A tandem intramolecular Michael addition/Wittig reaction for the synthesis of fused cyclohexadiene derivatives

Article abstract of DOI:10.1002/cjoc.201090274

A tandem intramolecular Michael addition/Wittig reaction has been developed for the synthesis of fused cyclohexadiene derivatives from phosphonium salt 3. This annulation reaction affords the cyclohexadienes in moderate to excellent yields, depending on t

Full text of DOI:10.1002/cjoc.201090274

FULL PAPER
A Tandem Intramolecular Michael Addition/Wittig Reaction for
the Synthesis of Fused Cyclohexadiene Derivatives†
Wang, Qinggang(王庆刚)
Zheng, Juncheng(郑君成)
Sun, Xiuli(孙秀丽)
Tang, Yong*(唐勇)
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry,
Shanghai 200032, China
A tandem intramolecular Michael addition/Wittig reaction has been developed for the synthesis of fused cyclo-
hexadiene derivatives from phosphonium salt 3. This annulation reaction affords the cyclohexadienes in moderate
to excellent yields, depending on the substrates. A mechanism is proposed to account for the tandem process.
Keywords tandem intramolecular reaction, Michael addition, Wittig reaction, fused cyclohexadiene derivative,
mechanism
Introduction
paper, we wish to report this reaction in details.
Ylide reactions have been developed as a very pow-
erful method to construct carbon-carbon double bonds
and carbon-heteroatom bonds since Wittig reaction was
reported in 1950 s.1 In the past decades, much attention
has been paid to the construction of three-membered
ring compounds, especially to epoxides,2 cyclopro-
panes2a,2c,2d,3 and aziridines,2a,2c,2d,4 which occurs fre-
quently in biologically active compounds as well as
their utility as valuable synthetic intermediates. Re-
cently, lots of effort has been concentrated on con-
structing cyclic compounds beyond three-membered
rings via ylide routes,5 such as dihydrofuran,6 dihydro-
pyrroles,7 and isoxazoline N-oxide derivatives8 etc. Be-
sides, taking advantage of the tandem or cascade reac-
tions via ylide to form multicylic rings compounds in
one pot has also gained increasing attention.9
Scheme 1 Intramolecular Michael addition/ylide epoxidation
for the synthesis of cyclohexadiene epoxides
Scheme 2 Intramolecular Michael addition/Wittig reaction for
the synthesis of cyclohexadiene derivatives
Allylic phosphorus ylides have been employed for
the construction of cyclohexadiene derivatives via in-
termolecular ylide-initiated Michael addition/olefination
reaction.10 In our previous studies on ylide chemistry,
we reported a tandem intramolecular Michael addi-
tion/ylide epoxidation reaction of allylic sulfur salts 1
for the synthesis of the highly functionalized fused
cyclohexadiene epoxides 2 with three stereocenters
(Scheme 1).9c Recently, we developed an intramolecular
Michael addition/Wittig reaction for the synthesis of
fused cyclohexadiene derivatives 4 when sulfur salts 1
are replaced with the corresponding phosphonium salts
3 (Scheme 2), which are very important subunits in a
number of biologically active compounds as well as
versatile intermediates in organic synthesis.11 In this
Results and discussion
The synthesis of substrates 3 is shown in Scheme 3.
Phosphonium salts 3 were obtained from the corre-
sponding bromide compounds 5, by treating with
triphenylphosphine in toluene, followed by washing
with ether, drying in vacuo, which were used directly
without any further purification (Scheme 3).
*
E-mail: tangy@mail.sioc.ac.cn; Tel.: 0086-021-54925156
Received June 25, 2010; revised July 26, 2010; accepted August 10, 2010.
Project supported by the National Natural Science Foundation of China (Nos. 20821002, 20932008), the Major State Basic Research Development Program
(No. 2009CB825300).
† Dedicated to the 60th Anniversary of Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences.
