Interception of benzyne with thioethers: A facile access to sulfur ylides under mild conditions

Article abstract of DOI:10.1039/c3ra47206j

Reactive benzyne generated from o-(trimethylsilyl)phenyl triflate under the action of CsF has been trapped in situ by thioethers to give sulfonium ylides, which in turn have been intercepted by isatins to give rise to corresponding spiroepoxy oxindoles in moderate to high yields. This reaction provides a facile and efficient synthesis of spiroepoxy oxindoles.

Full text of DOI:10.1039/c3ra47206j

RSC Advances
View Article Online
View Journal | View Issue
COMMUNICATION
Interception of benzyne with thioethers: a facile
access to sulfur ylides under mild conditions†
Cite this: RSC Adv., 2014, 4, 7623
Hua-Dong Xu,*ab Mao-Qiang Cai, Wei-Jie He, Wen-Hao Hu and Mei-Hua Shen*
a
a
a
b
Received 2nd December 2013
Accepted 8th January 2014
DOI: 10.1039/c3ra47206j
www.rsc.org/advances
12
Reactive benzyne generated from o-(trimethylsilyl)phenyl triflate intramolecular 1,4-proton shi (Method C, Fig. 1) has been
under the action of CsF has been trapped in situ by thioethers to give almost totally neglected since its debut, wherein the o-uo-
sulfonium ylides, which in turn have been intercepted by isatins to give rophenylmagnesium bromide was employed as the benzyne
13
rise to corresponding spiroepoxy oxindoles in moderate to high yields. precursor, as few further investigations have followed. The
This reaction provides a facile and efficient synthesis of spiroepoxy poor compatibility of these protocols with some common
oxindoles.
functional groups seriously limited their applications.
Recent ourishing advances in the area of aryne chemistry
have brought new reactivities and applications to these highly
1
Since being discovered in 1930, sulfonium ylides have been
involved in various transformations, such as epoxidation of
aldehydes/ketones, aziridination of imines, cyclopropanation
14
reactive intermediates. This resurgence in aryne chemistry is
attributed largely to the introduction of o-(trimethylsilyl)aryl
triates, by Kobayashi et al., as convenient and efficient aryne
precursors that require only very mild conditions (weakly basic
2
3
2
c,4
of conjugated enones/enoates and their congeners, as well as
5
2,3-Wittig rearrangement of allylic/propargyl sulfonium ylides,

uoride anion source and ambient temperature) to promote the
providing invaluable synthetic methods. Recently, Aggarwal
group has made great advances in sulfonium ylide mediated
catalytic asymmetric epoxidation. The Tang laboratory has also
15
in situ formation of corresponding arynes. We therefore
decided to use o-(trimethylsilyl)aryl triate to revisit the thio-
ether/benzyne strategy of sulfonium ylide formation, hoping to
develop new synthetic processes. Here we report a convenient
6
achieved a series of excellent asymmetric Michael addition/
4c,7
cyclization cascades triggered by sulfonium ylides; moreover
Xiao and colleagues have disclosed several efficient heterocyclic
synthesis featuring formal [4 + 1] cycloaddition on sulfonium
16
one-pot synthesis of epoxyoxindoles via this thioether/benzyne
strategy.
We chose cinnamyl p-tolyl sulde (2a) and N-methyl isatin (3a)
as benzyne interceptor and sulfonium ylide interceptor respec-
8
ylides. Although there exist a handful of methods for sulfo-
9
nium ylide formation, deprotonation of corresponding sulfo-
nium salts constitutes the major avenue to the ylide formation
due to their inherent benets (Method A, Fig. 1). Reaction of
thioethers with carbenes/metal carbenoids constitutes a second
consequential approach which has found broad applications
17
tively to test this strategy. Thus a mixture of 1, 2a, and 3a with
cesium uoride (1/2a/3a/CsF : 1.2/1.5/1.0/3.0) in anhydrous
1
0
1
0a,11
(Method B, Fig. 1).
