Directing-Group-Assisted C(sp2)-H Arylsulfonylation from Sulfur Dioxide

Article abstract of DOI:10.1021/acs.orglett.0c02400

A straightforward and stereoselective preparation of (Z)-β-alkenyl sulfones through a reaction of N-tosyl acrylamides, 1,4-diazabicyclo[2.2.2]octane-sulfur dioxide, and aryldiazonium tetrafluoroborates under copper catalysis is accomplished. The direct C(sp2)-H arylsulfonylation of acrylamides using sulfur dioxide as the sulfonyl source in the presence of copper trifluoroacetate proceeds smoothly, giving rise to (Z)-β-alkenyl sulfones in good yields. During the reaction process, excellent regio- A nd stereoselectivities are observed.

Full text of DOI:10.1021/acs.orglett.0c02400

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Letter
2
Directing-Group-Assisted C(sp )−H Arylsulfonylation from Sulfur
Dioxide
Tonghao Zhu and Jie Wu*
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ABSTRACT: A straightforward and stereoselective preparation of
Z)-β-alkenyl sulfones through a reaction of N-tosyl acrylamides,
,4-diazabicyclo[2.2.2]octane-sulfur dioxide, and aryldiazonium
(
1
tetrafluoroborates under copper catalysis is accomplished. The
direct C(sp )−H arylsulfonylation of acrylamides using sulfur
2
dioxide as the sulfonyl source in the presence of copper
trifluoroacetate proceeds smoothly, giving rise to (Z)-β-alkenyl
sulfones in good yields. During the reaction process, excellent
regio- and stereoselectivities are observed.
ecause of its excellent atom economy and step economy,
Scheme 1. Synthesis of Alkenyl Sulfones by Using Sulfur
Dioxide as the Sulfonyl Source
B
direct C−H functionalization is an efficient strategy for
the generation of carbon−carbon or carbon−heteroatom
1
2
bonds. Among these transformation, the C(sp )−H sulfony-
lation of alkenes is an important approach for the formation of
alkenyl sulfones, benefiting from the importance of alkenyl
2
sulfones in pharmaceuticals and natural products. Up to now,
continuous methods have appeared and been developed in this
3
field. However, in some cases, the approaches for the direct
2
C(sp )−H sulfonylation of olefins still have some limitations in
terms of the employment of expensive catalysts and the
stoichiometric amount of oxidants or additives. Thus the
development of efficient, green, and straightforward methods
for the preparation of alkenyl sulfones is highly desirable.
Recently, utilizing 1,4-diazabicyclo[2.2.2]octane-sulfur diox-
ide (DABCO·(SO ) ) or potassium/sodium metabisulfite as
acrylamides would be the choice of substrate for the method
development, which would utilize the weakly coordinating
tosyl-imide as the directing group. Herein we report a
straightforward and stereoselective preparation of (Z)-β-
alkenyl sulfones through a reaction of N-tosyl acrylamides,
2
2
7,8
the sulfur dioxide surrogates for the construction of sulfonyl
4
derivatives has attracted much attention. In particular, with
this strategy, efforts have been made for the preparation of
1
,4-diazabicyclo[2.2.2]octane-sulfur dioxide, and aryldiazo-
2
alkenyl sulfones via C(sp )−H sulfonylation. For instance, the
nium tetrafluoroborates under copper catalysis. A radical
process involving arylsulfonyl radicals is proposed. With the
assistance of tosyl-imide as the directing group, (Z)-β-alkenyl
sulfones are stereoselectively formed (Scheme 1, eq b).
The studies were initiated from a reaction of N-tosyl
2
C(sp )−H sulfonylation of alkenes was accomplished via a
reaction of aryldiazonium tetrafluoroborates, sulfur dioxide,
and alkenes using copper salt as a catalyst or via a iodide-
5
a,b
promoted radical-type insertion of sulfur dioxide.
