Cs2CO3-Mediated Vicinal Thiosulfonylation of 1,1-Dibromo-1-Alkenes with Thiosulfonates: An Expedient Synthesis of (E)-1,2-Thiosulfonylethenes

Article abstract of DOI:10.1002/adsc.201801620

A new and highly efficient vicinal thiosulfonylation of 1,1-dibromo-1-alkenes with thiosulfonates in the presence of cesium carbonate has been developed. The metal-free diheterofunctionalization is an operationally simple to access a wide range of (E)-1,2-thiosulfonylethenes (α-aryl-β-thioarylvinyl sulfones) in moderate to high yields with high levels of stereoselectivities. Further, scalable reactions have been demonstrated for this transformation, thus illustrating its efficiency and practicality. (Figure presented.).

Full text of DOI:10.1002/adsc.201801620

Title: Cs2CO3-mediated vicinal thiosulfonylation of 1,1-dibromo-1-
alkenes with thiosulfonates: An expedient synthesis of (E)-1,2-
thiosulfonylethenes
Authors: Raju Jannapu Reddy, Haritha Kumari Arram , Jagadesh
Kumar Jangam , and Jagadeesh Babu Nanubolu
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To be cited as: Adv. Synth. Catal. 10.1002/adsc.201801620
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10.1002/adsc.201801620
Advanced Synthesis & Catalysis
COMMUNICATION
DOI: 10.1002/adsc.201((will be filled in by the editorial staff))
Cs2CO3Mediated Vicinal Thiosulfonylation of 1,1-Dibromo-1-
Alkenes with Thiosulfonates: An Expedient Synthesis of (E)-1,2-
Thiosulfonylethenes
Raju Jannapu Reddy,*,a Arram Haritha Kumari,†,a Jangam Jagadesh Kumar†,a and
Jagadeesh Babu Nanubolub
a
Department of Chemistry, University College of Science, Osmania University, Hyderabad 500 007, India.
Centre for X-ray Crystallography, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
b
E-mail: rajuchem77@osmania.ac.in; rajuchem08@yahoo.co.in
† These authors contributed equally.
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))
thiosulfonylation of alkenes in an atom-economical
Abstract.
A
new and highly efficient vicinal
thiosulfonylation of 1,1-dibromo-1-alkenes with
thiosulfonates in the presence of cesium carbonate has
been developed. The metal-free diheterofunctionalization
is an operationally simple to access a wide range of (E)-
1,2-thiosulfonylethenes (-aryl--thioarylvinyl sulfones)
in moderate to high yields with high levels of
stereoselectivities. Further, scalable reactions have been
demonstrated for this transformation, thus illustrating its
efficiency and practicality.
manner (Scheme 1a).[8a] Later on, Li et al. elegantly
reported
a
gold/photoredox-cocatalyzed vicinal
thiosulfonylation of alkynes using PhSO2SR (R = CF3
and CF2H) as a diheterofunctionalization reagent
(Scheme 1b).[8b] Very recently, Li group employed a
copper-catalyzed decarboxylative disulfonylation of
alkynyl carboxylic acids with sulfinic acids to form
(E)-1,2-disulfonylethenes (Scheme 1c).[4b] These
approaches usually require an expensive metal
catalyst(s), excess use of oxidants and inaccessible
starting materials.
Keywords:
Diheterofunctionalization;
gem-
Dibromoalkenes; Thiosulfonylation; Thiosulfonates;
Vinyl sulfones
Difunctionalization of alkenes and alkynes offers a
powerful platform for the rapid construction of
molecular complexity from simple starting
materials.[1] Significant attention has been devoted for
the installation of diverse functional groups onto
vicinal carbons of alkene moieties to form two new
chemical bonds in a single operation.[2-4] Despite
substantial progress has been made toward vicinal
difunctionalization of olefins, the reactions toward
1,2-diheterofunctionalizations of alkenes and
successively persist of the alkene moiety has not been
explored.
