Cobalt-catalyzed electrochemical C–H/N–H functionalization of N-(quinolin-8-yl)benzamide with isocyanides

Article abstract of DOI:10.1016/j.tetlet.2019.06.060

An efficient synthesis of functionalized iminoisoindolinone derivatives has been achieved via a mild electrochemical oxidative C–H/N–H functionalization/intramolecular annulations with isocyanides in undivided cell equipped with a nickel cathode. In the presence of earth abundant cobalt catalyst, versatile iminoisoindolinone derivatives obtained in good yields and in a sustainable manner by using electricity as an oxidant in place of stoichiometric amount of silver and copper salts.

Full text of DOI:10.1016/j.tetlet.2019.06.060

Accepted Manuscript
Cobalt-Catalyzed Electrochemical C-H/N-H Functionalization of N-(quino-
lin-8-yl)benzamide with Isocyanides
Jinkang Chen, Licheng Jin, Jian Zhou, Xinpeng Jiang, Chuanming Yu
PII:
S0040-4039(19)30621-5
https://doi.org/10.1016/j.tetlet.2019.06.060
TETL 50901
DOI:
Reference:
To appear in:
Tetrahedron Letters
Received Date:
Revised Date:
Accepted Date:
1 May 2019
23 June 2019
25 June 2019
Please cite this article as: Chen, J., Jin, L., Zhou, J., Jiang, X., Yu, C., Cobalt-Catalyzed Electrochemical C-H/N-H
Functionalization of N-(quinolin-8-yl)benzamide with Isocyanides, Tetrahedron Letters (2019), doi: https://doi.org/
1
0.1016/j.tetlet.2019.06.060
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers
we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and
review of the resulting proof before it is published in its final form. Please note that during the production process
errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Tetrahedron Letters
Cobalt-Catalyzed Electrochemical C-H/N-H Functionalization of
N-(quinolin-8-yl)benzamide with Isocyanides
a
b
b
b*
a,b*
Jinkang Chen , Licheng Jin , Jian Zhou , Xinpeng Jiang and Chuanming Yu
a
Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou 310014, P. R. of
China.
b
College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou 310014, P. R. of China. Email: ycm@zjut.edu.cn; Fax:
+86)571-88320867.
(
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
An efficient synthesis of functionalized iminoisoindolinone derivatives has been achieved via a
mild electrochemical oxidative C-H/N-H functionalization/intramolecular annulations with
isocyanides in undivided cell equipped with a nickel cathode. In the presence of earth abundant
cobalt catalyst, versatile iminoisoindolinone derivatives obtained in good yields and in a
sustainable manner by using electricity as an oxidant in place of stoichiometric amount of silver
and copper salts.
Available online
Keywords:
2
019 Elsevier Ltd. All rights reserved.
Electrochemistry
C-H functionalization
Cobalt
Isocyanide
Oxidant-free
Introduction
material sciences and pharmaceutical industry [1]. Compared
with conventional carbon monoxide, non-gaseous isocyanides
can serve as safer C1 building block in transition metal
catalyzed C-H functionalization and carbonylation, affording
various nitrogen-containing molecules without introducing
highly toxic carbon monoxide [2]. Many isocyanides involved
C-H functionalization were successfully developed by using
noble transition metals, such as palladium [3], rhodium [4],
ruthenium [5], and others [6]. Moreover, earth abundant
metals, including copper [7], cobalt [8], and nickel [9] were
also successfully applied to catalyze isocyanides involved C-H
functionalization. However, it’s worth to note that above
mentioned methodologies require stoichiometric amount of
silver salts, copper salts or even peroxides in redox-processes,
which may either generate undesirable by-products or increase
the risk of explosion [10]. Therefore, the synergistic merger of
electrosynthesis and transition metal-catalysis has made
significant progress to avoid the usage of extra oxidants in C-H
functionalization reactions [11]. In 2007, Jutand group
developed a Pd-catalyzed electrochemical dehydrogenative
heck reaction, in which Pd(0) was continuously oxidized to
Pd(II) species by catalytic amount of benzoquinone generated
from electrochemical oxidation [12]. Subsequently, Kakiuchi
and coworkers described Pd-catalyzed aromatic C-H
halogenations via electrochemistry [13]. Mei group reported
Pd-catalyzed C-H activation/C-C cross-coupling reactions and
C(sp3)-H oxygenation via anodic oxidation [14]. More
recently, Lei and coworkers developed cobalt-catalyzed
electrooxidative C−H amination and C-H/N-H annulation by
Over past decades, transition metal catalyzed C-H
functionalization has been intensively studied and become one
of the most important synthetic strategy broadly applied in
Scheme 1 Recent methods for transition-metal catalyzed
C-H/N-H annulation.