Recently,
2
an iron-chloride-mediated C(sp )−H methylsulfonylation of
alkenes from sulfur dioxide was achieved. Loh and coworkers
described the C(sp )−H sulfonylation of electron-rich olefins
enamides) with sulfur dioxide in the presence of copper(II)
acrylamide 1a, DABCO·(SO ) , and 4-methylphenyldiazonium
5c
2 2
tetrafluoroborate 2a in DCE at 80 °C by using copper
trifluoroacetate as the catalyst. Fortunately, the desired (Z)-2-
2
(
5d,e
triflate or photocatalysis.
Despite these achievements, the
Received: July 19, 2020
thermodynamically stable (E)-alkenyl sulfones are obtained as
the major products (Scheme 1, eq a). So far, there are no
examples of the stereoselective preparation of (Z)-alkenyl
sulfones using sulfur dioxide as the sulfonyl source. Inspired by
2
the recent advances in C(sp )−H bond functionalization
6
assisted by directing groups, we envisioned that N-tosyl
©
XXXX American Chemical Society
https://dx.doi.org/10.1021/acs.orglett.0c02400
A
Org. Lett. XXXX, XXX, XXX−XXX

Organic Letters
pubs.acs.org/OrgLett
Letter
phenyl-N,3-ditosylacrylamide 3aa was observed in 45% yield
Scheme 2. Reaction of N-Tosyl Acrylamide 1a, DABCO·
,
a b
(Table 1, entry 1). The configuration of compound 3aa was
(SO ) , and Aryldiazonium Tetrafluoroborates 2
2 2
Table 1. Initial Studies for the Reaction of N-Tosyl
Acrylamide 1a, DABCO·(SO ) , and 4-
2
2
a
Methylphenyldiazonium Tetrafluoroborate 2a
b
entry
variation of conditions
yield (%)
1
2
3
4
none
45
21−42
75
trace−71
73
76
67
73
69
66
other copper catalysts instead of Cu(TFA)2
DMF instead of DCE
other solvents instead of DMF
110 °C
50 °C
rt
5 mol % Cu(TFA)2
15 mol % Cu(TFA)2
20 mol % Cu(TFA)2
no Cu(TFA)2
c
5
c
6
c
7
c
,
d
d
8
9
1
1
c
,
a
c
c
,
d
d
Reaction conditions: N-tosyl acrylamide 1a (0.3 mmol), DABCO·
(SO ) (0.45 mmol, 1.5 equiv), aryldiazonium tetrafluoroborates 2a−
0
1
,
trace
2 2
a
s (0.45 mmol, 1.5 equiv), Cu(TFA)
2
(0.015 mmol, 5 mol %), DMF
Reaction conditions: N-tosyl acrylamide 1a (0.2 mmol), DABCO·
SO ) (0.3 mmol, 1.5 equiv), 4-methylphenyldiazonium tetrafluor-
b
(
1.5 mL), 50 °C, 12 h. Isolated yield based on N-tosyl acrylamide 1a.
(
2
2
oborate 2a (0.3 mmol, 1.5 equiv), Cu(TFA) (0.02 mmol, 10 mol %),
2
b
DMF (1.0 mL), 80 °C, 12 h. Isolated yield base on N-tosyl
products 3aa−ap in 51−86% yields. A range of functional
c
d
acrylamide 1a. DMF as the solvent. Reaction was performed at 50
groups including CN, NO , CHO, COMe, CO Me, and CF
2
2
3
°C.
were compatible under the conditions. Notably, aryldiazonium
tetrafluoroborates 2q and 2r bearing α- and β-naphthyl groups
were tolerated as well, giving rise to the corresponding
products 3aq and 3ar in 71 and 68% yields, respectively. A
substrate bearing the heterocyclic skeleton (thiophenyl group)
was found to be suitable in this transformation, although the
yield was not satisfactory (27% yield).
confirmed by X-ray crystallography. Further exploration
revealed that other copper catalysts were not as efficient as
Cu(TFA)2 (Table 1, entry 2; for details, see the SI).
