Ruthenium (II)-Catalyzed Oxidant-Free Coupling/Cyclization of Benzimidates and Sulfoxonium Ylides to Form Substituted Isoquinolines

Article abstract of DOI:10.1002/adsc.201800844

A ruthenium-catalyzed direct mono-C?H functionalization/annulation cascade reaction of benzimidates and sulfoxonium ylides has been developed. The reaction proceeds smoothly with a broad range of substrates, giving access to a variety of isoquinoline deri

Full text of DOI:10.1002/adsc.201800844

Title: Ruthenium(II)-Catalyzed Oxidant-Free Coupling/Cyclization
of Benzimidates and Sulfoxonium Ylides to Form Substituted
Isoquinolines
Authors: Xinxia Shi, Rongchao Wang, Xiaofei Zeng, Yilan Zhang,
Huilin Hu, Chunsong Xie, and Min Wang
This manuscript has been accepted after peer review and appears as an
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To be cited as: Adv. Synth. Catal. 10.1002/adsc.201800844
Link to VoR: http://dx.doi.org/10.1002/adsc.201800844

10.1002/adsc.201800844
Advanced Synthesis & Catalysis
COMMUNICATION
DOI: 10.1002/adsc.201((will be filled in by the editorial staff))
Ruthenium(II)-Catalyzed Oxidant-Free Coupling/Cyclization of
Benzimidates and Sulfoxonium Ylides to Form Substituted
Isoquinolines
Xinxia Shi,a Rongchao Wang,a Xiaofei Zenga, Yilan Zhang,a Huiling Hu,a Chunsong
Xie,a and Min Wanga,*
a
College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, 311121, People’s
Republic of China
E-mail: mwang@hznu.edu.cn
Received: ((will be filled in by the editorial staff))
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201######.((Please
delete if not appropriate))
Abstract:
functionalization/annulation
A
ruthenium-catalyzed direct mono-C–H
cascade reaction of
benzimidates and sulfoxonium ylides has been developed.
The reaction proceeds smoothly with a broad range of
substrates, giving access to a variety of isoquinoline
derivatives in moderate to good yields using an organic
acid additive under oxidant free conditions.
Keywords: Benzimidate; Isoquinoline; Oxidant-free;
Ruthenium catalyst; Sulfoxonium ylide
Isoquinoline is a basic core structure in various
biological active natural products,[1] organic
materials[2] and pharmaceuticals.[3] Traditional
methods for the synthesis of isoquinolines include
the Pictet–Spengler and Bischler–Napieralski
reactions, which require harsh conditions and
activated starting materials.[4] Therefore, flexible
methods for the highly efficient synthesis of
isoquinolines and their derivatives have attracted
much research attention. Among these efforts, the
direct C–H functionalization/cyclization of arenes
remains
transition-metal-catalyzed
activation/annulation of substituted imidates
(Scheme
1a),[5] oximes,[6] amidines,[7]
a
commonly used protocol. The
Scheme 1. Previous design and this work: synthesis of
quinolines and isoquinolines.
C–H
synthesis of carbocycles, N-heterocycles, and
fused heteroarenes using NH-sulfoximines,
ketoximes or aryl imidates through rhodium-
catalyzed annulation.[12] More recently, Aïssa and
coworkers reported an efficient rhodium-
oxadiazoles,[8] and hydrazines[9] is the most
efficient method for the construction of
isoquinoline skeleton. However, in most cases, a
stoichiometric amount of oxidants and expensive
metal additives are required. Therefore, the
development of an efficient and operationally
simple process for preparing isoquinolines
remains challenging and in high demand.
catalyzed
cross-coupling
of
carbonyl
oxosulfonium ylides to form aryl ketones,
followed by treatment with a catalytic amount of
iridium
complex
to
afford
annulated
benz[c]acridines in good yields (Scheme 1b).[12a]
Li and coworkers have reported a rhodium-
catalyzed mono C–H functionalization/annulation
reaction of amidines and sulfoxonium ylides to
prepare substituted isoquinolines in good to
excellent yields (Scheme 1c).[12g] Cheng disclosed
Sulfoxonium ylides,[10] which can produce
metal carbenes through rhodium and iridium
catalysis,[11] are used as carbene-transfer reagents.