Another elegant yet undeveloped
strategy for sulfonium ylide formation, namely, nucleophilic
attack of alkyl thioether on benzyne followed by an
a
Shanghai Engineering Research Centre of Molecular Therapeutics and New Drug
Development, East China Normal University, Shanghai, 200062, China. E-mail:
huadongxu@gmail.com; Tel: +86 021-62221237
b
School of Pharmaceutical Engineering and Life Science, Changzhou University,
Changzhou, Jiangsu Province, 213164, China. E-mail: meihuashen@gmail.com; Fax:
+
86 0519-86334598; Tel: +86 0519-86334597
†
Electronic supplementary information (ESI) available: General experimental
1
information, detailed procedures, characterize data of compounds, copies of
H
13
and C NMR spectra for selected compounds. See DOI: 10.1039/c3ra47206j
Fig. 1 Three strategies to generate sulfonium ylide.
RSC Adv., 2014, 4, 7623–7626 | 7623
This journal is © The Royal Society of Chemistry 2014

View Article Online
RSC Advances
Communication
a
acetonitrile was vigorously stirred overnight at room tempera- Table 2 Substituent effects on isatin aromatic ring
ture. A pair of diastereoisomers (cis-4a and trans-4a) was isolated
in 25% yield, and the by-product phenyl tolyl thioether 5a was
also collected and identied. These observations conrmed our
proposal. Brief screening of solvents quickly distinguished
acetonitrile as a better reaction medium than other solvents such
as tetrahydrofuran, ethyl acetate, N,N-dimethylformamide and
dichloromethane. Further optimization was carried out in
acetonitrile and the results were shown in Table 1. When the
ꢀ
b
c
reaction mixture was stirred overnight at 40 C, the epoxide Entry
Istatin 3, R
Product 4 yield %
Dr (cis : trans)
isomers 4aa was obtained in 87% yield (entry 2), much higher
than both at 25 C (entry 3, 68%) and at 80 C (entry 4, 41%). With
ꢀ
ꢀ
1
2
3
4
5
6
7
8
9
1
3a, H
3b, 5-CH
4aa, 87
4ab, 50
4ac, 32
4ad, 36
4ae, 58
4af, 93
4ag, 84
4ah, 64
4ai, 42
4aj, 31
4ak, 70
44 : 56
54 : 46
59 : 41
53 : 47
43 : 57
33 : 67
45 : 55
76 : 24
45 : 55
43 : 57
49 : 51
3
the isatin 3a as limiting reagent, the reaction gave diastereomers
3c, 5-OMe
3d, 5-Br
3e, 5-Cl
3f, 5-F
3g, 5-NO
3h, 4-Br
3i, 6-Cl
3j, 6-F
ꢀ
4
aa in 68% yield at 40 C (entry 5). Interestingly, the modest Dr
value obtained at room temperature improved toward the trans-
product evidently as the reaction temperature increased (entries
2
1
–4).
At this stage, the optimal conditions in Table 1 were set as
standards (conditions for entry 2 Table 1) for further studies. A
0
number of substituted isatins 3b–k were subjected to the stan- 11
dard conditions to test the substitution effects on isatin
aromatic ring (Table 2). These data demonstrated that the (trimethylsilyl)aryl triates 1 (1.2 equiv.), thioether 2a (1.5 equiv.), and
electronic property undoubtedly exerts profound effects on the
reactions, notably manifested by the yields of the corresponding
3k, 7-Cl
a
All reactions were performed on 0.25 mmol of isatins 3 with o-
ꢀ
b
CsF (3.0 equiv.) in anhydrous acetonitrile at 40 C overnight. Sum of
isolated yields of cis-4 and trans-4 aer column chromatography,
based on the isatin. Determined by the isolated yields of two isomers.
