Peracetic acid mediated sp2 C-H selenation of arenes

Article abstract of DOI:10.1055/s-0035-1561408

Peracetic acid promoted C-Se coupling reaction of arenes with diselenides under metal-free and solvent-free conditions has been described. The resulting selenide ethers were obtained in good to excellent yields. Peracetic acid provided the selenide ethers

Full text of DOI:10.1055/s-0035-1561408

SYNLETT
0
9
3
6
-
5
2
1
4
1
4
3
7
-
2
0
9
6
© Georg Thieme Verlag Stuttgart · New York
2016, 27, A–F
letter
A
P.-A. Hsieh et al.
Letter
Synlett
Peracetic Acid Mediated sp2 C–H Selenation of Arenes
Ping-An Hsieha ◊
Satpal Singh Badsaraa,b ◊
Chia-Hsuan Tsaia
Daggula Mallikarjuna Reddya
Chin-Fa Lee*a
R1
R
R1
R2
R
AcOOH
R3SeSeR3
+
R3
Se
R2
120 °C, 24 h
R1
R1
R = Me, Et, OMe
1 = H, Me, Et
2 = H, Me
R3 = Ph, 2-ClC6H4,
4-ClC6H4, 2-F3CC6H4,
32–94% yield
18 examples
4-F3CC6H4, 2-BrC6H4,
4-BrC6H4
R
R
a Department of Chemistry, National Chung Hsing University,
Taichung, Taiwan 402, Taiwan
sp2 C–H functionalization
cfalee@dragon.nchu.edu.tw
b Current address: Department of Chemistry University of
Rajasthan, Jaipur 302004, Rajasthan, India
◊ Both authors contributed equally to this work.
Received: 29.11.2015
Accepted after revisison: 08.02.02016
Published online: 14.03.2016
Se
Me
Se
N
O
O
Me
CONH2
Me
HO
OH
N
NH
DOI: 10.1055/s-0035-1561408; Art ID: st-2015-w0925-l
O
OH
OH
Abstract Peracetic acid promoted C–Se coupling reaction of arenes
with diselenides under metal-free and solvent-free conditions has been
described. The resulting selenide ethers were obtained in good to ex-
cellent yields. Peracetic acid provided the selenide ethers via sp2 C–H
selenation whereas previously in case of DTBP sp3 C–H selenation was
observed.
N
H
cardiotonic agent
antitumor activity
HO
O
Key words peracetic acid, arenes, diselenides, C–Se coupling, sele-
nide ethers
HO
N
O
Se
2
HN
Organoselenium compounds have received renewed in-
terest due to their interesting applications in a variety of
immune and biological functions (Figure 1) such as preven-
tion of cardiovascular disease, antitumor, antiviral diseases,
as well as anti-aging effect, and the synthesis of these orga-
no selenium compounds is one of the emerging area in or-
ganic synthesis.1 The organoselenium compounds have
played an important role in cross-coupling reactions,2
asymmetric catalysis,3,4 organic synthesis,5–7 materials sci-
ence,8 and natural products.9 Moreover, the preparation of
peptides containing selenocysteine getting attention with
the discovery of an increasing number of proteins contain-
ing this amino acid.1f,10 Traditionally, photochemical or
harsh reaction conditions, such as the use of polar and toxic
solvents like HMPA and high reaction temperatures or ex-
pensive and toxic reagents have been used for the forma-
tion C–Se bond.11 Recently, several transition metals such as
palladium,12 nickel,13 copper,14 iron,15 indium,16 and zinc17
have been used as catalytic systems for the synthesis of or-
ganoselenium molecules.
O
OPRT inhibitor
Figure 1 Some biologically active organoselenium compounds
gard the peroxide chemistry have emerged as suitable sub-
stitute for traditional transition-metal catalysis.19 Tiecco
and co-workers20a demonstrated that the diselenides can be
conveniently employed to produce electrophilic 2-thie-
nylselenenylating agents which easily effect substitution
reactions on furan derivatives (Scheme 1, a). Kumar et al.20b
reported the synthesis of selenide ethers via K2S2O8-cata-
lyzed reaction between arenes and diselenides. Their meth-
odology required trifluoroacetic acid as strong acid for this
transformation (Scheme 1, b). Very recently, we have re-
ported a di-tert-butyl peroxide (DTBP) promoted syntheses
of selenide ethers and thioesters from methyl arenes via
metal-free sp3 C–H functionalization (Scheme 1, c).19a Now,
we have observed an interesting oxidant-dependent C–H
selenation of methyl arenes, and herein we report the per-
acetic acid (AcOOH) mediated sp2 C–H selenation of methyl
arenes under metal-free and solvent-free conditions
(Scheme 1, d).