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Chin. J. Chem. 2010, 28, 1618— 1622

A Tandem Intramolecular Michael Addition/Wittig Reaction
Scheme 3 Synthesis of the phosphonium salts 3
(Entry 9, Table 2), probably because of the unfavorable
constrained transition state involving seven-membered
ring system. Elevated temperature was necessary when
n was 1, furnishing the desired fused cyclohexadiene 4a
in 55% yield (Entry 1, Table 2). The substituents of ke-
tone moiety also affected the yield of this reaction. For
instance, 3b containing phenyl group (R＝Ph) gave the
cyclohexadiene 4b in 95% yield (Entry 2, Table 2).
Substrates bearing electron-withdrawing substituents on
the phenyl group (R ＝ C6H4-p-Cl, C6H4-p-Br) also
worked very well, giving the desired products in 92%
and 87% yields respectively (Entries 3 and 4, Table 2).
However, an introduction of electron-donating substitu-
ent on the phenyl group (R＝C6H4-p-Me, C6H4-p-OMe)
decreased yields obviously (Entries 5 and 6, Table 2).
We next tried the reaction of aliphatic substrate 3g and
found that the desired tandem process occurred
smoothly, affording cyclohexadiene 4g in 62% yield
(Entry 7, Table 2). α,β-Unsaturated aldehyde 3h was
also suitable for this tandem process and 51% yield was
achieved (Entry 8, Table 2).
The present tandem reaction could be accounted by
the proposed mechanism as shown in Scheme 4. This
reaction is initiated by intramolecular Michael addition of
α,β-unsaturated ketone with ylide 3-A, generated in situ
from the corresponding phosphonium salt under basic
conditions, to form intermediates 3-B. Subsequent proton
migration leads to phosphonium ylide 3-C, followed by
an intramolecular Wittig reaction affording the desired
fused cyclohexadiene derivatives 4 via intermediate
3-INT. In 3-INT, both the oxygen anion and the phos-
phonium cation are located at cis position, favoring the
syn-elimination of triphenyl phosphine oxide. A detailed
mechanism waits for further investigation.
With phosphonium salts 3 at hands, we firstly treated
3b with K2CO3 in THF at 25 ℃ for 18 h. We were
pleased to find that the desired product 4b was isolated
in 29% yield. To improve the yields, the reaction condi-
tions were further optimized. As shown in Table 1, the
reaction conditions influenced the yield greatly. The
yield was only 29% at room temperature (Entry 1, Table
1), elevating the temperature increased the yield to 80%
and 95% respectively (Entries 2 and 3, Table 1). The
yield is also base-dependent. Compared with K2CO3,
Na2CO3 was a good base for the reaction (Entry 4, Table
1). But both Cs2CO3 and t-BuOK decreased the yield
obviously (Entries 5 and 6, Table 1). Although this tan-
dem Michael addition/Wittig reaction could proceed in
several solvents, THF was still the optimal (Entries 7—
10, Table 1).
Table 1 Influence of reaction conditions on the intramolecular
tandem reactiona
Entry
Solvent
THF
Base
t/℃
25
50
60
60
60
60
60
60
60
60
Yieldb/%
29
Experimental section
1
2
K2CO3
K2CO3
K2CO3
Na2CO3
Cs2CO3
t-BuOK
K2CO3
K2CO3
K2CO3
K2CO3
All reactions were carried out under N2 unless oth-
erwise noted. All solvents were purified according to
THF
80
3
THF
95
standard methods prior to use. H NMR and 13C NMR
1
4
THF
87
spectra were recorded in chloroform-d3 on a VARIAN
Mercury 300 M. All IR (Perkin-Elmer 983 or BioRad
FTS-185), MSLR and MSHR (HP5989A and Premier
CAB088) data were obtained by the analytical center of
Shanghai Institute of Organic Chemistry.