c
5
-subtituted spiroepoxy oxindoles 4, which roughly parallel with
the donating/withdrawing abilities of their 5-subtituents
entries 1–7). Strong electron donating 5-methoxyl group gave yield in comparison to its 5-epimer (entry 8 vs. 4), yet still less
(
4ac in a yield as low as 32%, while strong electron withdrawing than the parent isatin 3a (entry 1). The impressive electronic
5
-NO and 5-F groups delivered 4ag and 4af in 84% and 93% and positional effects, though lacking concrete rationale at this
2
yields respectively; isatins 3b, 3d and 3e bearing relatively time, may indicate that the epoxidation of isatin proceeded
weaker electron donating groups on 5-position resulted in stepwise with the rst step, namely, the nucleophilic attack of
moderate yields. 7-Cl isatin 3k under standard conditions ach-
ieved better yield (entry 11) than its 5- and 6-congeners (entries
5
and 9); and 4-Br isatin 3h showed a less negative impact on the
a
Table 3 The substrate scope of thioethers
a
Table 1 Optimization of reaction conditions
b
c
Entry Sulde 2, Ar, R
Product 4 yield (%) Dr (cis : trans)
1
2
3
4
5
6
7
8
9
2a, p-MePh, Z-PV
2b, p-MePh, 2-NO
2c, p-MePh, 2-ClPh
2d, p-MePh, 3-FPh
2e, p-MePh, 3-ClPh
2f, p-MePh, 4-ClPh
2g, p-MePh, CHCH2
2h, Ph, Ph
2i, Ph, Me
4af, 93
Ph 4bf, 99
4cf, 74
33 : 67d
31 : 69
57 : 43
74 : 26
81 : 19
70 : 30
46 : 56
61 : 39
47 : 53
2
d
ꢀ
b
c
Entry
1/2a/3a/CsF
T ( C)
Yield (%)
Dr (cis/trans)
4df, 89
4ef, 83
4ff, 92
4gf, 73
4hf, 83
4if, 85
1
2
3
4
5
1.2/1.5/1.0/3.0
1.2/1.5/1.0/3.0
1.2/1.5/1.0/3.0
1.2/1.5/1.0/3.0
1.0/1.0/1.6/3.0
25
40
60
80
40
68
87
65
41
56/44
44/56
35/65
21/79
27/73
d
68
a
All reactions were performed on 0.25 mmol of isatins 3a with o-
a
All reactions were performed on 0.25 mmol of N-methyl isatin 3a with (trimethylsilyl)aryl triates 1 (1.2 equiv.), thioether 2 (1.5 equiv.), and
ꢀ
b
o-(trimethylsilyl)aryl triate 1, thioether 2a, and CsF in anhydrous CsF (3.0 equiv.) in anhydrous acetonitrile at 40 C overnight. Sum of
b
acetonitrile. Sum of isolated yields of cis-4aa and trans-4aa aer isolated yields of cis-4 and trans-4 aer column chromatography,
c
c
d
column chromatography, based on the isatin. Determined by the based on the isatin. Estimated on the isolated yield. Determined
d
1
isolated yields of two isomers. Yield based on 1.
via the H NMR of the crude product. Z-PV ¼ Z-phenylvinyl.
7624 | RSC Adv., 2014, 4, 7623–7626
This journal is © The Royal Society of Chemistry 2014

View Article Online
Communication
RSC Advances
ylide on the isatin carbonyl group, as the rate limiting step.
Overall, this tandem reaction is fairly non-diastereoselective,
Acknowledgements
even though the steric effect at 4-position favours the cis-isomer We thank the Natural Science Foundation of China (21002032
more than the anti-isomer as exhibited by the highest cis/trans and 21272077), Shanghai Pujiang Program (11PJ1403100),
ratio of 76/24 presented in Table 2 entry 8 probably due to steric Priority Academic Program Development of Jiangsu Higher
effect.
Education Institutions (PAPD), and the Natural Science Foun-
With isatin 3f as epoxidation acceptor, a series of thioethers dation of Jiangsu Province (SBK201321632) for nancial
2
were examined under standard conditions, the results are support.
charted in Table 3 allylic, benzylic and simple alkyl aryl thio-
ethers all give good to excellent yields. As previously observed,
the diastereoselectivities are normally low and steric bulkiness
seems be an important factor which favours cis-isomers over
their trans-counterparts. More sterically demanding benzylic
thioethers 2c–f reversed the cis/trans ratio with an exception of
Notes and references
1 C. K. Ingold and J. A. Jessop, J. Chem. Soc., 1930, 713.
2 (a) A. W. Johnson and R. B. LaCount, J. Am. Chem. Soc., 1961,
83, 417; (b) E. J. Corey and M. Chaykovsky, J. Am. Chem. Soc.,
1962, 84, 3782; (c) E. J. Corey and M. Chaykovsky, J. Am.