using N-(quinolin-8-yl) benzamide as directing group in
divided cell [15] (Scheme 1b). Ackermann group reported
electrochemistry enabled C-H functionalization and annulation
with N,O-bidentate and 2-(1-methylhydrazinyl) pyridine [16]
as directing groups. In spite of major progress in this field,
divided cells were typically used to avoid the influence of
reduction reaction in cathode and oxidation reaction in anode,
however, the cost-intensive ion exchange membrane employed
in divided cell is inconvenient to operate [17]. Based on our
recently research on C-H functionalization [18], herein, we
report a cobalt-catalyzed electrochemical oxidative C-H/N-H
functionalization and annulations of N-(quinolin-8-yl)
benzamides with isocyanides to synthesize iminoisoindolinone
derivatives [19]. Salient features of this method comprise (1)
oxidative C−H/ N−H functionalization by using electricity as
oxidant in place of stoichiometric amount of silver or copper
salts; (2) less toxic and earth-abundant cobalt catalyst; (3)
cheap cathode (Ni Vs Pt) and mild reaction conditions (50 °C
Vs 100-170 °C); and (4) the reaction was conducted in an
undivided cell.
Table 2
a
Scope of the N-(quinolin-8-yl)benzamides .
Results and Discussion
Initially, N-(quinolin-8-yl)benzamide 1a and tert-butyl
isocyanide 2a were used as model substrates to optimize the
reaction conditions. When 1a and 2a were treated with
Co(acac)
2
, NaOPiv, and n-Bu
4 6
PF in TFE:MeCN = 1:1 at 50
°
C for 16 h under constant current (4 mA), the desired product
3
a was obtained in 42% yield (Table1, entry 1). From a series
of representative solvents (Table 1, and Table S1 in supporting
information), DMF was found to provide the most optimal
result (entry 4). When Co(OAc)
2
was used instead of
Co(acac)
2
, the yield was improved to 55% (entry 6).
Table 1
a
Optimization of the reaction conditions .
a
Reaction conditions: undivided cell, RVC anode, nickel cathode, constant
current at 1.5 mA, N-(quinolin-8-yl)benzamide 1 (0.3 mmol), 2a (0.6
mmol), NaOPiv (0.6 mmol), Zn(OPiv)
50°C, 24 hours. Isolated yield.
b
2
(0.3 mmol), DMF (8 mL), air,
b
Entry
1
Co
additive
NaOPiv
solvent
CCE
yield
(%)
Scale-up reactions: undivided cell, RVC anode, nickel cathode, constant
current at 1.5 mA, 1 (1 mmol), 2a (2 mmol), NaOPiv (2 mmol), Zn(OPiv)
1 mmol), DMF (8 mL), air, 50°C, 48 hours. Isolated yield.
(mA)
2
(
Co(acac)
2
TFE :
4
42
MeCN=1:1
Further screening of additives revealed that NaOPiv was still
the ideal additive (entries 7-9). It is worth noting that during
continuous electrolysis, the cobalt catalyst will continue to
decrease from cathodic electrodeposition [20]. Introduction of
Zn(II) as an additive likely facilitates C−H activation [21] and
acts as an electrolyte in an electrochemical reaction at the same
2
3
4
5
6
7
8
9
Co(acac)
Co(acac)
2
NaOPiv
NaOPiv
TFE
MeCN
4
4
-
43
2
Co(acac)
2
NaOPiv
DMF
4
49
CoCl
2
NaOPiv
NaOPiv
NaOAc
CsOPiv
Zn(OPiv)
NaOPiv
NaOPiv
DMF
DMF
DMF
DMF
DMF
DMF
DMF
4
4
48
55
51
35
-
Co(OAc)
Co(OAc)
Co(OAc)
Co(OAc)
Co(OAc)
Co(OAc)
2
2
2
2
2
2
time. Decreasing the current to 2 mA and using Zn(OPiv)
electrolyte, increased the yield of 3a from 55% to 81% (entry
0). It indicated that reducing current and using Zn(II) might
2
as
4
4
1
2
4
reduce the negative effects of electrodeposition on the cathode.
It was remarkable that the yield rose to 89% while the current
further decreased to 1.5 mA (entry 11). Further reduction in
current might affect the oxidation of the catalyst at the anode,
thus decreased the yield to 68% (Table S1 in supporting
information).