5
THF
57
6
THF
41
7
CH3CN
DCE
46
8
49
9
Dioxane
81
General procedure for synthesis of phosphonium
salts 3 (3a as an example)
10
Toluene
51
a Salts (0.2 mmol), base (0.3 mmol), solvent 3 mL, 25—60 ℃, 18
A mixture of crotonate-derived bromides 5a (0.618 g,
2.0 mmol) and 1.1 equiv. of triphenylphosphine (0.576 g,
2.2 mmol) in toluene (2 mL) was stirred for 24 h. The
white phosphonium salt was collected, washed with ether,
and dried under reduced pressure to give 1.2 g of the
crude phosphonium salts 3a in quantitative yield, which
was used directly without further purification.
h; b Isolated yield.
The generality of this reaction was investigated un-
der the optimal reaction conditions. As shown in Table 2,
this tandem reaction proves to be strongly influenced by
the substrate structures and the fused cyclohexadienes
were afforded in moderate to excellent yields. For ex-
ample, the tandem reaction proceeded very well when n
was 2 (Entries 1—8, Table 2). However, increasing n
from 2 to 3, the annulation reaction did not work at all
General procedure of the tandem intramolecular
reaction (3a as an example)
To a stirred mixture of phosphonium salt 3a (0.114
Chin. J. Chem. 2010, 28, 1618— 1622
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Wang et al.
FULL PAPER
Table 2 Scope of the tandem intramolecular Michael addition/Wittig reactiona
Entry
1b
Substrate
n
R
Product
Yieldc/%
55
3a
3b
3c
3d
3e
3f
1
Ph
2
3
2
2
2
2
2
2
2
3
Ph
p-ClC6H4
p-BrC6H4
p-MeC6H4
p-MeOC6H4
Me
95
92
4
87
5
79
6b
49
7
3g
3h
3i
62
8
H
51
9b
Ph
trace
a Salts (0.2 mmol), K2CO3 (0.3 mmol) as base, THF as solvent, 60 ℃, 18 h; b Toluene as solvent, 100 ℃; c Isolated yield.
Scheme 4 A proposed mechanism of the tandem reaction
g, 0.2 mmol) in dry THF (2.5 mL) was added K2CO3
tion was complete, the reaction mixture was passed
through a glass funnel with a thin layer of silica gel, and
(0.042 g, 0.3 mmol) at 60 ℃ for 18 h. After the reac-
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Chin. J. Chem. 2010, 28, 1618— 1622

A Tandem Intramolecular Michael Addition/Wittig Reaction
eluted with ethyl acetate. The filtrate was concentrated
and the residue was purified by a flash column chroma-
tography to afford the fused cyclohexadiene 4a as a
white solid. Yield 0.024 g (55%).
2.95—2.75 (m, 2H), 2.50—2.42 (m, 1H), 2.37 (s, 3H),
2.14—2.07 (m, 1H), 1.99—1.85 (m, 1H); 13C NMR
(CDCl3, 75 MHz) δ: 165.4, 144.9, 138.8, 137.1, 136.1,
129.3, 125.3, 123.4, 119.9, 67.6, 32.87, 32.84, 29.2,
21.1; IR (KBr) ν: 1688 (s), 1543 (m), 1268 (m), 810 (m),
＋
－1
Characterization data of all new synthesized com-
pounds 4a— 4h
747 (w) cm ; MS (EI) m/＋z (%): 240 (M , 100); HRMS
(EI) calcd for C16H16O2 (M ) 240.1150, found 240.1145.