Chem. Soc., 1965, 87, 1353; (d) B. M. Trost and
R. F. Hammen, J. Am. Chem. Soc., 1973, 95, 962; (e)
N. Furukawa, Y. Sugihara and H. Fujihara, J. Org. Chem.,
1989, 54, 4222; (f) A.-H. Li, L.-X. Dai, X.-L. Hou, Y.-Z. Huang
and F.-W. Li, J. Org. Chem., 1996, 61, 489; (g) A. Piccinini,
S. A. Kavanagh, P. B. Connon and S. J. Connon, Org. Lett.,
2010, 12, 608; (h) O. Illa, M. Namutebi, C. Saha, M. Ostovar,
C. C. Chen, M. F. Haddow, S. Nocquet-Thibault, M. Lusi,
E. M. McGarrigle and V. K. Aggarwal, J. Am. Chem. Soc., 2013,
135, 11951.
2
2-NO benzylic sulde 4bf whose strong dipolar nature may be
involved to some extent in the transition state.
The structure of these spiroepoxides has been established by
NMR spectra and high resolution mass spectra. Specically,
four pairs of representative diastereoisomers of 4af, 4ag, 4ff and
1
1
4
gf were each submitted to acquire 2D H– H NOESY spectrum.
The presence of cross-peaks at the 4-H next to the uoride atom
and the epoxide H set a key diagnosis interactions which
distinguished the cis-conguration from its anti-counterpart
without doubt (refer to the NOESY spectra in ESI†). The relative
stereochemistry of the others was assigned by analogy to those
four pairs.
3 (a) A.-H. Li, L.-X. Dai and X.-L. Hou, Chem. Commun., 1996,
491; (b) A.-H. Li, L.-X. Dai, X.-L. Hou and M.-B. Chen, J.
Org. Chem., 1996, 61, 4641; (c) V. K. Aggarwal,
A. Thompson, R. V. H. Jones and M. C. H. Standen, J. Org.
Chem., 1996, 61, 8368; (d) A.-H. Li, Y.-G. Zhou, L.-X. Dai,
X.-L. Hou, L.-J. Xia and L. Lin, Angew. Chem., Int. Ed., 1997,
36, 1317; (e) T. Saito, M. Sakairi and D. Akiba, Tetrahedron
Lett., 2001, 42, 5451; (f) V. K. Aggarwal, E. Alonso, G. Fang,
M. Ferrara, G. Hynd and M. Porcelloni, Angew. Chem., Int.
Ed., 2001, 40, 1433; (g) A. Solladi ´e -Cavallo, M. Roje,
ˇ
´
R. Welter and V. Sunjic, J. Org. Chem., 2004, 69, 1409.
4
(a) F. Krollpfeiffer and H. Hartmann, Chem. Ber., 1950, 83,
90; (b) E. J. Corey and M. Chaykovsky, J. Am. Chem. Soc.,
Fig. 2 Proposed mechanism for the cascade of benzyne formation,
sulfonium ylide formation and epoxidation.
1962, 84, 867; (c) S. Ye, Z.-Z. Huang, C.-A. Xia, Y. Tang and
L.-X. Dai, J. Am. Chem. Soc., 2002, 124, 2432; (d) L.-W. Ye,
X.-L. Sun, C.-Y. Zhu and Y. Tang, Org. Lett., 2006, 8, 3853;
(e) Y. Cheng, J. An, L.-Q. Lu, L. Luo, Z.-Y. Wang, J.-R. Chen
and W.-J. Xiao, J. Org. Chem., 2010, 76, 281; (f) S. L. Riches,
C. Saha, N. F. Filgueira, E. Grange, E. M. McGarrigle and
V. K. Aggarwal, J. Am. Chem. Soc., 2010, 132, 7626.
5 (a) J. E. Baldwin, R. E. Hackler and D. P. Kelly, J. Am. Chem.