With the optimized reaction conditions in hand, we
explored the scope of N-(quinolin-8-yl)benzamides 1 as
illustrated in Table 2. It was observed that substrates bearing
electron-donating (Me/Ph) and electron-withdrawing group (F)
at the ortho-position of the aromatic ring displayed good
reactivity, giving the desired products 3a-3d in 78–89% yields.
c
1
0
2
81
c,d
1
1
1.5
89
a
Reaction conditions: undivided cell, RVC anode, nickel cathode, constant
current at 4 mA, 1a (0.3 mmol), 2a (0.6 mmol), [Co] (20 mol %), additive
0.6 mmol), n-Bu NPF (0.3 mmol), solvent (8 mL), air, 50 °C, 16 hours.
(
4
6
b
Isolated yield.
Zn(OPiv)
2
c
2
instead of n-Bu
4 hours. RVC = reticulated vitreous carbon. Co(acac)
acetylacetonate. NaOPiv = sodium pivalate. Zn(OPiv) = zinc pivalate.
4
NBF
4
.
d
2
= cobalt(II)
2
TFE = 2,2,2-trifluoroethanol. DMF = N,N-dimethylformamide. CCE =
constant current electrolysis.

Table 3
To demonstrate the synthetic utility of this protocol, scale-up
reactions of 1a and 1b were conducted, and gave
corresponding products 3a and 3b in 90% and 81% yield
respectively. Substrates possessing halides (Cl/Br) and
electron-donating groups (Me/Ph/OMe) at para-position of the
amides’ benzene ring gave corresponding products 3e and 3i-j
in 78-83% yields. However, fluoro, trifluoromethyl, and
a
Substrate scope of sulfoxonium ylides .
methoxy-carbonyl
substituted
amides
furnish
the
corresponding iminoisoindolinones in 47-56% yields, which is
presumably due to the strong electron-withdrawing effect (3f,
3
k, and 3l). Substrates with substituent at meta-position of
benzene ring also showed moderate reactivity, giving 3m-3o in
3-79% yields. Multiple substituted substrate 1p was
compatible with the reaction, delivering the ideal product 3p in
6
8
2
8% yield. Moreover, replacement of benzene ring with
-naphthalene, led to 3q and 3q' in 93% yield (3q/3q' = 1/3.4).
On the other hand, N-(quinolin-8-yl)-1-naphthamide afforded
r in 91%. In sharp contrast, thiophene 1s was an ineffective
3
substrate in this transformation, giving only trace amount of
product. To our delight, acrylamide underwent this reaction
smoothly to form 3t in 77% yield.
Next, the scope of isocyanides 2 was also examined
(
Table 3). The use of 1a and 2-isocyano-1,3-dimethylbenzene
led to the desired product 3aa in 89% yield. The 2-isocyano-
1,3,5-trimethyl benzene and 2-isocyano-1,3-diethyl benzene
were also compatible with the standard reaction conditions,
and gave corresponding products 3ab and 3ac in 88% and 81%
yields respectively. Then the reactions of other isocyanides
were investigated. Phenyl isocyanide afforded 3ae in 39%
yield (E:Z = 4.8:1), but 4-isocyano-1-chlorobenzene failed to
afford desired product 3af. To our delight, 1-adamantyl
isocyanide could furnish the desired product 3ad in 85% yield.
To further understand the reaction mechanism, a series of
control experiments were carried out under optimized
conditions (Scheme 2). Power on/off experiments indicated
that electricity played an important role and exposure to air did
not affect the circulation of the catalyst [22]. Additionally, the
kinetic isotope effect (KIE) value of intermolecular
a
Reaction conditions: undivided cell, RVC anode, nickel cathode, constant
current at 1.5 mA, 1a (0.3 mmol), 2 (0.6 mmol), NaOPiv (0.6 mmol),
Zn(OPiv) (0.3 mmol), DMF (8 mL), air, 50°C, 24 hours. Isolated yield.
2
H D H D
competition (k /k = 1.6) and parallel reactions (k /k = 1.8)
indicated that C–H activation was unlikely involved in the
rate-determining step [23]. Based on the experiments described
above and related literature reports [24],
a plausible
mechanism was proposed in scheme 3. N-(quinolin-8-yl)
benzamide 1a was first coordinated with Co(II) complex to
give intermediate I. Then the cyclometallation was carried out
upon electrooxidative of Co(II) to form intermediate II. Next,
insertion of isocyanide 2a to the Co-C bond of intermediate II
afforded intermediate III. The ideal product 3a and Co(I) were
produced by reductive elimination. At last, Co(II) species was
regenerated via electrooxidative of Co(I) and entered into the
next catalytic cycle [25].
