CoPc/Cu(OAc)2-catalyzed N-arylation of amines with arylhydrazines leading to N-aryl amines

Article abstract of DOI:10.1016/j.tet.2016.08.058

The N-arylation of amines with arylhydrazines has been developed, achieving the selective cross-coupling of aryl radicals with amines to form N-aryl amines. The reaction uses air as an oxidant, CoPc and Cu(OAc)₂as catalysts. The reaction proceeds under mild conditions in air through a relay process, arylhydrazines are oxidized to aryldiazenes by CoPc, further oxidized to aryl radicals by air (O₂), which are trapped by Cu(OAc)₂–amine complex, followed by reduction–elimination reaction to form N-aryl amines. Arylamines and arylhydrazines give the highest yields, but N-aryl-N-alkylamines and N-alkylamines can be used as well.

Full text of DOI:10.1016/j.tet.2016.08.058

Accepted Manuscript
CoPc/Cu(OAc) -catalyzed N-arylation of amines with arylhydrazines leading to N-aryl
2
amines
Wang-Bin Sun, Pei-Zhi Zhang, Tao Jiang, Cheng-Kun Li, Li-Tao An, Adedamola
Shoberu, Jian-Ping Zou
PII:
S0040-4020(16)30843-2
10.1016/j.tet.2016.08.058
TET 28039
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 14 June 2016
Revised Date: 17 August 2016
Accepted Date: 20 August 2016
Please cite this article as: Sun W-B, Zhang P-Z, Jiang T, Li C-K, An L-T, Shoberu A, Zou J-P, CoPc/
Cu(OAc) -catalyzed N-arylation of amines with arylhydrazines leading to N-aryl amines, Tetrahedron
2
(2016), doi: 10.1016/j.tet.2016.08.058.
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CoPc/Cu(OAc)2-catalyzed N-arylation of amines with
arylhydrazines leading to N-aryl amines
Leave this area blank for abstract info.
Wang-Bin Sun,a Pei-Zhi Zhang,a Tao Jiang,a Cheng-Kun Li, a
Li-Tao An,b Adedamola Shoberu,a Jian-Ping Zou*a, c
a Key Laboratory of Organic Synthesis of Jiangsu Province,,College of Chemistry and Chemical Engineering,
Soochow University, 199 Renai Street, Suzhou, Jiangsu 215123, China.
b College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huaian, 111 West Changjiang
Road, Huai’an, Jiangsu, China, 223300.
c Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry,
Chinese Academy of Sciences, Shanghai 200032, China.

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1
Tetrahedron
journal homepage: www.elsevier.com
CoPc/Cu(OAc)2-catalyzed N-arylation of amines with arylhydrazines leading to N-
aryl amines
Wang-Bin Sun,a Pei-Zhi Zhang,a Tao Jiang,a Cheng-Kun Li, a Li-Tao An,b Adedamola Shoberu,a Jian-Ping
Zou*a, c
a Key Laboratory of Organic Synthesis of Jiangsu Province,,College of Chemistry and Chemical Engineering, Soochow University, 199 Renai Street, Suzhou,
Jiangsu 215123, China.
b
College of Chemistry and Chemical Engineering, Huaiyin Normal University, Huaian, 111 West Changjiang Road, Huai’an, Jiangsu, China, 223300.
Key Laboratory of Synthetic Chemistry of Natural Substances, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, Shanghai 200032,
c
China.
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
The N-arylation of amines with arylhydrazines has been developed, achieving the selective
cross-coupling of aryl radicals with amines to form N-aryl amines. The reaction uses air as an
oxidant, CoPc and Cu(OAc)2 as catalysts. The reaction proceeds under mild conditions in air
through a relay process, arylhydrazines are oxidized to aryldiazenes by CoPc, further oxidized to
aryl radicals by air (O2), which are trapped by Cu(OAc)2−amine complex, followed by
reduction-elimination reaction to form N-aryl amines. Arylamines and arylhydrazines give the
highest yields, but N-aryl-N-alkylamines and N-alkylamines can be used as well.
Available online
Keywords:
2016 Elsevier Ltd. All rights reserved
.
Keyword_1 arylation
Keyword_2 amine
Keyword_3 CoPc
Keyword_4 catalysis
1. Introduction
precursors since they are easily oxidized by various oxidants to
yield aryl radicals; these radicals can then react with alkenes,
arenes, heteroarenes and C60 to form C−C bonds. Inspired by
this, we further investigated the possibility of catalytic C−N bond
formation. Herein we report CoPc/Cu(OAc)2-catalyzed N-
arylation of amines with arylhydrazines using air as a sole
oxidant for N-aryl amines synthesis.