Soc., 1968, 90, 4758; (b) J. E. Baldwin, R. E. Hackler and
D. P. Kelly, Chem. Commun., 1968, 537; (c) G. M. Blackburn,
W. D. Ollis, J. D. Plackett, C. Smith and I. O. Sutherland,
Chem. Commun., 1968, 186; (d) W. Kirmse and M. Kapps,
Chem. Ber., 1968, 101, 994; (e) R. W. C. Cose, A. M. Davies,
W. D. Ollis, C. Smith and I. O. Sutherland, J. Chem. Soc. D,
1969, 293; (f) E. Vedejs and J. P. Hagen, J. Am. Chem. Soc.,
1975, 97, 6878; (g) V. Cere, C. Paolucci, S. Pollicino,
E. Sandri and A. Fava, J. Org. Chem., 1978, 43, 4826; (h)
M. P. Doyle, J. H. Griffin, M. S. Chinn and D. Van Leusen,
J. Org. Chem., 1984, 49, 1917; (i) E. Vedejs, Acc. Chem. Res.,
A possible mechanism for this process has been outline in
Fig. 2. O-(trimethylsilyl)aryl triate 1 is converted to the reactive
benzyne 6, which is attacked by thioether 2 delivering inter-
mediate zwitterion 7. Immediate intramolecular 1,3-proton
shi from the alkyl carbon onto the aromatic carbon produces
sulfonium ylide 8. Reaction of 8 with isatin 3 gives the spi-
roepoxide 4 via intermediate 9.
Conclusions
In summary, we have established a one pot process to spiro
epoxyoxindoles. This method features two successive in situ
capturing steps of reactive intermediates in very mild condi-
tions. The use of o-(trimethylsilyl)aryl triate as benzyne source
upon a uoride activation is the base for this improved
protocol.
This journal is © The Royal Society of Chemistry 2014
RSC Adv., 2014, 4, 7623–7626 | 7625

View Article Online
RSC Advances
Communication
1
984, 17, 358; (j) E. Vedejs, J. D. Rodgers and
1996, 118, 7004; (g) Y. Zhang and J. Wang, Coord. Chem.
Rev., 2010, 254, 941.
S. J. Wittenberger, J. Am. Chem. Soc., 1988, 110, 4822; (k)
M. Ma, L. Peng, C. Li, X. Zhang and J. Wang, J. Am. Chem. 12 (a) G. M. Blackburn and W. D. Ollis, Chem. Commun., 1968,
Soc., 2005, 127, 15016; (l) D. Crich, Y. Zou and F. Brebion,
J. Org. Chem., 2006, 71, 9172; (m) S. Braverman and
M. Cherkinsky, Top. Curr. Chem., 2007, 275, 67.
(a) V. K. Aggarwal, H. Abdel-Rahman, R. V. H. Jones, H. Y. Lee
and B. D. Reid, J. Am. Chem. Soc., 1994, 116, 5973; (b)
V. K. Aggarwal, J. G. Ford, S. Fonquerna, H. Adams,
1261; (b) G. M. Blackburn, W. D. Ollis, C. Smith and
I. O. Sutherland, J. Chem. Soc. D, 1969, 99a.
13 (a) M. Hori, T. Kataoka, H. Shimizu and N. Ueda, Tetrahedron
Lett., 1981, 22, 3071; (b) J. Nakayama, A. Kimata,
H. Taniguchi and F. Takahashi, Bull. Chem. Soc. Jpn., 1996,
69, 2349.