Among a variety of organosulfur compounds,[5]
thiosulfonates (RS–SO2R1) are the privileged class of
compounds in synthetic organic chemistry.[6-8]
Generally, thiosulfonates were demonstrated as a
electrophilic sulfenylating reagent, which often
discard the sulfonyl moiety as a waste.[4a,7] Recently,
the diverse reactivity of thiosulfonates have been
discovered as a 1,1- or 1,2-thiosulfonylating agent.[8]
However, the installation of two distinct C–S bonds
via 1,2-thiosulfonylation has rarely been explored.[8a,b]
Scheme 1. Pattern for vicinal C–S bonds construction.
In spite of these achievements, assembling highly
substituted alkenes in a rapid, flexible and efficient
manner that also accommodates diverse functional
groups remains a challenge. We envisioned that 1,1-
dibromo-1-alkene could be right starting material for
installation of two different C–S bonds and
concurrently retaining the C–C double bond in a
single synthetic operation. Therefore, we wanted to
In this context, Xu and co-workers developed
a
combination of gold and photoredox catalytic
approach for an intermolecular atom transfer
1
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10.1002/adsc.201801620
Advanced Synthesis & Catalysis
investigate the vicinal thiosulfonylation of 1,1-
dibromo-1-alkenes with thiosulfonates to construct
1,2-thiosulfonylethenes (Scheme 1d). In fact, gem-
dihaloolefins are often used as alkyne precursors and
their rich chemistry has been extensively explored.[9]
In continuous of our interest on organosulfur
chemistry,[10] herein, we report an efficient and
unprecedented Cs2CO3-mediated intermolecular
vicinal thiosulfonylation of 1,1-dibromo-1-alkenes
with thiosulfonates to give (E)-1,2-thiosulfonyl-
ethenes.
Table 1. Optimization of vicinal thiosulfonylation using
1,1-dibromoalkene 1a with S-phenyl thiosulfonate 2a.[a]
Time Conv[b]
Entry
1
Base (eq.)
E/Z[c]
16/1
15/1
16/1
---
18/1
18/1
18/1
18/1
16/1
---
Solvent
DMF
DMSO
DMA
At outset, our investigations commenced with 4-
(2,2-dibromovinyl)-1,2-dimethoxybenzene 1a and S-
Cs2CO3 (2 eq.)
Cs2CO3 (2 eq.)
Cs2CO3 (2 eq.)
5 h
5 h
5 h
5 h
4 h
3 h
3 h
4 h
3 h
5 h
5 h
59%
49%
53%
10%
75%
81%
78%
70%
72%
trace
trace
23%
2
3
4
5
6
7
phenyl benzenesulfonothioate 2a as
a model
substrates. Initial experiments were performed with
copper-catalyzed thiosulfonylation of 1a with 2a in
the presence of Cs2CO3 to give moderate to good
yields for the desired product 3aa (see the SI for a
detailed survey of reaction conditions). Surprisingly,
Cs2CO3 alone afforded the thiosulfonylated product
3aa (Table 1). The reaction of 1a with 1.5 equiv of 2a
in the presence of Cs2CO3 (2 equiv) in DMF, DMSO
Toluene Cs2CO3 (2 eq.)
DMF
DMF
DMF
DMF
DMF
DMF
DMF
DMF
Cs2CO3 (3 eq.)
Cs2CO3 (4 eq.)
Cs2CO3 (5 eq.)
Cs2CO3 (4 eq.)
Cs2CO3 (4 eq.)
K2CO3 (4 eq.)
DBU (4 eq.)
8[d]
9[e]
10
11
12
o
and DMA (Dimethylacetamide) at 90 C afforded
---
16/1
modest conversion (entries 1-3) and a low conversion
in toluene (entry 4) was observed. A substantial
progress was seen by increasing the amount of
Cs2CO3 (entries 5 and 6); the best conversion and high
stereoselectivity was achieved with 4 equiv of Cs2CO3
(entry 6). Our attempts were failed to improve the
conversion by varying the amounts of Cs2CO3,
concentration and temperature (entries 7-9). No
reaction took place in the presence of K2CO3 and
DBU (entries 10 and 11), however, a low conversion
was observed with DABCO (entry 12).