Compared with diazo compounds, sulfoxonium
ylides have the advantages of simple handling
and good stability, and have been applied to the
1
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10.1002/adsc.201800844
Advanced Synthesis & Catalysis
a Rh-catalyzed dual functionalization/cyclization
reaction of imidates and sulfoxonium ylides, with
the desired C–H functionalized and dual cyclized
delight, a 1:1.5 ratio mixture of 1a and 2a with 5
mol% [Ru(p-cymene)Cl2]2 as catalyst afforded
desired annulation product 3aa in 35% yield after
fused pyrano[4,3,2-ij]isoquinolines afforded in reacting in EtOH at 100 C for 12 h (Table 1,
good yields (Scheme 1d).[12h] When a 1:1 molar entry 1). When 20 mol% AgSbF6 was added, 3aa
ratio of starting materials was used, a mono-C–H was isolated in a slightly decreased yield (32%).
coupling/cyclization occurred, however, the yield To further improve the yield, various organic
was low. Although notable advances have been
made in such transformations, most of them
involve expensive catalysts, such as Ir and Rh
complexes and additives (silver salts). Owing to
its high catalytic activity and low cost, ruthenium
acids were investigated. Several common organic
acids were tested, including acetic acid (AcOH),
pivalic acid (Piv-OH), 1-adamantaneacetic acid
(Adm-1-COOH), and benzoic acid (PhCOOH)
and its derivatives, with 3,5-Me2PhCOOH
has become another attractive metal catalyst for (mesitylenic acid) giving the best result (entries
C–H bond activation, and has been applied as a 3–7). Next, different solvents were screened, with
catalyst in the synthesis of N-heterocyclic the results indicating that EtOH/2,2,2-
compounds, including isoquinolines.[13,14] To our trifluoroethanol (TFE) mixed solvent was the best
knowledge, no effective protocols for the
choice (entry 11). Other sterically bulky acids
ruthenium-catalyzed
transformation
of gave similar results to that of mesitylenic acid
sulfoxonium ylides have been reported.[15] As a (entries 13–15). A lower yield of 3aa (56%) was
continuation of our interest in unactivated C–H achieved when the reaction was performed at a
bond
functionalization
and
carbenoid
lower temperature of 80 C compared with that at 100
chemistry,[16] we herein report a ruthenium- C (entries 17 and 18). Therefore, the best result
catalyzed
C–H coupling/annulation
of
(74% yield) was achieved using [Ru(p-cymene)Cl2]2
(5 mol%) and mesitylenic acid (50 mol%) in
EtOH/TFE at 100 C.It is also worth mentioning that
only trace amount of bis C-H activation product
could be observed under the standard conditions.[17]
With the optimized conditions in hand, we then
investigated the generality of this mono-C–H
functionalization/annulation process. Initially, a
sulfoxonium ylides and benzimidates for the
synthesis of isoquinoline derivatives using only
an inexpensive organic acid additive under
oxidant-free, base-free, and salt-free conditions.