6
R. V. H. Jones and R. Fieldhouse, J. Am. Chem. Soc., 1998, 14 (a) T. T. Jayanth, M. Jeganmohan, M.-J. Cheng, S.-Y. Chu and
20, 8328; (c) V. K. Aggarwal, E. Alonso, G. Hynd,
1
C.-H. Cheng, J. Am. Chem. Soc., 2006, 128, 2232; (b)
M. Jeganmohan, S. Bhuvaneswari and C.-H. Cheng, Angew.
Chem., Int. Ed., 2009, 48, 391; (c) G. Y. J. Im, S. M. Bronner,
A. E. Goetz, R. S. Paton, P. H. Y. Cheong, K. N. Houk and
N. K. Garg, J. Am. Chem. Soc., 2010, 132, 17933; (d)
X. Huang and T. Zhang, J. Org. Chem., 2010, 75, 506; (e)
R. V. Kolakowski and L. J. Williams, Nat. Chem., 2010, 2,
303; (f) K. Z. Laczkowski, D. Garcia, D. Pena, A. Cobas,
D. Perez and E. Guitian, Org. Lett., 2011, 13, 960; (g)
S. M. Bronner, J. L. Mackey, K. N. Houk and N. K. Garg, J.
Am. Chem. Soc., 2012, 134, 13966; (h) H. Yoshida,
S. Kawashima, Y. Takemoto, K. Okada, J. Ohshita and
K. Takaki, Angew. Chem., Int. Ed., 2012, 51, 235; (i)
A. V. Dubrovskiy and R. C. Larock, Tetrahedron, 2013, 69,
2789; (j) D. Rodriguez-Lojo, A. Cobas, D. Pena, D. Perez
and E. Guitian, Org. Lett., 2012, 14, 1363; (k) F. Sha, L. Wu
and X. Huang, J. Org. Chem., 2012, 77, 3754; (l) H. Ren,
C. Wu, X. Ding, X. Chen and F. Shi, Org. Biomol. Chem.,
2012, 10, 8975; (m) T. R. Hoye, B. Baire, D. Niu,
P. H. Willoughby and B. P. Woods, Nature, 2012, 490, 208;
(n) C. Hall, J. L. Henderson, G. Ernouf and M. F. Greaney,
Chem. Commun., 2013, 49, 7602; (o) D. Niu,
P. H. Willoughby, B. P. Woods, B. Baire and T. R. Hoye,
Nature, 2013, 501, 531; (p) B. Baire, D. Niu,
P. H. Willoughby, B. P. Woods and T. R. Hoye, Nat. Protoc.,
2013, 8, 501; (q) R. Karmakar, P. Mamidipalli, S. Y. Yun
and D. Lee, Org. Lett., 2013, 15, 1938; (r) S. Y. Yun,
K.-P. Wang, N.-K. Lee, P. Mamidipalli and D. Lee, J. Am.
Chem. Soc., 2013, 135, 4668; (s) K.-P. Wang, S. Y. Yun,
P. Mamidipalli and D. Lee, Chem. Sci., 2013, 4, 3205.
K. M. Lydon, M. J. Palmer, M. Porcelloni and J. R. Studley,
Angew. Chem., Int. Ed., 2001, 40, 1430; (d) V. K. Aggarwal
and C. L. Winn, Acc. Chem. Res., 2004, 37, 611.
(a) J.-C. Zheng, C.-Y. Zhu, X.-L. Sun, Y. Tang and L.-X. Dai, J.
Org. Chem., 2008, 73, 6909; (b) X.-L. Sun and Y. Tang, Acc.
Chem. Res., 2008, 41, 937; (c) B.-H. Zhu, J.-C. Zheng,
C.-B. Yu, X.-L. Sun, Y.-G. Zhou, Q. Shen and Y. Tang, Org.
Lett., 2009, 12, 504; (d) B.-H. Zhu, R. Zhou, J.-C. Zheng,
X.-M. Deng, X.-L. Sun, Q. Shen and Y. Tang, J. Org. Chem.,
7
8
2
010, 75, 3454.