DABCO (4 eq.) 5 h
[a] All reactions performed on a 0.2 mmol scale of 1a (1.0
eq.), 2a (1.5 eq.) and base (2 to 5 eq.) in 1.0 mL of solvent
o
[b,c]
1
at 90 C.
Yields and E/Z mixture based on H NMR
analysis using 1,2,4,5-tetramethyl benzene as an internal
standard. [d] The reaction carried out in 2 mL of DMF. [e] At
110 oC.
Table 2. Substrate scope for vicinal thiosulfonylation.[a,b]
Encouraged by these results, we next proceeded to
explore the generality of the reaction under the
optimized reaction conditions (Table 2). A series of
gem-dibromoalkenes (1a-p) employed for 1,2-
thiosulfonylation
with
S-phenyl
benzene-
sulfonothioate 2a to afford the corresponding (E)-1,2-
thiosulfonylethenes 3(a-p)a in 42-91% yields with
excellent stereoselectivities. Notably, both electron-
withdrawing and electron-donating groups on the
aromatic ring of 1 were compatible under same
reaction conditions. However, the nature and position
of the substituents had little influence on the outcome
(cf. 3ca, 3da, 3ga-ja) of the transformation. The
structure and alkene geometry of 3ca was further
confirmed by single crystal X-ray data analysis (see
SI).[11,12]
Remarkably,
heteroaryl
derived
dibromoalkenes 1k and 1l were also well-tolerated
under the standard conditions, leading to the desired
products 3ka and 3la in 74% and 67% yields,
respectively. The naphthyl derived products (3ma and
3na) were obtained in high yields under the reaction
conditions, whereas sterically bulky dibromoalkene
1o afforded the desired vinyl sulfone in 42% yield
only. In contrast, cinnamyl derived dibromoolefin 1p
gave the corresponding product with an inseparable
mixture of other unidentified products.
[a]
All reactions were performed a 0.5 mmol scale of 1a-p
(1.0 eq.), 2a (1.5 eq.) and Cs2CO3 (4.0 eq.) in anhydrous
DMF (2.5 mL) under N2 at 90 oC for 3 h. [b] Isolated yield.
[c] E/Z mixture based on 1H NMR analysis.
Furthermore, we sought to evaluate the scope of
symmetrical and unsymmetrical thiosulfonates (2b-g).
2
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10.1002/adsc.201801620
Advanced Synthesis & Catalysis
Various thiosulfonates were explored in vicinal
thiosulfonylation and smoothly furnished the (E)-1,2-
thiosulfonylethene products in good to high yields
(Table 3). As expected symmetrical thiosulfonates
(2b and 2d) reacted well with representative gem-
dibromoolefins with no apparent effect on the resulted
products. The use of unsymmetrical thiosulfonates (2c
and 2e) has a considerable influence on the
stereoselectivity, which provided thiosulfonylated
products (cf: 3ac, 3be, 3kc, 3ke, 3mc and 3me) in
satisfactory yields. The reaction of 1a with 4-chloro
derived thiosulfonate 2f gave the corresponding
product 3af in a trace amount, albeit thiosulfonate 2g
was not a suitable substrate for this transformation. It
is worth to note that these multifunctional vinyl
sulfones are potentially valuable compounds in
organic and medical chemistry.[13]
dibromoenamides were degraded under the optimal
reaction conditions. However, the reactions at room
temperature proceeded sluggishly to form the desired
products 5a and 5b in trace amounts (Scheme 2).
Scheme 2. Reactions were performed on a 0.5 mmol scale
of 4a/b (1.0 eq.), 2a (1.5 eq.) and Cs2CO3 (4.0 eq.) in
anhydrous DMF (2.5 mL) at 90 oC or at room temperature.