In summary, we have developed a robust strategy for
electrochemical cobalt(II)-catalyzed C-H/N-H annulation of
N-(quinolin-8-yl)benzamide with isocyanides in undivided cell.
Environmental friendly electricity rather than a toxic and
costly transition metal oxidant was used for the oxidation of
Co(I) and Co(II) specIn summary, we have developed a robust
strategy for electrochemical cobalt(II)-catalyzed C-H/N-H
annulation of N-(quinolin-8-yl)benzamide with isocyanides in
undivided cell. Environmental friendly electricity rather than a
toxic and costly transition metal oxidant was used for the
oxidation of Co(I) and Co(II) species. By using appropriate
directing groups and economical nickel cathode, the
transformation could be finished under mild conditions.
Further efforts to apply this method to synthesize bioactive
compounds are currently underway in our laboratory.
Scheme 2 Control experiments.

Supplementary data
Supplementary data associated with this article can be
found, in the online version, at https://
References
[
(
(
(
1] For selected reviews, see: (a) F. Pan and Z.-J. Shi, ACS Catal., 4
2014), 280-288.
b) G. Song and X. Li, Acc. Chem. Res., 48 (2015), 1007-1020.
c) Z. Chen, B. Wang, J. Zhang, W. Yu, Z. Liu and Y. Zhang, Org. Chem.
Front., 2 (2015), 1107-1295.
(d) T. Iwai and M. Sawamura, ACS Catal., 5 (2015), 5031-5040.
(e) B. Liu, F. Hu and B.-F. Shi, ACS Catal., 5 (2015), 1863-1881.
(f) C. Sambiagio, D. Schönbauer, R. Blieck, T. Dao-Huy, G. Pototschnig,
P. Schaaf, T. Wiesinger, M. F. Zia, J. Wencel-Delord, T. Besset, B. U. W.
Maes and M. Schnürch, Chem. Soc. Rev., 47 (2018), 6603-6743.
[
(
[
2] (a) B. Song and B. Xu, Chem. Soc. Rev., 46 (2017), 1103-1123.
b) E, Sheikhhosseini. J. Saudi Chem. Soc., 22 (2018), 337.
3] For selected examples, see: (a) G. Balme, E. Bossharth and N.
Monteiro, Eur. J. Org. Chem., 21 (2003), 4101-4111.
b) M. Tobisu, S. Imoto, S. Ito and N. Chatani, J. Org. Chem., 75 (2010),
835-4840.
(
4
Scheme 3 Proposed reaction mechanism
(
(
(
c) Z. Hu, D. Liang, J. Zhao, J. Huang and Q. Zhu, Chem. Commun., 48
2012), 7371-7373.
d) Y.-J. Liu, H. Xu, W.-J. Kong, M. Shang, H.-X. Dai and J.-Q. Yu,
Experimental section
General information
Nature, 515 (2014), 389-393.
4] (a) C. Zhu, W. Xie and J. R. Falck, Chem. Eur. J., 17 (2011),
2591-12595.
[
1
Unless otherwise noted, all reactions were carried out without
exclusion of air or moisture. Commercial solvents and reagents
were used without further purification. Analytical thin layer
chromatography (TLC) was performed using silica gel GF254
plates. Column chromatography was performed using silica gel
(
(
b) J. Peng, L. Liu, Z. Hu, J. Huang and Q. Zhu, Chem. Commun., 48
2012), 3772-3774.
[5] W. D. Jones and W. P. Kosar, J. Am. Chem. Soc., 108 (1986),
640-5641.
6] (a) S. Marcaccini and T. Torroba, Organic preparations and procedures
international, 25 (1993), 141-208
5
[
(300-400 mesh) eluting with petroleum ether and ethyl acetate.
(
(
b) Z. He, M. Bae, J. Wu and T. F. Jamison, Angew. Chem. Int. Ed., 53
2014), 14451-14455.
1
13
Nuclear magnetic resonance spectra ( H NMR and C NMR)
were recorded with a Bruker Magnet system 400' 54 Ascend
[7] K. Takamatsu, K. Hirano and M. Miura, Org. Lett., 17 (2015),
4066-4069.