Diarylamines are ubiquitous core structures found in natural
products, pharmaceuticals, agrochemicals, dyes and materials.1
One of the most earliest approach towards preparing
diarylamines2 is the Ullmann reaction which was reported in
early 1900’s. Significant improvements on this approach has
been described afterwards in literature.3 Since Buchwald and
Hartwig reported the Pd-catalyzed aromatic C-N bond-forming
reaction, tremendous progress has been made in the area of
transition-metal catalyzed N-arylation of arylamines.4 Another
important route to diarylamines is the reaction of anilines or
aniline surrogates with stoichiometric arylmetal species or excess
of hypervalent iodine reagents.5 Other methods include the
polyphosphoric acid-mediated reaction of nitroalkanes with
arenes,6 PhI(OAc)2 / Bi(OTf)3 / (Zn / CF3COOH)-mediated
reaction of arylsulfonyl amides with arylamines.7 In recent years,
research has focused mainly on metal-catalyzed amination
reaction; examples include Ir-catalyzed C-H amination with
anilines,8a Rh, Ru or Fe-catalyzed C-H amination with azides,8b-g
12
2. Results and Discussion
At the outset of our investigation, the reaction between
phenylhydrazine (1a) and aniline (2a) in the presence of
Cu(OAc)2 was selected for optimization. The initial result was
quite promising; diphenylamine (3a) was obtained, although in
only 10% yield (Table 1, entry 1). Meanwhile, no reactions were
observed with CuPc and Mn(OAc)3 (Table 1, entries 2-3). Hence,
we turned to a two-component system such as CoPc/Cu(OAc)2,
FePc/Cu(OAc)2 and Mn(OAc)3/ Cu(OAc)2. To our delight, the
Mn(OAc)3 / Cu(OAc)2 system resulted in 45% yield of 3a (Table
1, entries 4-6); in this case, a stochiometric amount of Mn(OAc)3
was required. Notably, low yield of product was observed due to
unconsumed aniline, thus the manner of addition of
phenylhydrazine was changed. When phenylhydrazine was
introduced successively at a rate of 0.2 mmol per hour, an
improved yield of product was obtained (Table 1, entry 8).
Encouraged by this result, the catalytic system in entry 8 was
Pd-catalyzed amination of aryl sulfides with anilines,9 Pd-
catalyzed reaction of nitroarenes and cyclohexanones.
development of novel, efficient and cost-effective method for
constructing such an important framework is still highly desirable.
On the basis of our previous studies on arylhydrazines and C−N
bond formation 11, arylhydrazines are known to be good radical
10
The

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2
Tetrahedron
replaced with CoPc/Cu(OAc)2
system under the same
conditions. To our surprise, the yield significantly increased from
20% to 60% thus indicating that the batch addition of
phenylhydrazine is beneficial for this reaction (Table 1, entry 9).
After screening the reaction temperature, time and ratio of 1a/2a
(Table 1, entries 9-14), the optimal reaction conditions were
determined to be: phenylhydrazine (2.0 equiv), aniline (1.0
Table 2. Reactions of phenylhydrazine (1a) with substituted
anilines (2)a
o
equiv), 10 mol% of CoPc and Cu(OAc)2) in CH3CN at 0 C for
13 hours (Table 1, entry 12).
Table 1. Optimization of the reaction conditionsa
Entry
Cat.b)
Temp.Time 1a
/oC /h
(equiv)
Yield
/%c)
10
1
2
3
4
5
6
Cu(OAc)2 (1 equiv)
CuPc (1 equiv)
0
0
0
0
0
0
3
3
3
3
3
3
1.5
1.5
1.5
1.5
1.5
1.5
N.D.
trace
20
Mn(OAc)3 (3 equiv)
CoPc/Cu(OAc)2
FePc/Cu(OAc)2
18
Mn(OAc)3(3
45
equiv)/Cu(OAc)2
Mn(OAc)3(3equiv)
/Cu(OAc)2
Mn(OAc)3(3equiv)
/Cu(OAc)2
7
8
9
15
0
3
1.5
1.5
20
12
60d)
CoPc/Cu(OAc)2
0
-5
15
0
12
12
12
13
15
13
1.5
1.5
1.5
2
60d)
22d)
45d)
80d)
79d)
80d)
10 CoPc/Cu(OAc)2
11 CoPc/Cu(OAc)2
12 CoPc/Cu(OAc)2
13 CoPc/Cu(OAc)2
14 CoPc/Cu(OAc)2
0
2
0
2.5
a
Reaction conditions: 2a (1.0 mmol), CH3CN (4 mL) in air for all the
reactions;
b Using 10% mol catalyst for all the reactions, except noted otherwise;
c Isolated yields;
d
Phenylhydrazine was introduced successively at a rate of 0.2 mmol per
hour.