Initially, benzimidate 1a and sulfoxonium ylide
2a were chosen as model substrates. To our
Table 1. Optimization of the reaction conditions.[a]
Table 2. Substrate scope of sulfoxonium ylides.[a]
Yield
Entry Additive
Solvent
(%)[b]
35
32
54
49
52
51
60
48
48
21
74
62
68
70
69
65
56
74
1
none
AgSbF6
AcOH
Piv-OH
Adm-1-COOH
PhCOOH
3,5-Me2PhCOOH
3,5-Me2PhCOOH
3,5-Me2PhCOOH
3,5-Me2PhCOOH
3,5-Me2PhCOOH
3,5-Me2PhCOOH
N-Ac-Ile-OH
2,4-Me2PhCOOH
3,5-tBu2PhCOOH
AcOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
EtOH
TFE
2[c]
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17[d]
18[e]
HFIP
DCE
EtOH/TFE(1:1)
EtOH/HFIP(1:1)
EtOH/TFE (1:1)
EtOH/TFE (1:1)
EtOH/TFE (1:1)
EtOH/TFE (1:1)
EtOH/TFE (1:1)
EtOH/TFE (1:1)
3,5-Me2PhCOOH
3,5-Me2PhCOOH
[a] Reaction conditions: 1a (0.2 mmol, 1.0 equiv), 2a ( 0.3
mmol), additive (0.5 equiv), and [Ru(p-cymene)Cl2]2 (5
mol%) in solvent (2.0 mL) stirred at 100 C for 12 h.
[b] Isolated yields.
[c] 0.2 equiv of AgSbF6 was used.
[a] Reaction conditions: 1a (0.2 mmol), sulfoxonium ylide 2
(0.3 mmol), [Ru(p-cymene)Cl2]2 (5 mol%), mesitylenic
[d] Performed at 80 C.
[e] Performed at 120 C.
2
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10.1002/adsc.201800844
Advanced Synthesis & Catalysis
acid (0.5 equiv.), TFE/EtOH (2 mL, 1:1 (v/v)) at 100 C
for 12 h; isolated yield.
substituted benzimidate was reacted under the
optimized conditions, mixed products 3aa and 3bj
were obtained in 55% yield. When corresponding
alcohols other than ethanol were used as the solvent,
desired isoquinolines 3bi and 3bj were afforded in
60% and 68% yields, respectively.
[b] Using 1 gram of 1a.
series of substituted sulfoxonium ylides were
subjected to this transformation, with the reaction
proceeded smoothly to yield the corresponding
isoquinolines in moderate to good yields (Table 2).
Firstly, sulfoxonium ylides containing F, Cl, Br, CH3,
or CF3 substituents at the para or meta positions of
the aryl ring were investigated. These reactions
proceeded well, affording yields of 60%–75%. Ylides
substituted with OCH3 or t-Bu groups at the para
position reacted well with 1a, giving corresponding
products 3af and 3ag in 66% and 60% yields,
respectively. However, ylides with Cl, Br, or CH3
ortho-substituents gave the desired isoquinolines in
dramatically decreased yields of around 40%.
Naphthalene and heteroaromatic derivatives derived
from sulfoxonium ylides were well tolerated under
the present conditions, affording 3-aryl isoquinolines
3aq and 3ar in 65% and 45% yields, respectively.
Furthermore, alkyl sulfoxonium ylides bearing t-Bu,
i-Pr, and cyclohexyl groups reacted smoothly with 1a
to give products 3as–3au in good yields. Furthermore,
two unbranched alkyl sulfoxonium ylides were
subjected to the optimal reaction conditions, with the
corresponding products 3av and 3aw obtained in 51%
and 45% yields, respectively. Finally, ylide 1a was
also reacted with two representative sulfoxonium
ylides on a gram-scale under optimal conditions,
affording the corresponding products 3aa and 3aw in
slightly reduced yields of 70% and 42%, respectively.
Next, the substrate scope of benzimidate
Scheme 2. Control experiments
To better understand the mechanism of this
transformation, control experiments were designed
and conducted (Scheme 2). First, when benzimidate
d5-1a was used instead of 1a under the optimized
conditions, desired deuterated product d-3aa was
obtained in 71% yield with 29% hydrogen
incorporation at the C-8 position of the product,
indicating a reversible C–H activation process. [14i, 15]
Next, the reaction of a 1:1 mixture of 1a and d5-1a
produced both 3aa and d-3aa in 45% yield. As a D/H
exchange process on d-3aa was involved in the
catalytic sequence, the exact KIE could not be
determined. However, the ratio of products 3aa and
d-3aa indicated a KIE above 3, which suggested that
cleavage of the aromatic C–H bond was the rate-
determining step.