1
13
(
H at 400 MHz, C at 100 MHz). Unless otherwise noted, all
spectra were acquired in CDCl . Chemical shifts are reported
in parts per million (ppm, δ), downfield from tetramethylsilane
[
(
(
(
8] (a) D. Kalsi, N. Barsu, P. Dahiya and B. Sundararaju, Synthesis, 49
2017), 3937-3944.
b) T. Jiang, Z.-Y. Gu, L. Yin, S.-Y. Wang and S.-J. Ji, J. Org. Chem., 82
2017), 7913-7919.
3
(
(
TMS, δ=0.00 ppm) and are referenced to residual solvent
1
13
CDCl
3
, δ=7.26 ppm ( H) and 77.0 ppm ( C)). Coupling
(c) F. Zou, X. Chen and W. Hao, Tetrahedron, 73 (2017), 758-763.
constants were reported in hertz (Hz).
(d) D. Kalsi, N. Barsu and B. Sundararaju, Chem. Eur. J., 24 (2018),
2
360-2364.
e) H. Zhao, X. Shao, Z. Qing, T. Wang, X. Chen, H. Yang and H. Zhai,
Adv. Synth. Catal., 2019, DOI: 10.1002/adsc.201801459.
9] W. Hao, J. Tian, W. Li, R. Shi, Z. Huang and A. Lei, Chem. Asian J.,
1 (2016), 1664-1667.
[10] (a) J. Peng, J. Zhao, Z. Hu, D. Liang, J. Huang and Q. Zhu, Org. Lett.,
4 (2012), 4966-4969.
b) S. Xu, X. Huang, X. Hong and B. Xu, Org. Lett., 14 (2012),
614-4617.5294-5297.
11] (a) R. Francke and R. D. Little, Chem. Soc. Rev., 43 (2014),
492-2521.
(
General procedures for the Electrolysis
[
1
An oven dry three necked round-bottomed flask (10 mL) was
charged with the N-(quinolin-8-yl)benzamide (0.3 mmol),
Co(OAc) (20 mol %), NaOPiv (0.6 mmol), Zn(Opiv) (0.3
2 2
mmol) and 8 mL of DMF. The flask was equipped with a
reticulated vitreous carbon (RVC, 100 PPI) anode (1.0 cm x
1
(
4
[
1
.0 cm x 0.5cm) and a nickelrod (99.9 %) cathode (Φ 5 mm).
2
The reaction mixture stirred at room temperature for 5 min,
followed by adding isocyanides (0.6 mmol). The constant
current (1.5 mA) electrolysis was carried out at 50 °C. After
complete consumption of the starting material, the reaction
mixture was cooled to room temperature. The RVC anode and
(b) E. J. Horn, B. R. Rosen and P. S. Baran, ACS Cent. Sci., 2 (2016),
302-308.
[
(
[
12] C. Amatore, C. Cammoun and A. Jutand, Adv. Synth. Catal., 349
2007), 292-296.
13] F. Kakiuchi, T. Kochi, H. Mutsutani, N. Kobayashi, S. Urano, M.
Sato, S. Nishiyama and T. Tanabe, J. Am. Chem. Soc., 131 (2009),
11310-11311.
2 2
nickel rod cathode were washed with CH Cl (10 mL×3) in an
ultrasonic bath. After evaporation of the solvent under vacuum,
the residue was purified by flash column chromatography over
silica gel eluting with petroleum ether/ethyl acetate to give the
desired product. H NMR and C NMR spectrum of products
could be found in supplementary information.
[14] For selected examples, see: (a) C. Ma, C.-Q. Zhao, Y.-Q. Li, L.-P.
Zhang, X.-T. Xu, K. Zhang and T.-S. Mei, Chem. Commun., 53 (2017),
1
(
2189-12192.
b) Q.-L. Yang, Y.-Q. Li, C. Ma, P. Fang, X.-J. Zhang and T.-S. Mei, J.
Am. Chem. Soc., 139 (2017), 3293-3298.
c) Q.-L. Yang, P. Fang and T.-S. Mei, Chinese. J. Org. Chem., 36 (2018),
38-352.
15] For selected examples, see: (a) X. Gao, P. Wang, L. Zeng, S. Tang
1
13
(
3
[
Acknowledgements
and A. Lei, J. Am. Chem. Soc., 140 (2018), 4195-4199.
This work was supported by the National Natural Science
Foundation of China (NSFC) (Grant No. 21676252 and
(b) S. Tang, D. Wang, Y. Liu, L. Zeng and A. Lei, Nat. Commun., 9
(2018), 798.