The optimal conditions were applied to a variety of substituted
anilines. Anilines with para-electron-donating groups such as
CH3 and OCH3 produced the expected diarylamines in good
yields (Table 2, entries 2-3); a slight reduction in yield was
observed with para-NH2 substrate since both NH2 group could
participate in the amination reaction (Table 2, entry 10). Anilines
with para-electron-withdrawing groups such as F, Cl, Br,
COOMe, NO2 and CN all reacted smoothly although a slight
drop in yield was observed (58-75%, Table 2, entries 4-9). With
ortho-substituted anilines, results indicated that
a small
substituent such as CH3, NH2 had little effect on the yield. 2-
Methylaniline gave the expected product 3n in 75% yield similar
to yields of products obtained from 3- and 4-methylanilines
(Table 2, entries 2, 11 and 14). On the other hand, 2,6-
diethylaniline and 2-tert-butylaniline gave moderate amounts of
3o and 3p respectively (Table 2, entries 15 and 16). In addition,
lower yield of 3m was obtained from 2-nitroaniline as compared
with product yields obtained from 3- and 4-nitroanilines (Table 2,
entries 8, 12 and 13). These results indicated that bulky groups at
ortho-position of aniline could impede the reaction.
a
Reaction conditions: phenylhydrazine (1a, 2.0 mmol in 2 mL CH3CN)
was introduced successively at a rate of 0.2 mmol per hour, arylamine
(2, 1.0 mmol), 10 mol% of CoPc and Cu(OAc)2 in CH3CN (5 mL) at 0
oC for 13 h in air;
b Isolated yields.

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3
Cu(OAc)2/CoPc instead of CuPc/CoPc as a catalytic system, the
reaction afforded diphenylamine (3a) in 80% yield (Scheme 1,
With the above results in hand, we extended this procedure to
different types of amino compounds. β-Aminonaphathalene (2r)
produced majorly the expected product 3r along with by-product
3r′ which was generated from the reaction of 3r and phenyl
radical (Table 3, entry 1). This indicated that the α-position of 2r
was more reactive. The electron-deficient 2-aminopyridine (2s)
afforded the expected product 3s in a moderate 58% yield (Table
3, entry 2). Reactions involving secondary amines such as N-
methylaniline(2t), diphenylamine (2u) and piperidine (2v) were
also tested; 2t gave the expected product 3t in 60% yield,
however, no desired products were observed with 2u and 2v
(Table 3, entries 3-5). Also, the reaction of phenylhydrazine (1a)
with alkylamines such as benzylamine (2w) and n-hexylamine(2x)
were performed, the expected products 3w and 3x were obtained
in moderate yields (Table 3, entries 6-7). Finally, indole and
benzamide were subjected to the reaction conditions; however no
products were observed (Table 3, entries 8-9). These results
indicated that this protocol is chemoselective. Subsequently, the
effect of substitution on arylhydrazines was probed. As shown in
Table 4, arylhydrazines (1) bearing electron-donating substituents
such as CH3 and OCH3 afforded diarylamines (3) in very good
yields (Table 4, entries 1-3). On the contrary, the presence of
electron-withdrawing groups such as F, Cl, Br, COOCH3 and
NO2 were unfavorable to the reaction; reduced yields ranging
from 25-71% were observed (Table 4, entries 4-9). The effect of
ortho-substituents on the reaction was also probed;
arylhydrazines (1) with ortho-substituents such as CH3
suppressed the reaction (Table 4, entry 10). Finally, the reaction
of an alkylhydrazine, tert-butylhydrazine was carried out but no
expected product was observed (Table 4, entry 11) thus
indicating that alkylhydrazines are not suitable precursors for
alkyl radical under this process.
Table 3 Reactions of phenylhydrazine (1a) with different
types of amino compounds (2)a
For further mechanistic insight, a series of control experiments
have been done. First, the oxidation of phenylhydrazine (1a) with
different oxidants including CoPc, Cu(II)−NH2Ph complex (8)
and air (O2) were carried out, respectively. The results indicated
that phenylhydrazine (1a) could be oxidized by CoPc or
Cu(II)−NH2Ph complex (8) to form phenyldiazine (5a)(Scheme 1,
equations 1 and 2), however, the oxidation efficiency of 8
compared with CoPc is very low (Scheme 1, equations 3 and 4);
the case with air (O2) as oxidant gave a small amount of
complicated mixtures after 12 h, while most of phenylhydrazine
(1a) remained unchanged (Scheme 1, equation 5). On the basis of
results obtained, it can conclude that CoPc played a main role in
the oxidation of phenylhydrazine (1a) to phenyldiazine (5a).
Second, to understand the oxidation process of phenyldiazine
(5a), the reactions of 5a with CoPc, Cu(II)−NH2Ph complex (8)
and air (O2) were carried out, respectively. The results indicated
that 5a is difficult to be oxidized by CoPc and Cu(II)−NH2Ph
complex (8), while air (O2) could oxidize 5a easily to phenyl
radical (7a), which was trapped by TEMPO to afford 10 (Scheme
1, equations 1 and 2). In addition, the result showed that
phenyldiazine (5a) decomposed at 50 oC (Scheme 1, equation 1).