Transition-metal-free C–H functionalization is an
emerging approach for constructing carbon–carbon and
carbon–heteroatom bonds in recent years18 and in this re-
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, A–F

B
P.-A. Hsieh et al.
Letter
Synlett
Tiecco's work (ref. 20a)
PhI(OAc)2
Se
Se
S
Me
(a)
Me
+
S
O
S
Se
Se
O
MeCN, r.t.
Kumar's work (ref. 20b)
SMe
K2S2O8, TFA
r.t.
Se
(b)
(c)
Se
+
SMe
our previous work (ref. 19a)
DTBP
Me
R1
Se
R
R
+
R1SeSeR1
R
120 °C, 24 h
sp3 C–H functionalization
this work
Me
Me
AcOOH
R1SeSeR1
+
R
(d)
R1
Se
120 °C, 24 h
sp2 C–H functionalization
Scheme 1 Metal-free synthesis of organoselenium compound
Our study began by selecting mesitylene (1a) as the
model and treated with diphenyl diselenide (2a) under the
influence of AcOOH at room temperature for 24 hours (Ta-
ble 1, entry 1); unfortunately no product was obtained in-
stead only starting materials were detected using GC–MS.
Enhancement in temperature (Table 1, entries 2–5) provid-
ed better results as 120 °C after 24 hours provided the cor-
responding selenide ether 3a in 94% yield (Table 1, entry 5).
Decrease in the reaction time diminished the product for-
mation (Table 1, entries 6–9). The spectroscopic analysis
(1H NMR and 13C NMR) of the product 3a were varied from
that of the earlier data (when the same reaction was carried
out using DTBP as oxidant).19 Then careful analysis of spec-
troscopic data confirm that the reaction underwent via sp2
C–H functionalization instead of sp3 C–H functionalization,
and the structure of compound 3a was then established as
shown in Table 1.
Once we have optimized conditions in our hand, we
then turned our attention towards generalization of this in-
teresting sp2 C–H selenation strategy. In this regard, we
have carried out the reaction of mesitylene (1a) with a vari-
ety of diaryl diselenides using AcOOH under optimized re-
action conditions (Table 2, entries 1–6). The resultant sele-
nide ethers 3b–g were obtained in good to excellent yields.
Different methyl arenes 1b–d were also employed for this
C–H selenation with various diselenides under the same re-
action conditions and afforded the resulting selenide ethers
in good yields (Table 2, entries 7–15). Not only methyl
arenes but also ethyl arenes were tested in this reaction,
Table 1 Optimization of Reaction Conditionsa
Me
Me
Se
Me
Me
+
AcOOH
PhSeSePh
Ph
2a
Me
Me
3a
1a
Entry
Temp (°C)
Time (h)
Yield (%)b
1
2
r.t.
60
24
24
24
24
24
12
6
n.r.
11
15
91
94
88
24
22
12
91c
3
80
4
100
120
120
120
120
120
120
5
6
7
8
3
9
1
10
24
a Reaction conditions: mesitylene (1a, 1.0 mL), diphenyl diselenide (2a, 0.5
mmol), AcOOH (1.0 mmol).
b Isolated yield.
c 4 Å MS was used.
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, A–F

C
P.-A. Hsieh et al.
Letter
Synlett
and we could obtain the selenide ethers via sp2 C–H selena-
tion only (Table 2, entries 16 and 17). The system shows
good functional-group tolerance as chloro, bromo, trifluo-
romethyl, and methoxy groups were all tolerated by the re-
action conditions employed.
phenyl diselenide (2a) will react with AcOOH to form
PhSeOH and phenylselenylacetate as transient species. Phe-
nylselenylacetate and PhSeOH undergo electrophilic substi-
tution with mesitylene to afford mesityl(phenyl)selane
(3a).