6-(4-Methoxyphenyl)-3,4,4a,5-tetrahydroisochrom-
en-1-one (4f) White solid, 49% yield. 1H NMR
(CDCl3, 300 MHz) δ: 7.49—7.42 (m, 3H), 6.93—6.89
(m, 2H), 6.51—6.48 (m, 1H), 4.52—4.48 (m, 1H), 4.30
(t, J＝11.7 Hz, 1H), 3.84 (s, 3H), 2.97—2.78 (m, 2H),
2.48—2.35 (m, 1H), 2.14—2.07 (m, 1H), 1.99—1.86 (m,
1H); 13C NMR (CDCl3, 75 MHz) δ: 165.5, 160.0, 144.6,
137.3, 131.3, 126.8, 122.8, 119.0, 113.9, 67.6, 55.3,
32.89, 32.84, 29.3; IR (KBr) ν: 1685 (s), 1544 (m), 1270
5-Phenyl-3a,4-dihydroisobenzofuran-1(3H)-one (4a)
1
White solid, 55% yield. H NMR (CDCl3, 300 MHz) δ:
7.50 (d, J＝6.6 Hz, 2H), 7.42—7.34 (m, 3H), 7.11—
7.08 (m, 1H), 6.64—6.61 (m, 1H), 4.77 (t, J＝8.7 Hz,
1H), 4.01 (t, J＝8.7 Hz, 2H), 3.36—3.21 (m, 1H), 2.98
(dd, J＝16.2, 8.7 Hz, 1H), 2.59—2.46 (m, 1H); 13C
NMR (CDCl3, 75 MHz) δ: 169.4, 142.7, 139.2, 130.2,
128.7, 128.6, 125.6, 124.7, 121.4, 72.7, 33.8, 30.5; IR
(KBr) ν: 1752 (s)－, 1662 (w), 1550 (m), 1225 (m), 1038
＋
1
＋
－1
(m), 734 (m) cm ; MS (EI) m/z (%): 212 (M , 100);
HRMS (EI) calcd for C14H12O2 (M＋) 212.0837, found
212.0833.
(w), 814 (w), 748 (w) cm ; MS (EI) m/z (%): 256 (M ,
100); HRMS (EI) calcd for C16H16O3 (M＋) 256.1099,
found 256.1098.
6-Phenyl-3,4,4a,5-tetrahydroisochromen-1-one (4b)
White solid, 95% yield. H NMR (CDCl3, 300 MHz) δ:
6-Methyl-3,4,4a,5-tetrahydroisochromen-1-one (4g)
White solid, 62% yield. H NMR (CDCl3, 300 MHz) δ:
1
1
7.51—7.48 (m, 2H), 7.41—7.32 (m, 4H), 6.56—6.53 (m,
1H), 4.51—4.47 (m, 1H), 4.29 (t, J＝11.4 Hz, 1H),
2.96—2.76 (m, 2H), 2.51—2.39 (m, 1H), 2.12—2.07 (m,
1H), 1.98—1.85 (m, 1H); 13C NMR (CDCl3, 75 MHz) δ:
165.3, 144.9, 138.9, 136.8, 128.6, 128.5, 125.3, 123.8,
120.7, 67.6, 32.8, 32.7, 29.1; IR (KB－r) ν: 1687 (s), 1543
7.26—7.23 (m, 1H), 5.95—5.92 (brs, 1H), 4.48—4.42
(m, 1H), 4.25 (dt, J＝11.7, 2.1 Hz, 1H), 2.85—2.75 (m,
1H), 2.23—1.97 (m, 3H), 1.92 (s, 3H), 1.89—1.75 (m,
1H); 13C NMR (CDCl3, 75 MHz) δ: 165.6, 146.3, 137.2,
122.0, 120.4, 67.6, 35.6, 32.5, 29.2, 23.6; IR (KBr)－ν:
1
1719 (s), 1401 (w), 1258 ＋(m), 1097 (w), 1031 (w) cm ;
1
(m), 1401 (w), 1269 (m), 766 (m) cm ; MS (EI) m/z (%):
MS (EI) m/z (%): 164 ＋(M , 38.75), 91 (100); HRMS (EI)
calcd for C10H12O2 (M ) 164.0837, found 164.0836.