Subsequently, various solvents were examined. It was found
that product 3aa was generated in 75% yield when DMF was
employed as the solvent (Table 1, entry 3). However, the
results were inferior when other solvents were used instead of
DMF (Table 1, entry 4; for details, see the SI). We further
evaluated the effect of the reaction temperature. A comparable
yield was obtained when the reaction occurred at 110 or 50 °C
The substrate scope of N-tosyl acrylamides was further
evaluated (Scheme 3). In general, 4-methylphenyldiazonium
tetrafluoroborate 2a well reacted with DABCO·(SO ) and N-
2
2
tosyl acrylamides 1b−j containing a variety of substituents,
producing the corresponding products 3ba−ja in moderate to
good yields (53−88%). Additionally, α- and β-naphthyl-
derived N-tosyl acrylamides were also amenable to the
conditions, providing products 3na and 3oa in 51 and 67%
yields, respectively. To our delight, α-alkyl-substituted
substrates were also effective, leading to compounds 3ka−ma
in 35−70% yields. However, the reaction failed to afford
product 3pa. Methacrylamide was not workable under the
conditions. Additionally, we amplified the model reaction
(Table 1) to a 1.0 mmol scale, and (Z)-β-alkenyl sulfone 3aa
was produced in 77% yield. Moreover, the gram scale showed
that compound 3aa could be formed in 81% yield (1.48 g; see
the Supporting Information).
To clarify the possible reaction pathway, several control
experiments were performed (Scheme 4). It was found that the
addition of 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO)
would hamper the reaction, revealing that this transformation
might proceed through a radical process (Scheme 4, eq 1).
Additionally, arylsulfonyl radical could be captured by ethene-
1,1-diyldibenzene, affording compound 4 in a reasonable yield
(Scheme 4, eqs 2 and 3).
(Table 1, entries 5 and 6). A lower yield was observed when
this transformation was performed at room temperature (67%
yield, Table 1, entry 7). Because these results showed that the
temperature effect was negligible, we reasoned that the
efficiency might be affected by the copper catalyst. Thus the
loading of Cu(TFA) was examined, which showed that 5 mol
2
%
of copper catalyst was optimal (73%, Table 1, entry 8 vs
entries 9 and 10). Only a trace amount of compound 3aa was
obtained without the addition of Cu(TFA) (Table 1, entry
2
1
1). Furthermore, N-acetyl acrylamide, N-benzoyl acrylamide,
and N-Boc acrylamide were examined in this transformation.
However, it was found that these acrylamides were not suitable
under the conditions, and all reaction systems were complex.
Subsequently, we started to explore the substrate scope for
the stereoselective preparation of (Z)-β-alkenyl sulfones
through a reaction of N-tosyl acrylamides 1, 1,4-
diazabicyclo[2.2.2]octane-sulfur dioxide, and aryldiazonium
tetrafluoroborates 2 under copper catalysis. The reaction of
various aryldiazonium tetrafluoroborates 2 was investigated at
the beginning (Scheme 2). As shown in Scheme 2,
aryldiazonium tetrafluoroborates 2 bearing different groups
on the aromatic ring reacted with N-tosyl acrylamide 1a and
DABCO·(SO ) , smoothly leading to the corresponding
On the basis of the previously described control experiments
7
a,9
and related reports,
we presented a plausible reaction
II
pathway (Scheme 5). We speculated that a Cu complex A
2
2
B
https://dx.doi.org/10.1021/acs.orglett.0c02400
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Letter
Scheme 3. Reaction of N-Tosyl Acrylamides 1, DABCO·
aryldiazonium tetrafluoroborate 2 and 1,4-diazabicyclo[2.2.2]-
II
(
SO ) , and 4-Methylphenyldiazonium Tetrafluoroborate
octane-sulfur dioxide. Then, Cu complex A would combine
2
2
a
,
b
III
2
a
with arylsulfonyl radical to furnish Cu intermediate B, which
would undergo a single electron transfer, affording inter-
mediate C. The interconversion of the cationic alkene radical
with the metal center in an intramolecular mode would afford
III
Cu intermediate D. Subsequently, the deprotonation of
III
intermediate D would give rise to Cu intermediate E, which
would then produce the desired (Z)-β-alkenyl sulfone 3 via
reductive elimination and regenerate the copper catalyst to
realize the catalytic cycle.