Based on the experimental results above and
previous reports,[18] a plausible reaction pathway was
proposed, starting from the Ru(p-cymene)(RCO2)X
(X = RCO2 or Cl) species, as shown in Scheme 3.
First, C–H metalation of 1a occurs, producing five-
membered cyclic ruthenacycle intermediate A.
Carbene formation then occurs through the reaction
of A with a sulfoxonium ylide, generating carbene
intermediate B through the elimination of DMSO. [15]
Next, migratory insertion of the carbene into the Ru–
C bond affords six-membered ruthenacycle
derivatives
was
investigated
(Table
3).
Unsurprisingly, a variety of benzimidates bearing
election-withdrawing or electron-donating groups at
the 2- or 4-position of the aryl ring reacted smoothly,
affording expected products 3ba–3bj in good yields,
as shown in Table 3. Notably, when isopropyl-
Table 3. Substrate scope of benzimidates.[a]
[
a]Reaction conditions: benzimidate
1
(0.2 mmol),
sulfoxonium ylide 2a (0.3 mmol), [Ru(p-Cymene)Cl2]2 (5
mol %), mesitylenic acid (0.5 equiv) in TFE/EtOH (1/1, 2
mL) at 100 °C for 12 h, isolated yield.
[b] MeOH was used instead of EtOH.
[c] i-PrOH was used instead of EtOH.
Scheme 3. Proposed mechanism of annulative coupling.
3
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10.1002/adsc.201800844
Advanced Synthesis & Catalysis
intermediate C. [11-12, 16] Protonolysis of C with acid
might then occur, producing acylmethylated
intermediate D, which undergoes successive
addition/dehydrating steps under the acidic conditions
to afford product 3aa. [5, 12g, 12h, 15]
In summary, we have developed an
inexpensive ruthenium-catalyzed mono ortho-C–
H functionalization and annulation reaction of
benzimidates and sulfoxonium ylides. A variety
of substrates were used to access biologically
interesting isoquinolines in good yields. The
reaction was conducted using a readily available
organic acid as additive under oxidant-free, base-
free, and salt-free conditions, which are attractive
features of this new method.
Heravi, N. Nazari, Curr. Org. Chem., 2015, 19,
2358.
[5] a) H. Wang, L. Li, S. Yu, Y. Li, X. Li, Org. Lett.,
2016, 18, 2914; b) X. G. Li, M. Sun, Q. Jin, K. Liu,
P. N. Liu, J. Org. Chem., 2016, 81, 3901; c) J.
Wang, S. Zha, K. Chen, F. Zhang, J. Zhu, Org.
Biomol. Chem., 2016, 14, 4848; d) X. Yang, J. Jie,
H. Li, M. Piao, RSC Advances, 2016, 6, 57371; e) S.
Gong, W. Xi, Z. Ding, H. Sun, J. Org. Chem., 2017
,
82, 7643; f) A. Anukumar, M. Tamizmani, M.
Jeganmohan, J. Org. Chem., 2018, 83, 8567.
[6] a) Z.-W. Zhang, A. Lin, J. Yang, J. Org. Chem.,
2014, 79, 7041; b) Z. Zhu, X. Tang, X. Li, W. Wu,
G. Deng, H. Jiang, J. Org. Chem., 2016, 81, 1401; c)
K. Muralirajan, R. Kuppusamy, S. Prakash, C.-H.
Cheng, Adv. Synth. Catal. 2016, 358, 774.
[7] a) Z. Qi, S. Yu, X. Li, Org. Lett., 2016, 18, 700; b) J.
Li, M. Tang, L. Zang, X. Zhang, Z. Zhang, L.
Ackermann, Org.Lett., 2016, 18, 2742; c) J. Li, Z.
Zhang, M. Tang, X. Zhang, J. Jin, Org. Lett., 2016, 18,
3898; d) P. P. Kaishap, G. Duarah, D. Chetia, S.