3,4,4a,5-Tetrahydroisochromen-1-one (4h) White
solid, 51% yield. 1H NMR (CDCl3, 300 MHz) δ: 7.29—
7.26 (m, 1H), 6.28—6.15 (m, 2H), 4.50—4.43 (m, 1H),
4.27 (dt, J＝11.7, 2.1 Hz, 1H), 2.85—2.74 (m, 1H),
2.41—2.30 (m, 1H), 2.06—1.95 (m, 2H), 1.89—1.77 (m,
1H); 13C NMR (CDCl3, 75 MHz) δ: 165.4, 135.9, 134.4,
125.1, 67.6, 32.1, 29.6, 29.1; IR (KBr) ν: 1715 (s), 1612
226 (M＋ , 97.92), 154 (100); HRMS (EI) calcd for
C15H14O2 (M＋) 226.0994, found 226.0991.
6-(4-Chlorophenyl)-3,4,4a,5-tetrahydroisochromen-
1
1-one (4c) White solid, 92% yield. H NMR (CDCl3,
300 MHz) δ: 7.45—7.32 (m, 5H), 6.55—6.51 (m, 1H),
4.53—4.47 (m, 1H), 4.30 (dt, J＝11.4, 2.4 Hz, 1H),
2.97—2.88 (m, 1H), 2.79—2.71 (m, 1H), 2.50—2.38 (m,
1H), 2.14—2.08 (m, 1H), 1.99—1.84 (m, 1H); 13C
NMR (CDCl3, 75 MHz) δ: 165.1, 143.4, 137.4, 136.5,
134.3, 128.7, 126.6, 124.2, 121.0, 67.6, 32.74, 32.71,
29.1; IR (KBr) ν: 1684 (s), 1542 (m), 1490 (w), 1268
－1
(m), 1247 (m), 1094 (m), 758 (m) cm ; MS (EI) m/z
(%): 150 (M＋, 26.55), 91 (100); HRMS (EI) calcd for
C9H10O2 (M＋) 150.0681, found 150.0679.
＋
－1
(w), 815 (m) cm ; MS (EI) m/z (%): 260 (M , 100);
HRMS (EI) calcd for C15H13O2Cl (M＋) 260.0604, found
260.0607.
Conclusion
In summary, a tandem intramolecular Michael addi-
tion/Wittig reaction has been developed for the synthe-
sis of fused cyclohexadiene derivatives, which were
important subunits in a number of biologically active
compounds, as well as versatile intermediates in organic
synthesis. The readily accessible starting material, mild
reaction conditions and reasonable yields made the pre-
sent reaction potentially useful in organic synthesis.
Further studies on the mechanism are under investiga-
tion in our laboratory.
6-(4-Bromophenyl)-3,4,4a,5-tetrahydroisochromen-
1-one (4d) White solid, 87% yield. H NMR (CDCl3,
1
300 MHz) δ: 7.51—7.48 (m, 2H), 7.41—7.34 (m, 3H),
6.55—6.53 (m, 1H), 4.53—4.47 (m, 1H), 4.30 (t, J＝
11.4 Hz, 1H), 2.98—2.87 (m, 1H), 2.79—2.70 (m, 1H),
2.51—2.39 (m, 1H), 2.14—2.08 (m, 1H), 1.98—1.85 (m,
1H); 13C NMR (CDCl3, 75 MHz) δ: 165.1, 143.5, 137.9,
136.5, 131.7, 126.9, 124.3, 122.6, 121.1, 67.6, 32.7,
32.6, 29.1; IR (KBr) ν: 1683 (s), 1542 (m), 1488 (w),
＋
－1
1269 (w), 812 (m) cm ; MS (EI) m/z (%): 304 (M ,
62.56), 152 (100); HRMS (EI) calcd for C15H13O2Br
(M＋) 304.0099, found 304.0103.
References
6-p-Tolyl-3,4,4a,5-tetrahydroisochromen-1-one (4e)
White solid, 79% yield. H NMR (CDCl3, 300 MHz) δ:
1
Wittig, G.; Geissler, G. Justus Liebigs Ann. Chem. 1953,
580, 44.