To demonstrate the synthetic utility of this protocol,
a gram-scale reaction was carried out under the
optimization reaction conditions. As shown in
Scheme 3, a 4 mmol scale reactions of 1,1-
dibormoalkenes (1a/b) with S-phenyl benzene-
sulfonothioate 2a were performed to produce 1.19 g
(72%) of 3aa and 1.15 g (65%) of 3ba, thus
demonstrated the thiosulfonylation could be readily
scalable with a slight deviation on efficiency.
Table 3. Substrate scope for vicinal thiosulfonylation.[a,b]
Scheme 3. Gram-scale reaction for thiosulfonyaltion.
To gain valuable insight to understanding the
reaction mechanism, several control experiments
were performed for 1,2-thiosulfonylation (Scheme 4).
A mixture of products 3ab and 3ac were detected by
1H NMR, when standard reaction employed with 2b
and sodium benzenesulfinate, thus implying both the
thiosulfonates might be competing in the
transformation (Scheme 4a). The thiosulfonate 1c
(PhSO2STolyl) would be generated in situ by the
reaction between 2b with sodium benzenesulfinate,
which might be accountable in the formation of 3ac.
A radical scavenger TEMPO (2,2,6,6-tetramethyl-1-
piperidinyloxy) was added to the standard reaction.
With 4.0 equiv. of TEMPO inhibition of the reaction
was observed and 3aa was obtained in only 12% yield
(Scheme 4b). However, the reaction was totally
inhibited with 6.0 equiv. of TEMPO (Scheme 4b).
Further, no reaction was found without Cs2CO3 and
also both the reactants were not affected in the
presence of TEMPO (Scheme 4c). Next, the reaction
between 1a and 2a under standard conditions in
deuterated DMF (DMF-d7) aff orded 3aa in 52%
yield without any deuterium incorporation at olefin
carbon (Scheme 4d). The terminal alkyne (6) yielded
the desired product 3aa in traces (Scheme 4e),
however, the 1-bromoalkyne (7)[9a] was smoothly
transformed into the corresponding product 3aa in
38% yield under the standard condition (Scheme 4f).
Additionally, thioalkyne (8)[9h,14] failed to react with
[a] All reactions were performed on a 0.5 mmol scale
of 1 (1.0 eq.), 2b-g (1.5 eq.) and Cs2CO3 (4.0 eq.) in
anhydrous DMF (2.5 mL) under N2 at 90 oC for 3-5 h.
[b]
1
Isolated yield. [c] E/Z mixture based on H NMR
analysis.
Next, the scope of vicinal thiosulfonylation
reaction can extend to more valuable substrates.
Accordingly, we verified vinyl dibromoenamides
(4a/b) with thiosulfonate 2a for diverse substitution
pattern on the products. Disappointingly, these
3
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10.1002/adsc.201801620
Advanced Synthesis & Catalysis
either with 2a or with sodium benzenesulfinate in the
presence of iodine to give 3aa (Scheme 4g). Overall,
these results suggested that the 1-bromoalkyne 7
might be responsible for this transformation.
synthetic applications of 1,2-thiosulfonylethenes and
more mechanistic studies are currently underway.
Experimental Section
A heat gun-dried Schlenk tube was charged 1,1-dibromo-
1-alkenes 1 (0.5 mmol, 1.0 eq.), thiosulfonates 2 (0.75
mmol, 1.5 eq.) and Cs2CO3 (2.0 mmol, 4.0 eq.) in DMF (2.5
o
mL). The reaction mixture was stirred at 90 C for 3 h and
monitored by TLC either complete or appeared to be
proceeding no further progress. The mixture was quenched
by addition of water (10 mL) followed by extraction with
EtOAc (3x10 mL). The combined organic layers was
washed with brine (2x10 mL), dried over anhydrous
Na2SO4, and the solvent was removed under reduced
pressure. The resulting residue was subjected to silica gel
flash chromatography to afford the desired (E)-1,2-
thiosulfonylethenes 3.
Acknowledgements
We thank SERB-ECR (File No. ECR/2015/000053) and UGC-
Start-up grant (F.4-5/2006/BSR), New Delhi for financial
assistance. RJR thanks to UGC for faculty position under Faculty
Recharge Programme. JJK thanks to DST Inspire, New Delhi for
his research fellowship.