Gogoi, Org. Biomol. Chem., 2017, 15, 3491; e) Y. Xu,
G. Zhang, X. Yang, X. Li, Chem. Commun., 2018, 54,
670.
Experimental Section
To a 10-mL reaction tube with a screw-cap and a magnetic
stir-bar under an argon atmosphere were added
benzimidate (0.2 mmol), sulfoxonium ylide (1.5 equiv.),
[Ru(p-cymene)Cl2]2 (5.0 mol%), 3,5-dimethylbenzoic acid
(0.5 equiv.), dry ethanol (1.0 mL), and TFE (1.0 mL). The
reaction mixture was stirred at 100 C until the starting
material disappeared (as monitored by TLC). The solvent
was then evaporated under vacuum and the residue
purified by silica gel column chromatography using
petroleum ether as the eluent to afford the desired product.
[8] a) F.Yang, J. Yu, Y. Liu, J. Zhu, Org. Lett., 2017, 19,
2885; b) X. Yu, K. Chen, F. Yang, S. Zha, J. Zhu,
Org. Lett., 2016, 18, 5412; c) Y. Nishii, A. K. Bachon,
S. Moon, C. Bolm, M. Miura, Chem. Lett., 2017, 46,
1347.
[9] a) S. Zhang, D. Huang, G. Xu, S. Cao, R. Wang,
S. Peng, J. Sun, Org. Biomol. Chem., 2015, 13,
7920; b) J. Wang, S. Zha, K. Chen, J. Zhu, Org.
Chem. Front., 2016, 3, 1281.
[10] J. Vaitla, K. H. Hopmann, A. Bayer, Org. Lett.,
Acknowledgements
2017, 19, 6688.
[11] a) I. K. Mangion, I. K. Nwamba, M. Shevlin, M. A.
Huffman, Org. Lett., 2009, 11, 3566; b) R. M. P.
Dias, A. C. B. Burtoloso, Org. Lett., 2016, 18,
3034; c) A. M. Phelps, V. S. Chan, J. G.
Napolitano, S. W. Krabbe, J. M. Schomaker, S.
Shekhar, J. Org. Chem., 2016, 81, 4158; d) J.
Vaitla, A. Bayer, K. H. Hopmann, Angew. Chem.
Int. Ed., 2017, 56, 4277; e) Y. Xu, X. Zhou, G.
Zheng, X. Li, Org. Lett., 2017, 19, 5256; f) R. D.
C. Gallo, A. Ahmad, G. Metzker, A. C. B.
Burtoloso, Chem. Eur. J., 2017, 23, 16980; g) J.
Zhu,S. Sun, J. Cheng, Tetrahedron Lett., 2018, 59,
2284; h) K. S. Halskov, M. R. Witten, G. L.
Hoang, B. Q. Mercado, J. A. Ellman, Org. Lett.,
2018, 20, 2464; i) G. L. Hoang, J. A. Ellman,
Tetrahedron 2018, 74, 3318; j) C. Zhou, F. Fang,
Y. Cheng, Y. Li, H. Liu, Y. Zhou, Adv. Synth.
Catal., 2018, 360, 2546.
We gratefully acknowledge the Natural Science Foundation of
China (No. 21372056), the PCSIRT (IRT 1231), the Natural
Science Foundation of Zhejiang Province (LY17B020007), and
The Pandeng Plan Foundation for Youth Scholars of College of
Material, Chemistry and Chemical Engineering, Hangzhou
Normal University.
References
[1] a) K. W. Bentley, The Isoquinoline Alkaloids,
Harwood Academic Publishers, Amsterdam, 1998
;
b) D. E. Muscarella, K. A. O’Brian, A. T. Lemley, S.
E. Bloom, Toxicol. Sci., 2003, 74, 66; c) M.
Rahnasto, H. Raunio, A. Poso, C. Wittekindt, R. O.
Juvonen, J. Med. Chem., 2005, 48, 440; d) K. W.
Bentley, Nat. Prod. Rep., 2006, 23, 444; e) K.