In conclusion, we have described a straightforward and
stereoselective preparation of (Z)-β-alkenyl sulfones through a
reaction of N-tosyl acrylamides, 1,4-diazabicyclo[2.2.2]octane-
sulfur dioxide, and aryldiazonium tetrafluoroborates under
2
copper catalysis. The direct C(sp )−H arylsulfonylation of
acrylamides using sulfur dioxide as the sulfonyl source in the
presence of copper trifluoroacetate proceeds smoothly, giving
rise to (Z)-β-alkenyl sulfones in good yields. During the
reaction process, excellent regio- and stereoselectivities are
observed. A radical process involving arylsulfonyl radicals is
proposed. With the assistance of tosyl-imide as the directing
group, (Z)-β-alkenyl sulfones are stereoselectively formed.
Moreover, a gram-scale synthesis is presented, which
demonstrates the synthetic practicability of this method.
a
Reaction conditions: N-tosyl acrylamides 1b−p (0.3 mmol),
DABCO·(SO ) (0.45 mmol, 1.5 equiv), 4-methylphenyldiazonium
2
2
tetrafluoroborate 2a (0.45 mmol, 1.5 equiv), Cu(TFA) (0.015 mmol,
5
tosyl acrylamide 1.
2
b
mol %), DMF (1.5 mL), 50 °C, 12 h. Isolated yield based on N-
ASSOCIATED CONTENT
sı Supporting Information
Scheme 4. Control Experiments
■
*
The Supporting Information is available free of charge at
https://pubs.acs.org/doi/10.1021/acs.orglett.0c02400.
Detailed experimental procedures, crystallographic data,
characterization data, and NMR spectra for all
compounds (PDF)
Accession Codes
CCDC 2012716 contains the supplementary crystallographic
data for this paper. These data can be obtained free of charge
via www.ccdc.cam.ac.uk/data_request/cif, or by emailing
data_request@ccdc.cam.ac.uk, or by contacting The Cam-
bridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
AUTHOR INFORMATION
■
Scheme 5. Plausible Mechanism
Corresponding Author
Jie Wu − School of Pharmaceutical and Materials Engineering &
Institute for Advanced Studies, Taizhou University, Taizhou
3
18000, China; State Key Laboratory of Organometallic
Chemistry, Shanghai Institute of Organic Chemistry, Chinese
Academy of Sciences, Shanghai 200032, China; orcid.org/
0
000-0002-0967-6360; Email: jie_wu@fudan.edu.cn
Author
Tonghao Zhu − School of Pharmaceutical and Materials
Engineering & Institute for Advanced Studies, Taizhou
University, Taizhou 318000, China
Complete contact information is available at:
https://pubs.acs.org/10.1021/acs.orglett.0c02400
would be formed initially by the treatment of Cu(TFA)2
Notes
catalyst with N-tosyl acrylamide 1. Meanwhile, an arylsulfonyl
·+
radical and a radical cation DABCO would be produced from
The authors declare no competing financial interest.
C
https://dx.doi.org/10.1021/acs.orglett.0c02400
Org. Lett. XXXX, XXX, XXX−XXX

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pubs.acs.org/OrgLett
Letter
(
2
6) For reviews, see: (a) Rej, S.; Ano, Y.; Chatani, N. Chem. Rev.