Third, to have an insight into the action of Cu(II)−NH2Ph
complex (8), several control experiments have been done. The
structure of CoPc and CuPc is shown in Scheme 2, cobalt ion
coordinates with 4 nitrogen atoms of ligand phthalocyanine, it is
difficult to coordinate with substrate aniline, so the reaction of
phenylhydrazine (1a) with aniline (2a) gave no expected
diphenylamine (3a) (Scheme 1, equation 6). CuPc is similar to
CoPc, so using CuPc/CoPc as a catalytic system, no expected 3a
was found (Scheme 1, equation 7) because of copper ion in CuPc
has no ability to coordinate with aniline. On the contrast, using
a
Reaction conditions: phenylhydrazine (1a, 2.0 mmol in 2 mL CH3CN)
was introduced successively at a rate of 0.2 mmol per hour, amino
compounds (2, 1.0 mmol), 10 mol% of CoPc and Cu(OAc)2 in
CH3CN (5 mL) at 0 oC for 13 h in air;
b Isolated yields;
C Not detected.
equation 3) because of Cu(OAc)2 is able to coordinate with
aniline to form Cu(II)−NH2Ph complex (8), it can further trap
reactive phenyl radical (7a) to form complex 9 (Scheme 3).

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4
Tetrahedron
Furthermore, Cu(OAc)2-catalyzed reaction was also carried out,
CoPc to form aryldiazenes (5) through successive oxidation
processes via an intermediate arylhydrazyl radical (4).
affording diphenylamine (3a) in only 6% yield (Scheme 1,
Table 4 Reactions of substituted hydrazines (1) with aniline
(2a) a
a Reaction conditions: substituted hydrazine (1, 2.0 mmol in 2 mL CH3CN)
was introduced successively at a rate of 0.2 mmol per hour, aniline (2a, 1.0
mmol), 10 mol% of CoPc and Cu(OAc)2 in CH3CN (5 mL) at 0 oC for 13 h
in air;
b Isolated yields.
c) Not detected.
equation 4) due to low efficiency of Cu(II)−NH2Ph complex (8)
oxidizing phenylhydrazine (1a) to phenyldiazine (5a), so the
combination of CoPc/Cu(OAc)2 is a better choice for N-arylation
of amines with arylhydrazines leading to N-aryl amines.
Scheme 1. The oxidation of phenylhydrazine (1a) with CoPc,
Cu(II)−NH2Ph complex (8) and air (O2)
Scheme 2. The structure of CoPc and CuPc
Aryldiazenes (5) are easily oxidized to the aryldiazenyl radicals
(6) by air (O2), followed by release of N2 to generate aryl radical
(7). Aryl radical (7) can be trapped by complex 8 formed in situ
On the basis of results obtained, a plausible mechanism is
proposed in Scheme 3. The arylhydrazines (1) can be oxidized by

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5
from Cu(OAc)2 and amine (2) to produce complex 9, followed by
4-Methyl-N-phenylaniline (3b). 13
reductive elimination to afford product 3.
o
1
White solid; m.p. 86–89 C, yield 79% (144.8 mg). H NMR
(400 MHz, CDCl3): δ 7.21–7.25 (m, 2H), 7.08 (d, J = 8.2 Hz, 2H),
6.99–7.01 (m, 4H), 6.87 (t, J = 7.3 Hz, 1H), 5.59 (br, s, 1H), 2.30
(s, 3H); 13C NMR (100 MHz, CDCl3): δ 144.0, 140.3, 131.0,
129.9, 129.3, 120.3, 118.9, 116.9, 20.7. MS (ESI-TOF) m/z:
(M+H)+ Calcd for C13H14N 184.1, found 184.1.
4-Methoxy-N-phenylaniline (3c). 13
o
1
White solid; m.p. 99–101 C, yield 80% (159.4 mg). H NMR
(400 MHz, CDCl3): δ 7.21 (t, J = 7.7 Hz, 2H), 7.07 (d, J = 5.7 Hz,
2H), 6.83–6.91 (m, 5H), 5.49 (br, s, 1H), 3.80 (s, 3H); 13C NMR
(100 MHz, CDCl3): δ 155.4, 145.3, 135.8, 129.3, 122.2, 119.6,
115.6, 114.7, 55.6. MS (ESI-TOF) m/z: (M+H)+ Calcd for
C13H14NO 200.1, found 200.1.
Scheme 3. Proposed CoPc/Cu(OAc)2 relay catalysis mechanism
4-Fluoro-N-phenylaniline (3d). 13
Brown solid; m.p. 35–36 oC, yield 70% ( 130.9 mg). H NMR
1
3. Conclusion
(400 MHz, CDCl3): δ 7.22–7.25 (m, 2H), 6.95–7.06 (m, 6H),
6.90 (t, J =7.3 Hz, 1H), 5.59 (br, s, 1H); 13C NMR (100 MHz,
CDCl3): δ 159.3, 156.9, 143.9, 138.9 (d, J = 2.4 Hz), 129.4, 120.6
(d, J = 8.2 Hz), 116.8, 116.0 (d, J = 22.5 Hz). MS (ESI-TOF) m/z:
(M+H)+ Calcd for C12H11FN 188.1, found 188.1.
In summary, we have developed a method for N-aryl amine
synthesis through N-arylation of amines with arylhydrazines by
employing air as a main oxidant, CoPc as a catalytic oxidant, and
Cu(OAc)2 as a catalyst. The best yields were achieved with
arylamines and arylhydrazines, but N-aryl-N-alkylamines and N-
alkylamines could be utilized as well. This protocol provides a
general route to diarylamines, N-aryl-N-alkylamines and N,N-
diary-N-alkyltriamines.