Bhadra, G. S. Kumar, Med. Res. Rev., 2011, 31, 821.
[2] A. Tsuboyama, H. Iwawaki, M. Furugori, T.
Mukaide, J. Kamatani, S. Igawa, T. Moriyama, S.
Miura, T. Takiguchi, S. Okada, M. Hoshino, K.
Ueno, J. Am. Chem. Soc., 2003, 125, 12971.
[12] a) M. Barday, C. Janot, N. R. Halcovitch, J. Muir,
C. Aïssa, Angew. Chem. Int. Ed., 2017, 56, 13117;
b) Y. Xu, X. Yang, X. Zhou, L. Kong, X. Li, Org.
Lett., 2017, 19, 4307; c) H. Oh, S. Han, A. K.
Pandey, S. H. Han, N. K. Mishra, S. Kim, R. Chun,
H. S. Kim, J. Park, I. S. Kim, J. Org. Chem., 2018
,
83, 4070; d) Y. Xu, G. Zheng, X. Yang, X. Li,
Chem. Commun., 2018, 54, 670; e) P. Hu, Y.
Zhang, Y. Xu, S. Yang, B. Liu, X. Li, Org. Lett.,
2018, 20, 2160; f) K. S. Halskov, M. R. Witten, G.
L. Hoang, B. Q. Mercado, J. A. Ellman, Org. Lett.,
2018, 20, 2464; g) G. Zheng, M. Tian, Y. Xu, X.
Chen, X. Li, Org. Chem. Front., 2018, 5, 998; h)
X. Wu, H. Xiong, S. Sun, J. Cheng, Org. Lett.,
2018, 20, 1396.
[
3] a) V. W. Pike, C. Halldin, C. Crouzel, L. Barrꢀ, D. J.
Nutt, S. Osman, F. Shan, D. R. Turton, S. L. Waters,
Nuc. Med. Biol., 1993, 20, 503; b) K. L. Rinehart,
Med. Res. Rev., 2000, 20, 1; c) B. A. Weissman, L.
Raveh, Neurochem. 2003, 84, 432.
[4] a) J. J. Li, E. J. Corey, Synthesis, 2005, 18, 3181. b)
E. Awuah, A. Capretta, J. Org. Chem., 2010, 75,
5627; c) M. M. Heravi, S. Khaghaninejad, N. Nazari,
Adv. Heterocycl. Chem., 2014, 112, 83; d) M. M.
[13] Selected Ruthenium-catalyzed reviews: a) P. B.
Arockiam, C. Bruneau, P. H. Dixneuf, Chem. Rev.,
4
This article is protected by copyright. All rights reserved.

10.1002/adsc.201800844
Advanced Synthesis & Catalysis
2012, 112, 5879; b) L. Ackermann, Acc. Chem.
Chen, H. Jiang, W. Zeng, Adv.Synth. Catal. 2018
60, DOI: 10.1002/adsc.201800753.
,
Res. 2014, 47, 281; c) V. S. Thirunavukkarasu, S.
I. Kozhushkov, L. Ackermann, Chem. Commun.,
2014, 50, 29; d) S. D. Sarkar, W. Liu, S. I.
Kozhushkov, L. Ackermann, Adv. Synth. Catal.,
2014, 356, 1461; e) J. A. Leitch, C. G. Frost,
Chem. Soc. Rev., 2017, 46, 7145.
[16] a) S. Kong, L. Zhang, X. Dai, L, Tao, C. Xie, L.
Shi, M. Wang, Adv.Synth. Catal. 2015, 357, 2453;
b)X. Shi, L. Zhang, P. Yang, H. Sun, Y. Zhang, C.
Xie, Z. Ou-yang, M. Wang, Tetrahedron Lett.
2018, 59, 1200.
[14] Selected examples for Ruthenium-catalyzed C–H
functionalization/annulation: a) Z. Zuo, X. Yang, J.
Liu, J. Nan, L. Bai, Y. Wang, X. Luan, J. Org.