020, 120, 1788−1887. (b) Zhao, Q.; Meng, G.; Nolan, S. P.;
Szostak, M. Chem. Rev. 2020, 120, 1981−2048. (c) Wang, C.-S.;
Dixneuf, P. H.; Soule, J.-F. Chem. Rev. 2018, 118, 7532−7585.
d) Shao, Q.; Wu, K.; Zhuang, Z.; Qian, S.; Yu, J.-Q. Acc. Chem. Res.
2020, 53, 833−851. (e) Jiao, K.-J.; Xing, Y.-K.; Yang, Q.-L.; Qiu, H.;
Mei, T.-S. Acc. Chem. Res. 2020, 53, 300−310. (f) Hu, Y.; Zhou, B.;
Wang, C. Acc. Chem. Res. 2018, 51, 816−827. (g) Piou, T.; Rovis, T.
Acc. Chem. Res. 2018, 51, 170−180. (h) Ma, C.; Fang, P.; Mei, T.-S.
ACS Catal. 2018, 8, 7179−7189. (i) Timsina, Y. N.; Gupton, B. F.;
Ellis, K. C. ACS Catal. 2018, 8, 5732−5776. (j) Chen, Z.; Wang, B.;
Zhang, J.; Yu, W.; Liu, Z.; Zhang, Y. Org. Chem. Front. 2015, 2, 1107−
ACKNOWLEDGMENTS
■
We acknowledge the financial support from the National
Natural Science Foundation of China (nos. 21871053 and
́
2
1532001) and the Leading Innovative and Entrepreneur
(
Team Introduction Program of Zhejiang (no. 2019R01005).
REFERENCES
■
(
1) For selected reviews, see: (a) Lyons, T. W.; Sanford, M. S. Chem.
Rev. 2010, 110, 1147−1169. (b) Yeung, C. S.; Dong, V. M. Chem. Rev.
2
011, 111, 1215−1292. (c) Arockiam, P. B.; Bruneau, C.; Dixneuf, P.
F. Chem. Rev. 2012, 112, 5879−5918. (d) Bruckl, T.; Baxter, R. D.;
1
295. (k) Iqbal, S. A.; Pahl, J.; Yuan, K.; Ingleson, M. J. Chem. Soc.
Rev. 2020, 49, 4564−4591. (l) Sambiagio, C.; Schonbauer, D.; Blieck,
R.; Dao-Huy, T.; Pototschnig, G.; Schaaf, P.; Wiesinger, T.; Zia, M.
F.; Wencel-Delord, J.; Besset, T.; Maes, B. U. W.; Schnurch, M. Chem.
Ishihara, Y.; Baran, P. S. Acc. Chem. Res. 2012, 45, 826−839.
̈
(
e) Ackermann, L. Acc. Chem. Res. 2014, 47, 281−295. (f) Kuhl, N.;
Hopkinson, M. N.; Wencel-Delord, J.; Glorius, F. Angew. Chem., Int.
Ed. 2012, 51, 10236−10254. (g) Cho, S. H.; Kim, J. Y.; Kwak, J.;
Chang, S. Chem. Soc. Rev. 2011, 40, 5068−5083. (h) Gutekunst, W.
R.; Baran, P. S. Chem. Soc. Rev. 2011, 40, 1976−1991. (i) McMurray,
L.; O’Hara, F.; Gaunt, M. J. Chem. Soc. Rev. 2011, 40, 1885−1898.
̈
Soc. Rev. 2018, 47, 6603−6743. (m) Mihai, M. T.; Genov, G. R.;
Phipps, R. J. Chem. Soc. Rev. 2018, 47, 149−171. (n) Shan, C.; Zhu,
L.; Qu, L.-B.; Bai, R.; Lan, Y. Chem. Soc. Rev. 2018, 47, 7552−7576.
(
7
8
o) Evano, G.; Theunissen, C. Angew. Chem., Int. Ed. 2019, 58, 7202−
(
1
j) Zhu, T.; Xie, S.; Rojsitthisak, P.; Wu, J. Org. Biomol. Chem. 2020,
8, 1504−1521.