4-Chloro-N-phenylaniline (3e). 13
o
1
Brown solid; m.p. 66–68 C, yield 74% (150.7 mg). H NMR
(400 MHz, CDCl3): δ 7.27–7.29 (m, 2H), 7.18–7.22 (m, 2H),
7.04 (d, J = 7.7 Hz, 2H), 6.93–6.99 (m, 3H), 5.66 (br, s, 1H); 13
C
4. Experimental Section
4.1. General
NMR (100 MHz, CDCl3): δ 142.7, 141.9, 129.5, 129.3, 125.5,
121.5, 118.8, 118.1. MS (ESI-TOF) m/z: (M+H)+ Calcd for
C12H11ClN 204.1, found 204.1.
4-Bromo-N-phenylaniline (3f). 1
1
All reactions were performed in air. H NMR (400 MHz) and
13C NMR (125 or 100 MHz) spectra were determined on a
Varian-Inova 300 MHz or 400 MHz spectrometer with CDCl3 or
DMSO-d6 as solvent and tetramethylsilane (TMS) as internal
standard. Chemical shifts were reported in ppm from internal
TMS (δ), all coupling constants (J values) were reported in Hertz
(Hz). Mass spectra were recorded on a microTOF-Q III (ESI).
Column chromatography was performed with 300-400 mesh
silica gel using flash column techniques. All of the reagents were
used directly as obtained commercially unless otherwise noted.
o
1
Brown solid; m.p. 85–86 C, yield 75% (186.1 mg). H NMR
(400 MHz, CDCl3): δ 7.34 (d, J = 8.7 Hz, 2H), 7.25–7.29 (m, 2H),
7.05 (d, J = 7.7 Hz, 2H), 6.92–6.98 (m, 3H), 5.66 (br, s, 1H); 13
C
NMR (100 MHz, CDCl3): δ 142.5, 142.4, 132.2, 129.5, 121.7,
119.0, 118.3, 112.6. MS (ESI-TOF) m/z: (M+H)+ Calcd for
C12H11BrN 248.0, found 248.0.
Methyl 4-(phenylamino)benzoate (3g). 14
o
1
4.2. General procedure for the preparation of N-aryl amines
3.
Colorless solid; m.p. 115–117 C, yield 69% (156.8 mg). H
NMR (400 MHz, CDCl3): δ 7.89–7.93 (m, 2H), 7.31–7.35 (m,
2H), 7.15–7.18 (m, 2H), 7.04–7.08 (m, 1H), 6.96–7.00 (m, 2H),
6.08 (br, s, 1H), 3.87 (s, 3H); 13C NMR (100 MHz, CDCl3): δ
167.0, 148.1, 140.9, 131.5, 129.5, 123.1, 121.1, 120.4, 114.6,
51.7. MS (ESI-TOF) m/z: (M+H)+ Calcd for C14H14NO2 228.1,
found 228.1.
General procedure for N-arylation of amines(2) with
arylhydrazines(1). Into a 25 mL round-bottom flask, amine (2) (1
mmol), Cu(OAc)2 (0.02 g, 0.1 mmol) and acetonitrile (4 mL)
o
were added, the mixture was stirred and cooled to 0 C. Then,
CoPc (0.057 g, 0.1 mmol) was added, the solution of
arylhydrazine (1) (2 mmol) in acetonitrile (2 mL) was added
successively at a rate of 0.2 mmol per hour while stirring for 13
hours in air. After completion of the reaction (monitored by TLC
analysis (developing solvent: ethyl acetate/petroleum ether (1:8)),
the mixture was filtered, concentrated, and the residue was
further purified by column chromatography using ethyl
acetate/petroleum ether (1:100) as eluent to afford N-aryl amine 3.
4-Nitro-N-phenylaniline (3h). 15
o
1
Yellow solid; m.p. 132–134 C, yield 58% (124.2 mg). H
NMR (400 MHz, CDCl3): δ 8.12 (d, J = 9.1 Hz, 2H), 7.39 (t, J =
7.9 Hz, 2H), 7.15–7.22 (m, 3H), 6.94 (d, J = 9.1 Hz, 2H), 6.27
(br, s, 1H); 13C NMR (100 MHz, CDCl3): δ 150.2, 139.8, 139.5,
129.8, 126.3, 124.7, 122.0, 113.7. MS (ESI-TOF) m/z: (M+H)+
Calcd for C12H11N2O2 215.1, found 215.1.