(a) L.-Q. Lu, Y.-J. Cao, X.-P. Liu, J. An, C.-J. Yao, Z.-H. Ming
and W.-J. Xiao, J. Am. Chem. Soc., 2008, 130, 6946; (b)
L.-Q. Lu, Z.-H. Ming, J. An, C. Li, J.-R. Chen and W.-J. Xiao,
J. Org. Chem., 2011, 77, 1072; (c) L.-Q. Lu, J.-R. Chen and
W.-J. Xiao, Acc. Chem. Res., 2012, 45, 1278; (d) J. An,
L.-Q. Lu, Q.-Q. Yang, T. Wang and W.-J. Xiao, Org. Lett.,
2013, 15, 542; (e) Y. Cheng, X.-Q. Hu, S. Gao, L.-Q. Lu,
J.-R. Chen and W.-J. Xiao, Tetrahedron, 2013, 69, 3810.
(a) D. Michelot, G. Linstrumelle and S. Julia, J. Chem. Soc.,
Chem. Commun., 1974, 10; (b) E. Vedejs and G. R. Martinez,
J. Am. Chem. Soc., 1979, 101, 6452; (c) T. Cohen,
Z. Kosarych, K. Suzuki and L. C. Yu, J. Org. Chem., 1985,
9
50, 2965; (d) A. Padwa and J. R. Gasdaska, J. Org. Chem.,
1986, 51, 2857; (e) T. J. Chow, U.-K. Tan and S.-M. Peng,
Synth. Commun., 1988, 18, 519; (f) T. R. Hoye and
C. J. Dinsmore, Tetrahedron Lett., 1992, 33, 169; (g)
K. Hioki, S. Tani and Y. Sato, Synthesis, 1995, 649; (h)
A. Padwa, J. M. Kassir, M. A. Semones and
M. D. Weingarten, J. Org. Chem., 1995, 60, 53.
1
1
0 (a) B. M. Trost and L. S. Melvin, Sulfur ylides: emerging 15 (a) Y. Himeshima, T. Sonoda and H. Kobayashi, Chem. Lett.,
synthetic intermediates, Academic Press, 1975; (b)
J. S. Clark, Nitrogen, Oxygen, and Sulfur Ylide Chemistry: A
Practical Approach in Chemistry, Oxford University Press,
1983, 1211; (b) D. J. Atkinson, J. Sperry and M. A. Brimble,
Synthesis, 2010, 911; (c) S. M. Bronner and N. K. Garg, J.
Org. Chem., 2009, 74, 8842.
2
002.
1 (a) G. Andrews and D. A. Evans, Tetrahedron Lett., 1972, 13,
121; (b) W. Ando, S. Kondo, K. Nakayama, K. Ichibori,
16 (a) C. Palumbo, G. Mazzeo, A. Mazziotta, A. Gambacorta,
M. A. Loreto, A. Migliorini, S. Superchi, D. Tofani and
T. Gasperi, Org. Lett., 2011, 13, 6248; (b) M. S. Shmidt,
I. A. Perillo, M. Gonz ´a lez and M. M. Blanco, Tetrahedron
Lett., 2012, 53, 2514; (c) L. Hong and R. Wang, Adv. Synth.
Catal., 2013, 355, 1023.
5
H. Kohoda, H. Yamato, I. Imai, S. Nakaido and T. Migita, J.
Am. Chem. Soc., 1972, 94, 3870; (c) P. A. Grieco, D. Boxler
and K. Hiroi, J. Org. Chem., 1973, 38, 2572; (d) M. P. Doyle,
W. H. Tamblyn and V. Bagheri, J. Org. Chem., 1981, 46, 17 (a) P. Bravo, G. Gaudiano and A. Umani-Ronchi, Gazz. Chim.
5
1
094; (e) G. Shi, Y. Xu and M. Xu, Tetrahedron, 1991, 47,
629; (f) V. K. Aggarwal, J. G. Ford, A. Thompson,
Ital., 1970, 100, 652; (b) V. Schulz, M. Davoust, M. Lemarie,
J.-F. Lohier, S. J. S. De, P. Metzner and J.-F. Briere, Org.
Lett., 2007, 9, 1745.
R. V. H. Jones and M. C. H. Standen, J. Am. Chem. Soc.,
7626 | RSC Adv., 2014, 4, 7623–7626
This journal is © The Royal Society of Chemistry 2014