References
[1] Reviews on difunctionalization of alkenes and alkynes,
see; a) G. Yin, X. Mu, G. Liu, Acc. Chem. Res. 2016,
49, 2413; b) T. Courant, G. Masson, J. Org. Chem. 2016,
81, 6945; c) X.-W. Lan, N.-X. Wang, Y. Xing, Eur. J.
Org. Chem. 2017, 39, 5821; d) V. P. Boyarskiy, D. S.
Ryabukhin, N. A. Bokach, A. V. Vasilyev, Chem. Rev.
2016, 116, 5894; e) M. B. Ansell, O. Navarro, J.
Spencer, Coord. Chem. Rev. 2017, 336, 54; f) G. S.
Sauer, S. Lin, ACS Catal. 2018, 8, 5175; g) X. Wu, S.
Wu, Z. Chen, Tetrahedron Lett. 2018, 59, 1328.
Scheme 4. Control experiments.
[2] Recent reports on radical 1,2-dicarbofunctionalization:
a) B. Shrestha, P. Basnet, R. K. Dhungana, KC. Shekhar,
S. Thapa, J. M. Sears, R. Giri, J. Am. Chem. Soc. 2017,
139, 10653; b) L. Wu, F. Wang, X. Wan, D. Wang, P.
Chen, G. Liu, J. Am. Chem. Soc. 2017, 139, 2904; c) A.
Garcia-Dominguez, Z. Li, C. Nevado, J. Am. Chem. Soc.
2017, 139, 6835; d) X. H. Ouyang, R. J. Song, M. Hu,
Y. Yang, J. H. Li, Angew. Chem. Int. Ed. 2016, 55, 3187.
On the basis of above results and the literature
precedents[4c,8a,b,9e-j]
,
the transformation should
proceed through a radical pathway. On the other hand,
the thermal homolytic cleavage of thiosulfonate 2a
was known to generate a sulfonyl and a sulfenyl
radical species.[15,16] Although several
control
experiments have been performed for vicinal
thiosulfonylation, yet the reaction mechanism is still
not clear. However, a very plausible (tentative)
mechanism was proposed in the supporting
information to rationalize the experimental outcome
and the control experiments.
[3] Selected few examples on 1,2-carbohetero-
functionalization: a) Y. Cheng, C. Mꢀck-Lichtenfeld, A.
Studer, J. Am. Chem. Soc. 2018, 140, 6221; b) H.-Y.
Zhang, C. Ge, J. Zhao, Y. Zhang, Org. Lett. 2017, 19,
5260; c) D. Wang, L. Wu, F. Wang, X. Wan, P. Chen,
Z. Lin, G. Liu, J. Am. Chem. Soc. 2017, 139, 6811; d)
A. Tlahuext-Aca, R. A. Garza-Sanchez, F. Glorius,
Angew. Chem. Int. Ed. 2017, 56, 3708; e) Y. Y. Liu, X.-
H. Yang, R.-J. Song, S. Luo, J.-H. Li, Nat. Commun.
2017, 8, 14720; f) Y. F. Cheng, X. Y. Dong, Q. S. Gu,
Z. L. Yu, X. Y. Liu, Angew. Chem. Int. Ed. 2017, 56,
8883; g) A. Bunescu, T. M. Wang, Q. Ha, J. Zhu,
Angew. Chem. Int. Ed. 2017, 56, 10555.
In conclusion, we have successfully developed a
novel Cs2CO3mediated vicinal thiosulfonylation of
1,1-dibromo-alkenes with thiosulfonates under mild
reaction conditions. Utilization of readily available
starting materials provided an efficient and practical
approach to form a variety of (E)-1,2-thiosulfo-
nylethenes with high levels of stereoselectivities. The
transformation is established by its wide substrate
scope and reliable at the gram-scale reactions. The
[4] Selected reports on 1,2-diheterofunctionalization: a) W.