2) (a) Yu, C.-H.; Chou, C.-C.; Lee, D.-Y.; Khoo, K.-H.; Chang, G.-
236. (p) Rej, S.; Chatani, N. Angew. Chem., Int. Ed. 2019, 58, 8304−
329. (q) Dey, A.; Sinha, S. K.; Achar, T. K.; Maiti, D. Angew. Chem.,
(
Int. Ed. 2019, 58, 10820−10843.
D. Biosci. Rep. 2018, 38, BSR20171717. (b) Jones, B. D.; Tochowicz,
A.; Tang, Y.; Cameron, M. D.; McCall, L. I.; Hirata, K.; Siqueira-
Neto, J. L.; Reed, S. L.; McKerrow, J. H.; Roush, W. R. ACS Med.
Chem. Lett. 2016, 7, 77−82. (c) Woo, S. Y.; Kim, J. H.; Moon, M. K.;
Han, S. H.; Yeon, S. K.; Choi, J. W.; Jang, B. K.; Song, H. J.; Kang, Y.
G.; Kim, J. W.; et al. J. Med. Chem. 2014, 57, 1473−1487.
(
7) (a) Feng, C.; Loh, T.-P. Angew. Chem., Int. Ed. 2013, 52, 12414−
12417. (b) Feng, C.; Feng, D.; Luo, Y.; Loh, T.-P. Org. Lett. 2014, 16,
5
956−5959. (c) Song, S.; Lu, P.; Liu, H.; Cai, S.-H.; Feng, C.; Loh,
T.-P. Org. Lett. 2017, 19, 2869−2872. (d) Feng, C.; Feng, D.; Loh, T.-
P. Chem. Commun. 2015, 51, 342−345.
(
8) (a) Huang, Y.; Xu, L.; Yu, F.; Shen, W.; Lu, X.; Ding, L.; Zhong,
(
d) Meadows, D. C.; Sanchez, T.; Neamati, N.; North, T. W.;
Gervay-Hague, J. Bioorg. Med. Chem. 2007, 15, 1127−1137.
e) Dunny, E.; Doherty, W.; Evans, P.; Malthouse, J. P. G.; Nolan,
L.; Zhong, G.; Zhang, J. J. Org. Chem. 2020, 85, 7225−7237.
(b) Song, S.; Liu, H.; Wang, L.; Zhu, C.; Loh, T.-P.; Feng, C. Chin. J.
(
Chem. 2019, 37, 1036−1040. (c) Sun, Y.; Meng, K.; Zhang, J.; Jin, M.;
Huang, N.; Zhong, G. Org. Lett. 2019, 21, 4868−4872. (d) Xia, X.-F.;
Zhu, S.-L.; Hu, Q.; Li, Y.; Xu, X. Tetrahedron 2017, 73, 3529−3535.
D.; Knox, A. J. S. J. Med. Chem. 2013, 56, 6638−6650. (f) Shen, Y.;
Zificsak, C. A.; Shea, J. E.; Lao, X.; Bollt, O.; Li, X.; Lisko, J. G.;
Theroff, J. P.; Scaife, C. L.; Ator, M. A.; Ruggeri, B. A.; Dorsey, B. D.;
Kuwada, S. K. J. Med. Chem. 2015, 58, 1140−1158.
(
e) Liu, H.; Song, S.; Wang, C.-Q.; Feng, C.; Loh, T.-P.
ChemSusChem 2017, 10, 58−61. (f) Liu, C.; Fang, Y.; Wang, S.-Y.;
Ji, S.-J. Org. Lett. 2018, 20, 6112−6116. (g) Xu, L.; Meng, K.; Zhang,
J.; Sun, Y.; Lu, X.; Li, T.; Jiang, Y.; Zhong, G. Chem. Commun. 2019,
(
3) For recent selected examples, see: (a) Bao, W.-H.; Ying, W.-W.;
Xu, X.-D.; Zhou, G.-D.; Meng, X.-X.; Wei, W.-T.; Liu, Y.-Y.; Li, Q.