4.3 Characterization
Diphenylamine (3a). 13
4-(Phenylamino)benzonitrile (3i). 16
o
1
Yellow solid; m.p. 97–98 C, yield 60% (116.5 mg). H NMR
(400 MHz, CDCl3): δ 7.47 (d, J = 8.6 Hz, 2H), 7.36 (t, J = 7.8 Hz,
2H), 7.17 (d, J = 7.8 Hz, 2H), 7.12 (t, J = 7.4 Hz, 1H), 6.97 (d, J
= 8.6 Hz, 2H), 6.09 (br, s, 1H); 13C NMR (100 MHz, CDCl3): δ
148.0, 140.0, 133.8, 129.7, 124.0, 121.3, 119.9, 114.9, 101.5. MS
(ESI-TOF) m/z: (M+H)+ Calcd for C13H11N2 195.1, found 195.1.
o
1
White solid; m.p. 52–54 C, yield 80% (135.4 mg). H NMR
(400 MHz, CDCl3): δ 7.25–7.29 (m, 4H), 7.07–7.09 (m, 4H),
6.93 (t, J = 7.3 Hz, 2H), 5.74 (br, s, 1H); 13C NMR (100 MHz,
CDCl3): δ 143.1, 129.4, 121.0, 117.8. MS (ESI-TOF) m/z:
(M+H)+ Calcd for C12H12N 170.1, found 170.1.

ACCEPTED MANUSCRIPT
6
Tetrahedron
N-Phenyl-1,4-benzenediamine (3j). 17
7.01 (t, J = 7.3 Hz, 1H), 6.72–6.83 (m, 5H), 5.12 (br, s, 1H), 3.64
(br, s, 2H); 13C NMR (100 MHz, CDCl3): δ 145.4, 141.9, 129.3,
128.6, 125.7, 124.9, 119.3, 119.2, 116.2, 115.2. MS (ESI-TOF)
m/z: (M+H)+ Calcd for C12H13N2 185.1, found 185.1.
N1, N2-Diphenylbenzene-1,2-diamine (3q’). 23
o
1
Brown solid; m.p. 69–71 C, yield 72% (132.6 mg). H NMR
(400 MHz, CDCl3): δ 7.18 (dd, J = 8.2, 7.6 Hz, 2H), 6.97 (d, J =
8.4 Hz, 2H), 6.85 (d, J = 7.8 Hz, 2H), 6.79 (t, J = 7.3 Hz, 1H),
6.67 (d, J = 8.4 Hz, 2H), 5.39 (br, s, 1H), 3.18 (br, s, 2H); 13C
NMR (100 MHz, CDCl3): δ 145.9, 142.1, 133.9, 129.3, 12.3,
119.0, 116.2, 115.1. MS (ESI-TOF) m/z: (M+H)+ Calcd for
C12H13N2 185.1, found 185.1.
Brown solid; m.p. 107–108 C, yield 40% (104.1 mg). 1H
o
NMR (400 MHz, CDCl3): δ 7.21–7.29 (m, 6H), 6.91–7.04 (m,
8H), 5.57 (br, s, 2H); 13C NMR (100 MHz, CDCl3): δ 143.9,
134.9, 129.3, 123.0, 120.6, 120.3, 117.3. MS (ESI-TOF) m/z:
(M+H)+ Calcd for C18H17N2 261.1, found 261.1.
3-Methyl-N-phenylaniline (3k). 14
o
1
Yellow solid; m.p. 30–31 C, yield 76%( 139.3 mg). H NMR
(400 MHz, CDCl3): δ 7.23 (t, J = 7.8 Hz, 2H), 7.13 (t, J = 8.1 Hz,
1H), 7.03 (d, J = 8.1 Hz, 2H), 6.86–6.92 (m, 3H), 6.73 (d, J = 7.5
Hz, 1H), 5.59 (br, s, 1H), 2.28 (s, 3H); 13C NMR (100 MHz,
CDCl3): δ 143.3, 143.2, 139.3, 129.4, 129.3, 122.0, 120.9, 118.6,
117.9, 115.0, 21.6. MS (ESI-TOF) m/z: (M+H)+ Calcd for
C13H14N 184.1, found 184.1.
N-Phenylnaphthalen-2-amine (3r). 14
o
1
White solid; m.p. 107–108 C, yield 57% ( 125.0 mg). H
NMR (400 MHz, CDCl3): δ 7.73 (d, J = 8.6 Hz, 2H), 7.64 (d, J =
8.2 Hz, 1H), 7.43 (d, J = 1.8 Hz, 1H), 7.38–7.42 (m, 1H), 7.28–
7.32 (m, 3H), 7.22 (dd, J = 8.8, 2.3 Hz, 1H), 7.15–7.17 (m, 2H),
6.98 (t, J = 7.3 Hz, 1H), 5.82 (br, s, 1H); 13C NMR (100 MHz,
CDCl3): δ 142.7, 140.6, 134.6, 129.5, 129.4, 129.3, 127.7, 126.6,
126.5, 123.7, 121.8, 120.1, 118.5, 112.1. MS (ESI-TOF) m/z:
(M+H)+ Calcd for C16H14N 220.1, found 220.1.