Kong, C. Yu, H. An, Q. Song, Org. Lett. 2018, 20, 4975;
4
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10.1002/adsc.201801620
Advanced Synthesis & Catalysis
b) H. Fu, J.-Q. Shang, T. Yang, Y. Shen, C.-Z. Gao, Y.-
Liu, Y. Zhao, J. Org. Chem. 2014, 79, 3678; f) K.
Jouvin, A. Coste, A. Bayle, F. Legrand, G. Karthikeyan,
K. Tadiparthi, G. Evano, Organometallics 2012, 31,
7933; g) H. Xu, S. Gu, W. Chen, D. Li, J. Dou, J. Org.
Chem. 2011, 76, 2448; h) Z. Ni, S. Wang, H. Mao, Y.
Pan, Tetrahedron Lett. 2012, 53, 3907; i) M. Zhao, C.
Kuang, Q. Yang, X. Cheng, Tetrahedron Lett. 2011, 52,
992; j) H. Jin, Y. Yang, C. Kuang, Q. Yang, Synlett.
2011, 2886; For a review, see: k) G. Chelucci, Chem.
Rev. 2012, 112, 1344.
M. Li, Org. Lett. 2018, 20, 489; c) C. Dai, J. Wang, S.
Deng, C. Zhou, W. Zhang, Q. Zhu, X. Tang, RSC Adv.
2017, 7, 36112; d) Y. Yang, R.-J. Song, X.-H. Ouyang,
C.-Y. Wang, J.-H. Li, S. Luo, Angew. Chem. Int. Ed.
2017, 56, 7916; e) I. G. Molnár, R. Gilmour, J. Am.
Chem. Soc. 2016, 138, 5004; f) X. Sun, X. Li, S. Song,
Y. Zhu, Y.-F. Liang, N. Jiao, J. Am. Chem. Soc. 2015,
137, 6059; g) J. L. Jat, M. P. Paudyal, H. Gao, Q.-L. Xu,
M. Yousufuddin, D. Devarajan, D. H. Ess, L. Kꢀrti, J.
R. Falck, Science 2014, 343, 61.
[10] a) R. J. Reddy, Md. Waheed, T. Karthik, A. Shankar,
New J. Chem. 2018, 42, 980; b) R. J. Reddy, A. Shankar,
Md. Waheed, J. B. Nanubolu, Tetrahedron Lett. 2018,
59, 2014; c) R. J. Reddy, Md. Waheed, J. J. Kumar, RSC
Adv. 2018, 8, 40446.
[5] Recent leading articles: a) C.-F. Lee, R. S. Basha and S.
S. Badsara, Top. Curr. Chem. 2018, 376, 25; b) K. L.
Dunbar, D. H. Scharf, A. Litomska and C. Hertweck,
Chem. Rev. 2017, 117, 5521; c) X.-H. Xu, K. Matsuzaki,
N. Shibata, Chem. Rev. 2015, 115, 731; d) C. Ni, M. Hu,
J. Hu, Chem. Rev. 2015, 115, 765; e) C.‐ F. Lee, Y.‐ C.
Liu, S. S. Badsara, Chem.-Asian J. 2014, 9, 706; f)
Organosulfur Chemistry I & II, (Ed.: P. C. B. Page),
Springer, Berlin, 1999.
[11] The single X-ray crystal structure (CCDC 1872991)
contain the supplementary crystallographic data for
compound 3ca. These data can be obtained free of
charge from the Cambridge Crystallographic Data
Centre.
[6] A review on thiosulfonates, see: N. S. Zefirof, N. V.
Zyk, E. K. Beloglazkina, A. G. Kutateladze, Sulfur Rep.
1993, 14, 223.
[12] A few crystals were picked up carefully and
characterised by 1H NMR analysis. The mixture
substantially improved to 18:1 (original ratio is 12:1),
which revealed the crystals should be major (E-isomer)
isomer (see SI).
[7] a) Y. Fang, T. Rogge, L. Ackermann, S.-Y. Wang and
S.-J. Ji, Nat. Commun. 2018, 9, 2240; b) A. D. Gillie, R.