1
7.45—7.39 (m, 3H), 7.20—7.17 (m, 2H), 6.55—6.52 (m,
2
(a) Tang, Y.; Ye, S.; Sun, X.-L. Synlett 2005, 2720.
(b) Aggarwal, V. K.; Winn, C. L. Acc. Chem. Res. 2004, 37,
1H), 4.52—4.47 (m, 1H), 4.30 (t, J＝11.4 Hz, 1H),
Chin. J. Chem. 2010, 28, 1618— 1622
© 2010 SIOC, CAS, Shanghai, & WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
www.cjc.wiley-vch.de
1621

Wang et al.
FULL PAPER
611.
Chem., Int. Ed. 2008, 47, 3784.
(c) Dai, L.-X.; Hou, X.-L.; Zhou, Y.-G. Pure Appl. Chem.
1999, 71, 369.
(d) Vicario, J. L.; Reboredo, S.; Badia, D.; Carrillo, L.
Angew. Chem., Int. Ed. 2007, 46, 5168.
(d) Li, A.-H.; Dai, L.-X.; Aggarwal, V. K. Chem. Rev. 1997,
97, 2341.
6
(a) Jiang, Y.; Ma, D. Tetrahderon: Asymmetry 2002, 13,
1033.
3
(a) Tang, Y.; Ye, S.; Huang, Z.-Z.; Huang, Y.-Z. Heteroat.
Chem. 2002, 13, 463.
(b) Bernard, A. M.; Frongia, A.; Piras, P. P.; Secci, F.; Spiga,
M. Org. Lett. 2005, 7, 4565.
(b) Huang, Y.-Z.; Tang, Y.; Zhou, Z.-L. Tetrahedron 1998,
54, 1667.
(c) Yang, Z.; Fan, M.; Liu, W.; Liang, Y. Synthesis 2005,
2188.
(c) Deng, X.-M.; Cai, P.; Ye, S.; Sun, X.-L.; Liao, W.-W.;
Li, K.; Tang, Y.; Wu, Y.-D.; Dai, L.-X. J. Am. Chem. Soc.
2006, 128, 9730.
(d) Chuang, C.-P.; Tsai, A.-I. Synthesis 2006, 675.
(e) Zheng, J.-C.; Zhu, C.-Y.; Sun, X.-L.; Tang, Y.; Dai,
L.-X. J. Org. Chem. 2008, 73, 6909.
(d) Ye, S.; Huang, Z.-Z.; Xia, C.-A.; Tang, Y.; Dai, L.-X. J.
Am. Chem. Soc. 2002, 124, 2432.
(e) Zheng, J.-C.; Liao, W.-W.; Tang, Y.; Sun, X.-L.; Dai,
L.-X. J. Am. Chem. Soc. 2005, 127, 12222.
(f) Liao, W.-W.; Li, K.; Tang, Y. J. Am. Chem. Soc. 2003,
125, 13030.
(g) Papageorgious, C. D.; Cubillo de Dios, M. A.; Ley, S. V.;
Gaunt, M. J. Angew. Chem., Int. Ed. 2004, 43, 4641.
(h) Bremeyer, N.; Smith, S. C.; Ley, S. V.; Gaunt, M. J.
Angew. Chem., Int. Ed. 2004, 43, 2681.
(i) Papageorgious, C. D.; Ley, S. V.; Gaunt, M. J. Angew.
Chem., Int. Ed. 2003, 42, 828.
7
8
Lu, L.-Q.; Zhang, J.-J.; Li, F.; Cheng, Y.; An, J.; Chen, J.-R.;
Xiao, W.-J. Angew. Chem., Int. Ed. 2010, 49, 4495.
(a) Kumaran, G.; KulKarni, G. H. Synthesis 1995, 1545.