3-Nitro-N-phenylaniline (3l). 15
o
1
Yellow solid; m.p. 86–88 C, yield 56% (120.0 mg). H NMR
(400 MHz, CDCl3): δ 7.84 (t, J = 2.1 Hz, 1H), 7.69 (dd, J = 8.0,
1.2 Hz, 1H), 7.27–7.38 (m, 4H), 7.14 (d, J = 7.6 Hz, 2H), 7.08 (t,
J = 7.4 Hz, 1H), 5.94 (br, s, 1H); 13C NMR (125 MHz, CDCl3): δ
149.3, 145.1, 140.9, 130.0, 129.7, 123.2, 121.8, 119.9, 114.7,
110.3. MS (ESI-TOF) m/z: (M+H)+ Calcd for C12H11N2O2 215.1,
found 215.1.
N,1-Diphenylnaphthalen-2-amine (3r’). 24
1
Brown oil, yield 25% (73.9 mg). H NMR (400 MHz, CDCl3):
δ 7.74–7.78 (m, 2H), 7.58 (d, J = 8.9 Hz, 1H), 7.51 (t, J = 7.4 Hz,
2H), 7.41–7.45 (m, 1H), 7.33–7.38 (m, 3H), 7.27–7.30 (m, 2H),
7.19–7.24 (m, 2H), 7.00 (d, J = 7.7 Hz, 2H), 6.92 (t, J = 7.3 Hz,
1H), 5.53 (br, s, 1H). 13C NMR (100 MHz, CDCl3): δ 143.6,
138.1, 136.7, 133.9, 131.0, 129.39, 129.38, 129.3, 128.4, 128.0,
127.9, 126.4, 125.3, 125.0, 123.4, 121.5, 118.9, 118.7. MS (ESI-
TOF) m/z: (M+H)+ Calcd for C22H18N 296.1, found 296.1.
2-Nitro-N-phenylaniline (3m). 18
o
1
Yellow solid; m.p. 74–75 C, yield 30% (64.3 mg). H NMR
(400 MHz, CDCl3): δ 9.49 (br, s, 1H), 8.20 (dd, J = 8.6, 1.3 Hz,
1H), 7.42 (t, J = 7.8 Hz, 1H), 7.39–7.33 (m, 1H), 7.21–7.29 (m,
4H), 6.75–6.79 (m, 1H); 13C NMR (125 MHz, CDCl3): δ 143.1,
138.7, 135.7, 133.2, 129.7, 126.7, 125.6, 124.4, 117.5, 116.0. MS
(ESI-TOF) m/z: (M+H)+ Calcd for C12H11N2O2 215.1, found
215.1.
N-Phenylpyridin-2-amine (3s). 25
o
1
Colorless solid; m.p. 106–108 C, yield 58% (98.7 mg). H
NMR (400 MHz, CDCl3): δ 8.19–8.20 (m, 1H), 7.45–7.49 (m,
1H), 7.33 (s, 2H), 7.32 (s, 2H), 7.08 (br, s, 1H), 7.02–7.06 (m,
1H), 6.88 (d, J = 8.4 Hz, 1H), 6.70–6.73 (m, 1H); 13C NMR (100
MHz, CDCl3): δ 156.2, 148.3, 140.5, 137.8, 129.3, 122.8, 120.5,
114.9, 108.2. MS (ESI-TOF) m/z: (M+H)+ Calcd for C11H11N2
171.1, found 171.1.
2-Methyl-N-phenylaniline (3n). 19
o
1
Brown solid; m.p. 39–40 C, yield 75% (137.5 mg). H NMR
(400 MHz, CDCl3): δ 7.23 (t, J = 7.8 Hz, 3H), 7.18 (d, J = 7.2 Hz,
1H), 7.12 (t, J = 7.6 Hz, 1H), 6.94 (d, J = 8.0 Hz, 1H), 6.91–6.86
(m, 1H), 5.28 (br, s, 1H), 2.24 (s, 3H); 13C NMR (100 MHz,
CDCl3): δ 144.0, 141.2, 131.0, 129.4, 128.4, 126.8, 122.1, 120.5,
118.9, 117.5, 18.0. MS (ESI-TOF) m/z: (M+H)+ Calcd for
C13H14N 184.1, found 184.1.
N-Methyl-N-phenylaniline (3t). 26
Brown oil, yield 60% (110.0 mg). 1H NMR (400 MHz, CDCl3):
δ 7.25–7.29 (m, 4H), 7.01–7.03 (m, 4H), 6.93–6.97 (m, 2H), 3.32
(s, 3H); 13C NMR (100 MHz, CDCl3): δ 149.0, 129.2, 121.3,
120.5, 40.3. MS (ESI-TOF) m/z: (M+H)+ Calcd for C13H14N
184.1, found 184.1.
2,6-Diethyl-N-phenylaniline (3o). 20
Amber oil, yield 56% (126.2 mg). 1H NMR (400 MHz, CDCl3):
δ 7.11–7.23 (m, 5H), 6.72 (t, J = 7.3 Hz, 1H), 6.48 (d, J = 7.7 Hz,
2H), 5.14 (br, s, 1H), 2.58 (q, J = 7.5 Hz, 4H), 1.14 (t, J = 7.6 Hz,
6H); 13C NMR (125 MHz, CDCl3): δ 147.3, 142.3, 136.9, 129.2,
126.7, 126.5, 117.9, 113.2, 24.7, 14.7. MS (ESI-TOF) m/z:
(M+H)+ Calcd for C16H20N 226.2, found 226.2.