Chem., 2015, 80, 3349; b) M. Shankar, K. Ghosh,
K. Mukherjee, R. K. Rit, A. K. Sahoo, Org. Lett.,
2016, 18, 6416; c) A. Bechtoldt, C. Tirler, K.
Raghuvanshi, S. Warratz, C. Kornhaaß, L.
Ackermann, Angew. Chem., Int. Ed., 2016, 55,
264; d) H. Miura, S. Terajima, K. Tsutsui, T.
Shishido, J. Org. Chem., 2017, 82, 1231; e) S.
Sharma, S. Singh, A. Kumari, D. M. Sawant, R. T.
Pardasani, Asian J. Org. Chem., 2017, 6, 728; f) R.
N. P. Tulichala, M. Shankar, K. C. K. Swamy, J.
Org. Chem., 2017, 82, 5068; g) M. K. Manna, S.
K. Bhunia, R. Jana, Chem. Commun., 2017, 53,
6906; h) S. Ruiz, C. Carrera, P. Villuendas, E. P.
Urriolabeitia, Org. Biomol. Chem., 2017, 15, 8904;
i) R. Manikandan, M. Tamizmani, M. Jeganmohan,
Org. Lett., 2017, 19, 6678; j) K. Mukherjee, M.
[17] The ratio of 1a
the product distribution of mono C-H activation
product 3aa and bis C-H activation product 4a
: 2a has an observable influence on
,
thereby indicating a controllable mono or bis C-H
bond activation process by substrates’ ratio in this
reaction. For details please see the supporting
information.
[18] a) Y. Aihara, N. Chatani, Chem. Sci., 2013, 4, 664; b)
D. Zell, S. Warratz, D. Gelman, S. J. Garden, L.
Ackermann, Chem. Eur. J., 2016, 22, 1248; c) B.
ꢁtefane, H. B.; ꢂugelj, U. Groꢃelj, P. Kuzman, J.
Svete, F. Poꢄgan, Eur. J. Org. Chem., 2017, 2017,
1855; d) P. Kuzman, F. Pozgan, A. Meden, J. Svete,
B. Stefane, ChemCatChem., 2017 , 9, 3380; e) M.
Moselage, J. Li, F. Kramm, L. Ackermann, Angew.
Chem., Int. Ed., 2017, 56, 5341; f) R. Gramage-Doria,
S. Achelle, C. Bruneau, F. Robin-le Guen, V. Dorcet,
T. Roisnel, J. Org. Chem., 2018, 83, 1462; g) T.
Jeong, S. H. Lee, R. Chun, S. Han, S. H. Han, Y. U.
Jeon, J. Park, T. Yoshimitsu, N. K. Mishra, I. S. Kim,
J. Org. Chem., 2018, 83, 4641; h) Q. Bu, T. Rogge, V.
Kotek, L. Ackermann, Angew. Chem., Int. Ed., 2018,
57, 765.
Shankar, K. Ghosh, A. K. Sahoo, Org. Lett., 2018
,
20, 1914; k) J. Fan, P.-M. Wang, J.-N. Wang, X.
Zhao, Z.-W. Liu, J.-F. Wei, X.-Y. Shi, Sci. China
Chem., 2018, 61, 153.
[15] In the process of the revision of this manuscript, Ru
(II)-catalyzed cyclization of sulfoxonium ylide was
reported by Zeng, see: H. Xie, J. Lan, J. Gui, F.
5
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10.1002/adsc.201800844
Advanced Synthesis & Catalysis
COMMUNICATION
Ruthenium(II)-Catalyzed Oxidant-Free Coupling/
Cyclization of Benzimidates and Sulfoxonium
Ylides to Form Substituted Isoquinolines
Adv. Synth. Catal. Year, Volume, Page – Page
Xinxia Shi, Rongchao Wang, Xiaofei Zeng, Yilan
Zhang, HuiLing Hu, Chunsong Xie, and Min
Wang*
6
This article is protected by copyright. All rights reserved.