(b) Zhu, C.-Y.; Deng, X.-M.; Sun, X.-L.; Zheng, J.-C.; Tang,
Y. Chem. Commun. 2008, 738.
(a) Sun, X.-L.; Tang, Y. Acc. Chem. Res. 2008, 41, 937.
(b) Ye, L.-W.; Sun, X.-L.; Wang, Q.-G.; Tang, Y. Angew.
Chem., Int. Ed. 2007, 46, 5951.
(c) Wang, Q.-G.; Deng, X.-M.; Zhu, B.-H.; Ye, L.-W.; Sun,
X.-L.; Li, C.-Y.; Zhu, C.-Y.; Shen, Q.; Tang, Y. J. Am.
Chem. Soc. 2008, 130, 5408.
(d) Schomaker, J. M.; Pulgam, V. R.; Borhan, B. J. Am.
Chem. Soc. 2004, 126, 13600.
9
4
(a) Kokotos, C. G.; Aggarwal, V. K. Org. Lett. 2007, 9,
2099.
10 (a) Dauben, W. G.; Ipaktschi, J. J. Am. Chem. Soc. 1973, 95,
5088.
(b) Reddy Iska, V. B.; Gais, H.-J.; Tiwari, S. K.; Babu, G. S.;
Adrien, A. Tetrahedron Lett. 2007, 48, 7102.
(c) Robiette, R. J. Org. Chem. 2006, 71, 2726.
(d) Zheng, J.-C.; Liao, W.-W.; Sun, X.-X.; Sun, X.-L.; Tang,
Y.; Dai, L.-X.; Deng, J.-G. Org. Lett. 2005, 7, 5789.
(e) Liao, W.-W.; Deng, X.-M.; Tang, Y. Chem. Commun.
2004, 1516.
(f) Morton, D.; Pearson, D.; Field, R. A.; Stockman, R. A.
Org. Lett. 2004, 6, 2377.
(g) Aggarwal, V. K.; Vasse, J.-L. Org. Lett. 2003, 5, 3987.
(h) Yang, X.-F.; Zhang, M.-J.; Hou, X.-L.; Dai, L.-X. J. Org.
Chem. 2002, 67, 8097.
(b) Padwa, A.; Brodsky, L. J. Org. Chem. 1974, 39, 1318.
(c) Moorhoff, C. M. Synlett 1997, 126.
(d) Ye, L.-W.; Han, X.; Sun, X.-L.; Tang, Y. Tetrahedron
2008, 64, 8149.
(e) Ye, L.-W.; Wang, S.-B.; Wang, Q.-G.; Sun, X.-L.; Tang,
Y.; Zhou, Y.-G. Chem. Commun. 2009, 3092.
11 (a) Hong, B.-C.; Wu, M.-F.; Tseng, H.-C.; Huang, G.-F.; Su,
C.-F.; Liao, J.-H. J. Org. Chem. 2007, 72, 8459.
(b) Vosburg, D. A.; Weiler, S.; Sorensen, E. J. Angew.
Chem., Int. Ed. 1999, 38, 971.
(c) Maurinsh, Y.; Schraml, J.; Winter, H. D.; Blaton, N.;
Peeters, O.; Lescrinier, E.; Rozenski, J.; Van Aerschot, A.;
De Clercq, E.; Busson, R.; Herdewijn, P. J. Org. Chem.
1997, 62, 2861.
(d) Davies, S. G.; Bhalay, G. Tetrahedron: Asymmetry 1996,
7, 1595.
5
(a) Kim, C. H.; Jang, K. P.; Choi, S. Y.; Chung, Y. K.; Lee,
E. Angew. Chem., Int. Ed. 2008, 47, 4009.
(b) Huang, X.-C.; Liu, Y.-L.; Liang, Y.; Pi, S.-F.; Wang, F.;
Li, J.-H. Org. Lett. 2008, 10, 1525.
(c) Yar, M.; McGarrigle, E. M.; Aggarwal, V. K. Angew.
(E1006254 Li, L.; Zheng, G.)
1622
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