wang, T. Lin, Q.
Liu, Org. Lett. 2015, 17, 370; b) Y. Dong, B. Liu, P. Chen, Q. Liu, M. Wang,
Angew. Chem. 2014, 126, 3510; Angew. Chem. Int. Ed. 2014, 53, 3442; c)
H. Wang, Y.-L. Zhao, L. Li, S.-S. Li, Q. Liu, Adv. Synth. Catal. 2014, 356,
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3157; d) L. Li, Y.-L. Zhao, H. Wang, Y.-J. Li, X. Xu, Q. Liu, Chem. Commun.
2014, 50, 645.
[16] For reviews, see: a) J. T. Mague, G. Wilkinson, J. Chem. SOC. (A), 1966,
1736; b) G. Song, F. Wang, X. Li, Chem. Soc. Rev. 2012, 41, 3651; c) J.
Wencel-Delord, T. Droge, F. Liu, F. Glorius, Chem. Soc. Rev. 2011, 40,
4740; d) . uhl, . Schr der, F. Glorius, Adv. Synth. Catal. 2014, 356,
1443; e) D. A. Colby, R. G. Bergman, J. A. Ellman, Chem. Rev. 2010, 110,
[12] a) Z. Hu, H. Yuan, Y. Men, Q. Liu, J. Zhang, X. Xu, Angew. Chem. 2016,
128, 7193; Angew. Chem. Int. Ed. 2016, 55, 7077; b) X. Xu, L. Zhang, X.
Liu, L. Pan, Q. Liu, Angew. Chem. 2013, 125, 9441; Angew. Chem. Int. Ed.
2013, 52, 9271; c) H. Wang, Y-L. Zhao, C.-Q. Ren, A. Diallo, Q. Liu, Chem.
Commun. 2011, 47, 12316; d) J. Tan, X. Xu, L. Zhang, Y. Li, Q. Liu, Angew.
Chem. 2009, 121, 2912; Angew. Chem. Int. Ed. 2009, 48, 2868.
[13] a) L. Li, J.-J. Chen, Y.-J. Li, X.-B. Bu, Q. Liu, Y.-L. Zhao, Angew. Chem.
2015, 127, 12275; Angew. Chem. Int. Ed. 2015, 54, 12107; b) Y.-J. Li, X. Li,
S.-X. Zhang, Y.-L. Zhao, Q. Liu, Chem. Commun. 2015, 51, 11564; c) H.
Wang, Y.-L. Zhao, L. Li, Z.-W. Zhang, Q. Liu, Adv. Synth. Catal. 2013, 355,
1540.
624.
[17] a) R. A. Ivanovich, J.-F. Vincent-Rocan, E. B. Elkaeed, A. M. Beauchemin,
Org. Lett. 2015, 17, 4898; b) S, Sivakamasundari, R. Ganesan, J. Org.
Chem. 1984, 49, 720.
[18] E. Kianmehr, M. H. Baghersad, Adv. Synth. Catal. 2011, 353, 2599.
[19] P. Gogoi, D. Konwar, Tetrahedron Lett. 2007, 48, 531.
[20] K. Orito, A. Horibata, T. Nakamura, H. Ushito, H. Nagasaki, M. Yuguchi, S.
Yamashita, T. Yamazaki, M. Tokuda, J. Org. Chem. 2006, 71, 5951.
[21] B. Thavonekham, Synthesis 1997, 1189.
[14] a) D. Chen, D.-X. Zhu, M.-H. Xu, J. Am. Chem. Soc. 2016, 138, 1498; b)
D. Chen, X. Zhang, W.-Y. Qi, B. Xu, M.-H. Xu, J. Am. Chem. Soc. 2015,
137, 5268; c) C. Werlé, R. Goddard, P. Philipps, C. Farès, A. Fürstner, J.
Am. Chem. Soc. 2016, 138, 3797.
[15] S. Orsuka, A. Nakamura, Y. Tatsuno, Chem. Commun. 1967, 836.
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Entry for the Table of Contents (Please choose one layout)
Layout 2:
COMMUNICATION
X.-B. Bu, Z. Wang, Y.-H. Wang, T. Jiang,*
L. Zhang, and Y.-L. Zhao*
Page No. – Page No.
Rhodium-Catalyzed Oxidative
Coupling
Isocyanides with Alcohols or
Amines Using Molecular
Oxygen as Oxygen Source:
Synthesis of Carbamates and
Ureas
Reaction
of
A novel Rh-catalyzed oxidative coupling reaction of isocyanides with alcohols or amines
employing air as the terminal oxidant and oxygen-atom source has been developed. The
reaction provides a simple and efficient method for the construction of N-arylcarbamates
and ureas in an atom-economic manner. A new mechanism involving α-diazocarbonyls
as carbene precursors and Rh(I)/Rh(III) catalytic cycle by a single electron oxidization
process with oxygen is proposed on the basis of experimental studies.
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