3-Chloro-N-phenylaniline (3v). 18
Brown oil, yield 55% (112.0 mg). 1H NMR (400 MHz, CDCl3):
δ 7.26–7.30 (m, 2H), 7.13 (t, J = 8.0 Hz, 1H), 7.05–7.07 (m, 2H),
6.96–7.01 (m, 2H), 6.83–6.87 (m, 2H), 5.67 (br, s, 1H); 13C NMR
(100 MHz, CDCl3): δ 144.9, 142.0, 135.0, 130.4, 129.5, 122.1,
120.5, 119.0, 116.7, 115.2. MS (ESI-TOF) m/z: (M+H)+ Calcd
for C12H11ClN 204.1, found 204.1.
2-(tert-Butyl)-N-phenylaniline (3p). 21
Yellow oil, yield 58% (130.7 mg). 1H NMR (400 MHz,
CDCl3): δ 7.42 (dd, J = 7.9, 1.4 Hz, 1H), 7.27 (dd, J = 7.9, 1.3 Hz,
1H), 7.14–7.23 (m, 3H), 7.04–7.08 (m, 1H), 6.79–6.82 (m, 3H),
5.39 (br, s, 1H), 1.43 (s, 9H); 13C NMR (100 MHz, CDCl3): δ
146.0, 143.4, 141.2, 129.3, 127.1, 126.9, 126.0, 123.9, 119.2,
116.0, 34.9, 30.6. MS (ESI-TOF) m/z: (M+H)+ Calcd for C16H20N
226.2, found 226.2.
N-Benzylaniline (3w). 27
1
Brown oil, yield 53% (97.1 mg). H NMR (400 MHz, CDCl3):
δ 7.23–7.36 (m, 5H), 7.16 (t, J = 7.8 Hz, 2H), 6.70 (t, J = 7.3 Hz,
1H), 6.61 (d, J = 8.1 Hz, 2H), 4.29 (s, 2H), 3.98 (s, 1H); 13C
NMR (100 MHz, CDCl3): δ 148.2, 139.5, 129.3, 128.7, 127.6,
127.3, 117.6, 112.9, 48.4; MS (ESI-TOF) m/z: (M+H)+ Calcd for
C13H14N 184.1, found 184.1.
N-Phenylbenzene-1,2-diamine (3q). 22
o
1
Brown solid; m.p. 78–80 C, yield 35% (64.5 mg). H NMR
N-Hexylaniline (3x). 27
(400 MHz, CDCl3): δ 7.18–7.23 (m, 2H), 7.11 (d, J = 7.7 Hz, 1H),

ACCEPTED MANUSCRIPT
7
1
Brown oil, yield 45% (79.8 mg). H NMR (400 MHz, CDCl3):
δ 7.17 (t, J = 7.9 Hz, 2H), 6.68 (t, J = 7.3 Hz, 1H), 6.60 (d, J =
7.7 Hz, 2H), 3.58 (br, s, 1H), 3.10 (t, J = 7.1 Hz, 2H), 1.57–1.65
(m, 2H), 1.30–1.43 (m, 6H), 0.90 (t, J = 6.7 Hz, 3H); 13C NMR
(125 MHz, CDCl3): δ 148.5, 129.2, 117.0, 112.7, 44.0, 31.7, 29.6,
26.9, 22.6, 14.1. MS (ESI-TOF) m/z: (M+H)+ Calcd for C12H20N
178.2, found 178.2.
Ge, S.; Green, R. A.; Hartwig, J. F. J. Am. Chem. Soc.
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2,2,6,6-Tetramethyl-1-phenoxypiperidine (10).28
1
Colorless oil. H NMR (400 MHz, CDCl3): δ 7.25–7.12 (m,
4H), 6.89–6.80 (m, 1H), 1.67–1.54 (m, 5H), 1.45–1.39 (m, 1H),
1.24 (s, 6H), 1.02 (s, 6H). 13C NMR (101 MHz, CDCl3): δ 163.1,
128.2, 119.4, 113.4, 59.8, 39.3, 32.1, 20.0, 16.6. MS (ESI-TOF)
m/z: (M+H)+ Calcd for C15H23NOH 234.1, found 234.1.
Supplementary data
1
The copies of the H NMR and 13C NMR spectra for the
products are available.
Acknowledgements
J.-P.Z. specially thank the National Natural Science
Foundation of China (Nos. 20772088, 21172163, 21472133), the
Priority Academic Program Development of Jiangsu Higher
Education Institutions & State and Local Joint Engineering
Laboratory for Novel Functional Polymeric Materials for their
financial support.
6. Aksenov, A. V.; Aksenov, N. A.; Orazova, N. A.;
Aksenov, D. A.; Dmitriev, M. V.; Rubin, M. RSC Adv.
2015, 5, 84849.
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Tetrahedron
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