The plausible mechanism of this reaction can be depict-
ed by choosing mesitylene (1a) and diphenyl diselenide
(2a) as reacting partners as shown in Scheme 2. Initially, di-
Table 2 Reactions of Various Alkyl Arenes 1 with Diaryldiselenides 2a
R1
R1
AcOOH
R3SeSeR3
+
R2
R2
R3
120 °C, 24 h
Se
1
2
3
Entry
1
1
R3
Product
Yield (%)b
Me
Me
Me
Se
4-F3CC6H4
4-BrC6H4
4-ClC6H4
2-ClC6H4
4-BrC6H4
2-F3CC6H4
Ph
40
Me
3b
Me
CF3
Me
Me
1a
Se
2
3
4
5
6
7
1a
1a
1a
1a
1a
81
88
79
73
59
65
Me
3c
Me
Br
Cl
Me
Me
Me
Me
Me
Se
Me
3d
Me
Cl
Se
Me
3e
Me
Br
Se
Me
3f
Me
CF3
Se
Me
3g
Me
Me
Se
Me
1b
Me
3h
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, A–F

D
P.-A. Hsieh et al.
Letter
Synlett
Table 2 (continued)
Entry
1
R3
Product
Yield (%)b
Me
Me
Se
Se
8
1b
1b
4-ClC6H4
60
63
Cl
Br
Me
3i
9
4-BrC6H4
Me
3j
OMe
OMe
Me
Se
Se
10
Ph
67
75
89
Me
1c
1c
3k
OMe
11
12
4-ClC6H4
Cl
Br
Me
3l
OMe
Se
1c
4-BrC6H4
Me
3m
OMe
OMe
OMe
Se
Se
Se
13
14
15
16
17
Ph
54
72
88
40
32
Me
Me
3n
1d
1d
1d
4-ClC6H4
4-BrC6H4
Ph
Cl
Br
Me
3o
OMe
Me
3p
Et
Et
Se
Et
Et
1e
Et
Et
3q
Et
Se
Et
1e
4-ClC6H4
Et
3r
Cl
a Reaction conditions: various methyl arenes (1.0 mL), diaryl diselenide (0.5 mmol), AcOOH (1.0 mmol), 120 °C, 24 h.
b Isolated yield.
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, A–F

E
P.-A. Hsieh et al.
Letter
Synlett
References and Notes
Se
Se
(1) (a) Shamberger, R. J. In Biochemistry of Selenium; Plenum Press:
New York, 1983. (b) Klayman, D. L.; Gunter, H. H. In Organosele-
nium Compounds: Their Chemistry and Biology: Wiley-Inter-
science: New York, 1973;. (c) Rotruck, J. T.; Pope, A. L.; Ganther,
H. E.; Swanson, A. B.; Hafeman, D. G.; Hoekstra, W. G. Science
1973, 179, 588. (d) Flohe, L.; Gunzler, E. A.; Schock, H. H. FEBS
Lett. 1973, 32, 132. (e) Flohe, L.; Andreesen, J. R.; Brigelius-
Flohe, R.; Maiorino, M.; Ursini, F. IUBMB Life 2000, 49, 411.
(f) Jacob, C.; Giles, G. I.; Giles, N. M.; Sies, H. Angew. Chem. Int. Ed.
2003, 42, 4742. (g) Sarma, B. K.; Mugesh, G. Org. Biomol. Chem.
2008, 6, 965. (h) Nogueira, C. W.; Zeni, G.; Rocha, J. B. T. Chem.
Rev. 2004, 104, 6255. (i) Mugesh, G.; du Mont, W. W.; Sies, H.
Chem. Rev. 2001, 101, 2125. (j) Mugesh, G.; Singh, H. Chem. Soc.
Rev. 2000, 29, 347. (k) Patani, G. A.; LaVoie, E. J. Chem. Rev. 1996,
96, 3147. (l) Abdo, M.; Zhang, Y.; Schramm, V. L.; Knapp, S. Org.
Lett. 2010, 12, 2982.
O
2a
O
Me
O
H
Se
OH
Me
Me
O
Se
Me
O
Me
1a
H2O
O
Se
OH
Me
O
(2) (a) Braga, A. L.; Barcellos, T.; Paixao, M. W.; Deobald, A. M.;
Godoi, M.; Stefani, H. A.; Cella, R.; Sharma, A. Organometallics
2008, 27, 4009. (b) Perin, G.; Lenardao, E. J.; Jacob, R. G.;
Panatieri, R. B. Chem. Rev. 2009, 109, 1277.