Tetrahedron Lett. 2019, 60, 55−58. (b) Pramanik, M.; Choudhuri, K.;
Mal, P. Asian J. Org. Chem. 2019, 8, 144−150. (c) Fan, C.-L.; Zhang,
L.-B.; Liu, J.; Hao, X.-Q.; Niu, J.-L.; Song, M.-P. Org. Chem. Front.
5
5, 9757−9760. (h) Wang, S.-G.; Liu, Y.; Cramer, N. Angew. Chem.,
Int. Ed. 2019, 58, 18136−18140.
9) Zheng, D.; Yu, J.; Wu, J. Angew. Chem., Int. Ed. 2016, 55,
1925−11929.
(
1
2
019, 6, 2215−2219. (d) Kramer, P.; Krieg, S.-C.; Kelm, H.;
Manolikakes, G. Org. Biomol. Chem. 2019, 17, 5538−5544. (e) Liang,
X.; Xiong, M.; Zhu, H.; Shen, K.; Pan, Y. J. Org. Chem. 2019, 84,
1
1210−11218. (f) Wang, X.; Hu, B.; Yang, P.; Zhang, Q.; Li, D.
Tetrahedron 2020, 76, 131082. (g) Mulina, O. M.; Zhironkina, N. V.;
Paveliev, S. A.; Demchuk, D. V.; Terent’ev, A. O. Org. Lett. 2020, 22,
1
(
818−1824.
4) For reviews, see: (a) Liu, G.; Fan, C.-B.; Wu, J. Org. Biomol.
Chem. 2015, 13, 1592−1599. (b) Emmett, E. J.; Willis, M. C. Asian J.
Org. Chem. 2015, 4, 602−611. (c) Zheng, D.; Wu, J. Sulfur Dioxide
Insertion Reactions for Organic Synthesis; Nature Springer: Berlin, 2017.
(
6
d) Qiu, G.; Zhou, K.; Gao, L.; Wu, J. Org. Chem. Front. 2018, 5,
91−705. (e) Huang, M.-H.; Hao, W.-J.; Jiang, B. Chem. - Asian J.
018, 13, 2958−2977. (f) Huang, M.-H.; Hao, W.-J.; Li, G.-G.; Tu,
2
S.-J.; Jiang, B. Chem. Commun. 2018, 54, 10791−10811. (g) Hofman,
K.; Liu, N.-W.; Manolikakes, G. Chem. - Eur. J. 2018, 24, 11852−
1
5
2
2
2
1863. (h) Qiu, G.; Lai, L.; Cheng, J.; Wu, J. Chem. Commun. 2018,
4, 10405−10414. (i) Qiu, G.; Zhou, K.; Wu, J. Chem. Commun.
018, 54, 12561−12569. (j) Ye, S.; Qiu, G.; Wu, J. Chem. Commun.
019, 55, 1013−1019. (k) Ye, S.; Yang, M.; Wu, J. Chem. Commun.
020, 56, 4145−4155.
(
5) (a) Fan, W.; Su, J.; Shi, D.; Feng, B. Tetrahedron 2015, 71,
6
740−6743. (b) Mao, R.; Yuan, Z.; Zhang, R.; Ding, Y.; Fan, X.; Wu,
J. Org. Chem. Front. 2016, 3, 1498−1502. (c) He, F.-S.; Gong, X.;
Rojsitthisak, P.; Wu, J. J. Org. Chem. 2019, 84, 13159−13163.
(
d) Zhu, T.-H.; Zhang, X.-C.; Zhao, K.; Loh, T.-P. Org. Chem. Front.
2
019, 6, 94−98. (e) Zhu, T.-H.; Zhang, X.-C.; Cui, X.-L.; Zhang, Z.-
Y.; Jiang, H.; Sun, S.-S.; Zhao, L.-L.; Zhao, K.; Loh, T.-P. Adv. Synth.
Catal. 2019, 361, 3593−3598.
D
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