J. Reddy, P. W. Davies, Adv. Synth. Catal. 2016, 358,
226; c) K. Kanemoto, Y. Sugimura, S. Shimizu, S.
Yoshida, T. Hosoya, Chem. Commun., 2017, 53, 10640;
d) W. Wang, X. Peng, F. Wei, C.-H. Tung, Z. Xu,
Angew. Chem. Int. Ed. 2016, 55, 649; e) S. Yoshida, Y.
Sugimura, Y. Hazama, Y. Nishiyama, T. Yano, S.
Shimizu, T. Hosoya, Chem. Commun. 2015, 51, 16613;
f) P. Mampuys, Y. Zhu, T. Vlaar, E. Ruijter, R. V. A.
Orru, B. U. W. Maes, Angew. Chem. Int. Ed. 2014, 53,
12849.
[13] a) X.-Q. Pan, J.-P. Zou, W.-B. Yi, W. Zhang,
Tetrahedron 2015, 71, 7481; b) Y. Fang, Z. Luo, X. Xu,
RSC Adv. 2016, 6, 59661; c) D. C. Meadows, J. Gervay-
Hague, Med. Res. Rev. 2006, 26, 793.
[14] For thioalkynes, see: a) R. J. Reddy, M. P. Ball-Jones,
P. W. Davies, Angew. Chem. Int. Ed. 2017, 56, 13310;
b) W. Song, N. Zheng, M. Li, K. Dong, J. Li, K. Ullah,
Y. Zheng, Org. Lett. 2018, 20, 6705.
[15] a) P. K. Shyam, H.-Y. Jang, J. Org . Chem. 2017, 82,
1761; b) P. K. Shyam, S. Son, H.-Y. Jang, Eur. J. Org.
Chem. 2017, 5025.
[8] a) H. Li, C. Shan, C.-H. Tung, Z. Xu, Chem. Sci. 2017,
8, 2610; b) H. Li, Z. Cheng, C.-H. Tung, Z. Xu, ACS
Catal. 2018, 8, 8237; c) C. Rao, S. Mai, Q. Song, Chem.
Commun., 2018, 54, 5964; d) S. Huang, N. Thirupathi,
C.-H. Tung and Z. Xu, J. Org. Chem., 2018, 83, 9449;
e) H. Yuan, N. Thirupathi, H. Gao, C.-H. Tung, Z. Xu,
Org. Chem. Front. 2018, 5, 1371.
[16] Homolytic cleavage of thiosulfonates by EPR studies,
see: a) B. C. Gilbert, B. Gill, M. D. Sexton, J. Chem.
Soc., Chem. Commun. 1978, 78; b) C. Chatgilialoglu, B.
C. Gilbert, B. Gill, M. D. Sexton, J. Chem. Soc., Perkin
Trans. 2, 1980, 1141.
[9] a) S. K. Moodapelly, G. V. M. Sharma, V. R. Doddi,
Adv. Synth. Catal. 2017, 359, 1535; b) A. Srivastava, L.
Aggarwal, N. Jain, ACS Comb. Sci. 2015, 17, 39; c) A.
K. Morri, Y. Thummala, V. R. Doddi, Org. Lett. 2015,
17, 4640; d) G. Chelucci, Chem. Commun. 2014, 50,
4069; e) Y. Wang, J. Gan, L. Liu, H. Yuan, Y. Gao, Y.
5
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10.1002/adsc.201801620
Advanced Synthesis & Catalysis
COMMUNICATION
Cs2CO3Mediated Vicinal Thiosulfonylation of 1,1-
Dibromo-1-Alkenes with Thiosulfonates: An
Expedient Synthesis of (E)-1,2-Thiosulfonylethenes
Adv. Synth. Catal. Year, Volume, Page – Page
Raju Jannapu Reddy,* Arram Haritha Kumari,
Jangam Jagadesh Kumar and Jagadeesh Babu
Nanubolu
6
This article is protected by copyright. All rights reserved.