Se
H
O
Me
Me
+
(3) (a) Fukuzawa, S.-i.; Tsudsuki, K. Tetrahedron: Asymmetry 1995,
6, 1039. (b) Wirth, T. Tetrahedron Lett. 1995, 36, 7849. (c) Braga,
A. L.; Vargas, F.; Sehnem, J. A.; Braga, R. C. J. Org. Chem. 2005, 70,
9021. (d) Zielinska-Blajet, M.; Siedlecka, R.; Skarzewski, J. Tetra-
hedron: Asymmetry 2007, 18, 131. (e) Schwab, R. S.; Soares, L. C.;
Dornelles, L.; Rodrigues, O. E. D.; Paixao, M. W.; Godoi, M.;
Braga, A. L. Eur. J. Org. Chem. 2010, 3574. (f) Vargas, F.; Sehnem,
J. A.; Galetto, F. Z.; Braga, A. L. Tetrahedron 2008, 64, 392.
(g) Wirth, T.; Kulicke, K. J.; Fragale, G. Helv. Chim. Acta 1996, 79,
1957. (h) Wojaczynska, E.; Skazewski, J. Tetrahedron: Asymme-
try 2008, 19, 593.
O
Me
O
Me
OH
Me
Se
Me
CH3
(4) For reviews, see: (a) Wirth, T. Tetrahedron 1999, 55, 1. (b) Wirth,
T. Angew. Chem. Int. Ed. 2000, 39, 3740. (c) Braga, A. L.; Ludtke,
D. S.; Vargas, F.; Braga, R. C. Synlett 2006, 1453. (d) Braga, A. L.;
Ludtke, D. S.; Vargas, F.; Braga, R. C. Curr. Org. Chem. 2006, 10,
1921. (e) Godoi, M.; Paixao, M. W.; Braga, A. L. Dalton Trans.
2011, 40, 11347.
3a
Me
Scheme 2 Plausible mechanism
(5) (a) Freudendahl, D. M.; Iwaoka, M.; Wirth, T. Eur. J. Org. Chem.
2010, 3934. (b) Zhao, L.; Li, Z.; Wirth, T. Eur. J. Org. Chem. 2011,
176. (c) Shahzad, S. A.; Vivant, C.; Wirth, T. Org. Lett. 2010, 12,
1364. (d) Braga, A. L.; Zeni, G.; Andrade, L. H.; Silveira, C. C.
Synlett 1997, 595. (e) Browne, D. M.; Niyomura, O.; Wirth, T.
Org. Lett. 2007, 9, 3169. (f) Tiecco, M.; Testaferri, L.; Tingoli, M.;
Bagnoli, L.; Santi, C. Synlett 1993, 798.
(6) (a) Wirth, T. Topics in Current Chemistry in Organoselenium
Chemistry; Springer: Heidelberg, 2000, 208. (b) Krief, A. In Com-
prehensive Organometallic Chemistry II; Vol. 11; Abel, E. V.;
Stone, F. G. A.; Wilkinson, G., Eds.; Chap. 13; Pergamon Press:
New York, 1995, 515. (c) Paulmier, C. In Selenium Reagents and
Intermediates in Organic Synthesis, Organic Chemistry Series 4;
Baldwin, J. E., Ed.; Pergamon Press: Oxford, 1986.
(7) (a) Keck, G. E.; Grier, M. C. Synlett 1999, 1657. (b) Chen, C.;
Crich, D.; Papadatos, A. J. Am. Chem. Soc. 1992, 114, 8313.
(c) Boger, D. L.; Mathvink, R. J. J. Org. Chem. 1992, 57, 1429.
(d) Hiiro, T.; Morita, Y.; Inoue, T.; Kambe, N.; Ogawa, A.; Ryuand,
I.; Sonoda, N. J. Am. Chem. Soc. 1990, 112, 455. (e) Sviridov, A. F.;
Erolenko, M. S.; Yashunky, D. V.; Kochetkov, N. K. Tetrahedron
Lett. 1983, 24, 4355.
(8) (a) Heppke, G.; Martens, J.; Praefcke, K.; Simon, H. Angew. Chem.,
Int. Ed. Engl. 1977, 16, 318. (b) Yamada, J.-i.; Akutsu, H.;
Nishikawa, H.; Kikuchi, K. Chem. Rev. 2004, 104, 5057.