(c) L. Zeng, H. Li, S. Tang, X. Gao, Y. Deng, G. Zhang, C.-W. Pao, J.-L.
2
1506191).
Chen, J.-F. Lee and A. Lei, ACS Catal., 8 (2018), 5448-5453.
16] For selected examples, see: (a) N. Sauermann, T. H. Meyer, C. Tian
and L. Ackermann, J. Am. Chem. Soc., 139 (2017), 18452-18455.
[

(
b) C. Tian, L. Massignan, T. H. Meyer and L. Ackermann, Angew.
[20] P. Gomes, C. Gosmini and J. Pe´richon, J. Org. Chem. 68 (2003),
1142−1145.
Chem., 130 (2018), 2407-2411.
(
(
(
(
(
c) N. Sauermann, T. H. Meyer, Y. Qiu and L. Ackermann, ACS Catal., 8
2018), 7086-7103.
d) N. Sauermann, R. Mei and L. Ackermann, Angew. Chem. Int. Ed., 57
2018), 5090-5094.
e) R. Mei, N. Sauermann, J. C. A. Oliveira and L. Ackermann, J. Am.
[21] (a) Q. Wang, F. Xie and X. Li. J. Org. Chem. 80 (2015), 8361−8366.
(b) J. Xia, Z. Huang, X. Zhou, X. Yang, F. Wang and X. Li, Org. Lett. 20
(2018), 740−743.
[22] D. Sun and R. Zhang, Org. Chem. Front., 5 (2018), 92-97.
[23] E. M. Simmons and J. F. Hartwig, Angew. Chem. Int. Ed. 51 (2012),
3066−3072.
Chem. Soc., 140 (2018), 7913-7921.
[
[
17] C. Ma, P. Fang and T.-S. Mei, ACS Catal., 8 (2018), 7179-7189.
18] (a) X. Jiang, J. Chen, W. Zhu, K. Cheng, Y. Liu, W.-K. Su and C. Yu,
[24] (a) D. Kalsi, S. Dutta, N. Barsu, M. Rueping and B. Sundararaju,
ACS Catal., 8 (2018), 8115-8120.
J. Org. Chem., 82 (2017), 10665-10672.
b) L. Zhang, X. Zheng, J. Chen, K. Cheng, L. Jin, X. Jiang and C. Yu,
Org. Chem. Front., 5 (2018), 2969-2973.
c) L. Zhang, J. Chen, J. Chen, L. Jin, X. Zheng, X. Jiang and C. Yu,
Tetrahedron Lett., 60 (2019), 1053-1056.
19] During our preparation of this manuscript, a cobaltaelectro-catalyzed
C–H activation with isocyanides was reported by Ackermann group. With
a different directing group, the reaction required harsh conditions (120 °C
for 24 h with a platinum cathode, CCE = 4mA). Sau, S. C., Mei, R.,
Struwe, J. and Ackermann, L., ChemSusChem, 2019, doi:
(b) N. Lv, Z. Chen, Y. Liu, Z. Liu and Y. Zhang, Org. Lett., 20 (2018),
5845-5848
(c) T. H. Meyer, J. C. A. Oliveira, S. C. Sau, N. W. J. Ang and L.
Ackermann, ACS Catal., 8 (2018), 9140-9147.
[25] (a) D. Kalsi and B. Sundararaju, Org. Lett., 17 (2015), 6118-6121
(b) O. Planas, C. J. Whiteoak, A. Company and X. Ribas, Adv. Synth.
Catal., 357 (2015), 4003-4012.
(
(
[
Graphical Abstract
1
0.1002/cssc.201900378.
Cobalt-Catalyzed Electrochemical C-H/N-H
Leave this area blank for abstract info.
Functionalization of N-(quinolin-8-yl)
benzamide with Isocyanides
Jinkang Chen , Licheng Jin , Jian Zhou , Xinpeng Jiang and Chuanming Yu
a
b
b
b*
a,b*
An efficient synthesis of functionalized iminoisoindolinone derivatives has been achieved via a mild electrochemical oxidative C-H/N-H
functionalization/intramolecular annulations with isocyanides in undivided cell equipped with a nickel cathode.




Oxidative C−H/ N−H functionalization
by using electricity as oxidant
Less toxic and earth-abundant cobalt
catalyst
Cheap cathode (Ni) and mild reaction
conditions (50 °C Vs 100-170 °C)
The reaction was conducted in an
undivided cell.