In conclusion, we have developed an interesting transi-
tion-metal-free peracetic acid promoted C–Se coupling re-
action of arenes with diselenides under solvent-free condi-
tions,21 and the resulting selenide ethers were obtained in
good to excellent yields. Peracetic acid provided the sele-
nide ethers via sp2 C–H selenation. The system shows good
functional-group tolerance.
Acknowledgment
The National Science Council, Taiwan (NSC 104-2113-M-005-002)
and National Chung Hsing University are gratefully acknowledged for
financial support. C.F.L. is a Golden-Jade Fellow of Kenda Foundation,
Taiwan.
Supporting Information
Supporting information for this article is available online at
http://dx.doi.org/10.1055/s-0035-1561408.
S
u
p
p
ortiInfogrmoaitn
S
u
p
p
ortioInfgrmoaitn
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, A–F

F
P.-A. Hsieh et al.
Letter
Synlett
(9) (a) Inoue, M.; Yamahita, S.; Ishihara, Y.; Hirama, M. Org. Lett.
2006, 8, 5805. (b) Martin, S. F.; Chen, K. X.; Eary, C. T. Org. Lett.
1999, 1, 79.
(10) (a) Stadman, T. C. Annu. Rev. Biochem. 1996, 65, 83.
(b) Muttenthaler, M.; Alewood, P. F. J. Pept. Chem. 2008, 14,
1223.
(11) (a) Testaferri, L.; Tiecco, M.; Tingoli, M.; Chianelli, D.;
Montanucci, M. Synthesis 1983, 751. (b) Suzuki, H.; Abe, H.;
Suka, V. Chem. Lett. 1981, 151. (c) Pierini, A. B.; Rossi, R. A. J. Org.
Chem. 1979, 44, 4667. (d) Rossi, R. A.; Penenory, A. B. J. Org.
Chem. 1981, 46, 4580. (e) Grieco, P. A.; Gilman, S.; Nishizawa, M.
J. Org. Chem. 1976, 41, 1458.
(12) (a) Itoh, T.; Mase, T. Org. Lett. 2004, 6, 4587. (b) Murata, M.;
Buchwald, S. L. Tetrahedron 2004, 60, 7397. (c) Mispelaere-
Canivet, C.; Spindler, J. F.; Perrio, S.; Beslin, P. Tetrahedron 2005,
61, 5253. (d) Fernandez-Rodriguez, M. A.; Shen, Q. L.; Hartwig, J.
F. J. Am. Chem. Soc. 2006, 128, 2180.
(17) (a) Bieber, L. W.; de Sa, A. C. P. F.; Menezes, P. H.; Goncalves, S.
M. C. Tetrahedron Lett. 2001, 42, 4597. (b) Narayanaperumal, S.;
Alberto, E. E.; Gul, K.; Kawasoko, C. Y.; Dornelles, L.; Rodrigues,
O. E. D.; Braga, A. L. Tetrahedron 2011, 67, 4723.
(18) (a) Charushin, V. S.; Chupakhin, O. N. In Metal-Free C–H Func-
tionalization of Aromatic Compounds through the Action of Nuc-
leophilic Reagents; Springer: New York, 2014. (b) Sun, C.-L.; Shi,
Z.-J. Chem. Rev. 2014, 114, 9219. (c) Wang, D.; Ge, B.; Li, L.; Shan,
J.; Ding, Y. J. Org. Chem. 2014, 79, 8607. (d) Li, L.; Zhao, Y.-L.;
Wang, Q.; Lin, T.; Liu, Q. Org. Lett. 2015, 17, 370.
(19) (a) Badsara, S. S.; Liu, Y.-C.; Hsieh, P.-A.; Zeng, J.-W.; Lu, S.-Y.;
Liu, Y.-W.; Lee, C.-F. Chem. Commun. 2014, 50, 11374. (b) Du, B.;
Jin, B.; Sun, P. Org. Lett. 2014, 16, 3032. (c) Yuan, J.; Ma, X.; Yi,
H.; Liu, C.; Lei, A. Chem. Commun. 2014, 50, 14386. (d) Xue, Q.;
Xie, J.; Li, H.; Cheng, Y.; Zhu, C. Chem. Commun. 2013, 49, 3700.
(e) Liou, J.-C.; Badsara, S. S.; Huang, Y.-T.; Lee, C.-F. RSC Adv.
2014, 4, 41237. (f) Zeng, J.-W.; Liu, Y.-C.; Hsieh, P.-A.; Huang, Y.-
T.; Yi, C.-L.; Badsara, S. S.; Lee, C.-F. Green Chem. 2014, 16, 2644.
(g) Liu, D.; Lei, A. Chem. Asian J. 2015, 10, 806.
(20) (a) Teicco, M.; Testaferri, L.; Bagnoli, L.; Marini, F.; Temperini, A.;
Tomassini, C.; Santi, C. Tetrahedron 2000, 56, 3255. (b) Prasad, C.
D.; Balkrishna, S. J.; Kumar, A.; Bhakuni, B. S.; Shrimali, K.;
Biswas, S.; Kumar, S. J. Org. Chem. 2013, 78, 1434.
(13) (a) Cristau, H. J.; Chabaud, B.; Labaudiniere, R.; Christol, H.
Organometallics 1985, 4, 657. (b) Percec, V.; Bae, J. Y.; Hill, D. H.
J. Org. Chem. 1995, 60, 6895.
(14) (a) Beletskaya, I. P.; Sigeev, A. S.; Peregudov, A. S.; Petrovskii, P.
V. Tetrahedron Lett. 2003, 44, 7039. (b) Gujadhur, R. K.;
Venkataraman, D. Tetrahedron Lett. 2003, 44, 81. (c) Taniguchi,
N.; Onami, T. J. Org. Chem. 2004, 69, 915. (d) Kumar, S.; Engman,
L. J. Org. Chem. 2006, 71, 5400. (e) Alves, D.; Santos, C. G.; Paixao,
M. W.; Soares, L. C.; de Souza, D.; Rodrigues, O. E. D.; Braga, A. L.
Tetrahedron Lett. 2009, 50, 6635. (f) Saha, A.; Saha, D.; Ranu, B.
C. Org. Biomol. Chem. 2009, 7, 1652. (g) Singh, D.; Alberto, E. E.;
Rodrigues, O. E. D.; Braga, A. L. Green Chem. 2009, 11, 1521.
(h) Bhadra, S.; Saha, A.; Ranu, B. C. J. Org. Chem. 2010, 75, 4864.
(15) (a) Correa, A.; Carril, M.; Bolm, C. Angew. Chem. Int. Ed. 2008, 47,
2880. (b) Wu, W. Y.; Wang, J. C.; Tsai, F. Y. Green Chem. 2009, 11,
326. (c) Wang, M.; Ren, K.; Wang, L. Adv. Synth. Catal. 2009, 351,
1586. (d) Lee, C.-F.; Wu, J. R.; Lin, C. H. Chem. Commun. 2009,
4450.
(21) General Procedure for
a Representative Example: Mesi-
tyl(phenyl)selane (3a)
A Schlenk tube equipped with a magnetic stir bar was charged
with diphenyl diselenide (0.5 mmol, 0.157 g), mesitylene (1.0
mL), and AcOOH (1.0 mmol), then heated at 120 °C in an oil bath
under N2 atmosphere. After stirring at this temperature for 24 h,
the reaction mixture was cooled to r.t. and diluted with EtOAc
(20 mL). The resulting solution was directly filtered through a
pad of Celite then washed with EtOAc (20 mL) and concentrated
to give the crude material which was then purified by column
chromatography (SiO2, hexane) to provide 3a as a yellow oil
(248 mg, 94% yield). 1H NMR (400 MHz, CDCl3): δ = 2.30 (s, 3 H),
2.43 (s, 6 H), 6.99 (s, 2 H), 7.06–7.13 (m, 5 H) ppm. 13C NMR
(100 MHz, CDCl3): δ = 21.0, 24.2, 125.3, 128.4, 128.8, 128.9,
129.1, 133.4, 139.0, 143.6 ppm. 77Se NMR (114.45 MHz, CDCl3):
δ = 286.3 ppm. HRMS (EI): m/z calcd for C15H16Se: 276.0417;
found: 276.0407.
(16) (a) Narayanaperumal, S.; Alberto, E. E.; de Andrade, F. M.;
Lenardao, E. J.; Taube, P. S.; Braga, A. L. Org. Biomol. Chem. 2009,
7, 4647. (b) Wang, L.; Ren, K.; Wang, M. Org. Biomol. Chem. 2009,
7, 4858.
© Georg Thieme Verlag Stuttgart · New York — Synlett 2016, 27, A–F