Enantioselective synthesis of spirocyclic cyclopentenes: Asymmetric [3+2] annulation of 2-arylideneindane-1,3-diones with MBH carbonates derivatives catalyzed by multifunctional thiourea-phosphines

Article abstract of DOI:10.1016/j.tet.2012.07.013

The [3+2] annulation reactions of 2-arylideneindane-1,3-diones with Morita-Baylis-Hillman (MBH) carbonates proceeded smoothly in the presence of multifunctional thiourea-phosphines to produce the corresponding quaternary carbon centered spirocyclic cyclop

Full text of DOI:10.1016/j.tet.2012.07.013

Tetrahedron 68 (2012) 7911e7919
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Enantioselective synthesis of spirocyclic cyclopentenes: asymmetric [3þ2]
annulation of 2-arylideneindane-1,3-diones with MBH carbonates derivatives
catalyzed by multifunctional thioureaephosphines
,b,
Fangle Hu a, Yin Wei b, Min Shi a
*
a Key Laboratory for Advanced Materials and Institute of Fine Chemicals, School of Chemistry & Molecular Engineering, East China University of Science and Technology,
130 Mei-Long Road, Shanghai 200237, China
b State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, China
a r t i c l e i n f o
a b s t r a c t
Article history:
The [3þ2] annulation reactions of 2-arylideneindane-1,3-diones with MoritaeBayliseHillman (MBH)
carbonates proceeded smoothly in the presence of multifunctional thioureaephosphines to produce the
corresponding quaternary carbon centered spirocyclic cyclopentenes in moderate yields, with high
diastereoselectivities and enantioselectivities under mild conditions. The plausible reaction has been also
discussed on the basis of previous literature.
Received 29 May 2012
Received in revised form 4 July 2012
Accepted 6 July 2012
Available online 20 July 2012
Ó 2012 Elsevier Ltd. All rights reserved.
1. Introduction
methyleneindolinones was disclosed by Barbas and his co-workers,
providing the corresponding spirocyclopentaneeoxindoles in good
1,3-Indanedione and its derivatives constitute a unique group of
compounds and attracted much attention of organic chemists and
biologists due to their characteristic features.1 Thus far, they have
been widely employed in the synthesis of drugs,2 in forensic
chemistry for fingerprint detection,3 in dyes and pigments,4 and in
semi- and photo-semiconductors,5 proving that 1,3-indanedione
and its derivatives are versatile starting materials for the synthe-
sis of potentially important compounds.
MortiaꢀBaylisꢀHillman (MBH) adducts have been also proven
to be suitable precursors for the synthesis of multifunctional cyclic
compounds, because the in situ generated phosphorus ylides from
MBH carbonates in the presence of tertiary phosphines are very
reactive 1,3-dipoles in a variety of annulations.6 In this field, Lu and
his co-workers first reported a series of intra- and intermolecular
[3þn] annulations (n¼2, 4, 6) using MBH carbonates as 1,3-dipoles
with various electron-deficient olefins catalyzed by a tertiary
phosphine, affording the corresponding cycloadducts in good
yields and high regioselectivities under mild conditions.7 More
recently, Zhang, Huang and He as well as their co-workers have also
developed several MBH adducts involved in [4þ1] annulations to
give the cycloaddition products in high yields, respectively.8
To the best of our knowledge, there are few reports about
asymmetric version of this reaction. The first report on the asym-
metric intermolecular [3þ2] cycloaddition of MBH carbonates with
yields and high ee values.9 Then, Lu’s group developed
L-threonine-
derived chiral phosphines and indicated that these chiral catalysts
were effective promoters in the asymmetric [3þ2] annulation of
MBH carbonates with isatylidenemalononitriles to deliver the op-
tically active cyclic products in high yields with high enantiose-
lectivities.10 With regard to the intramolecular [3þ2] annulation of
MBH carbonates with electron-deficient olefins, Tang and his co-
workers first utilized spirobiindane-based chiral phosphines as
catalysts to produce the corresponding intramolecular [3þ2] cyclic
adducts in good yields along with high ee values.11 Moreover, our
group has designed and synthesized a series of chiral multifunc-
tional thioureaephosphine catalysts derived from an axially chiral
binaphthyl scaffold and has also demonstrated that these chiral
phosphines were very effective catalysts in the asymmetric aza-
MBH reaction and asymmetric allylic substitution of MBH ad-
ducts, giving the corresponding products in good yields and ex-
cellent enantioselectivities as well as in the asymmetric [3þ2]
annulations of MBH carbonates with isatylidenemalononitriles,
giving the desired cycloadducts in good yields along with moderate
enantioselectivities.12e14 Recently, we have further developed
a series of multifunctional thioureaephosphine catalysts derived
from natural amino acid and applied them in asymmetric [3þ2]
annulation of MBH carbonates with trifluoroethylidenemalonates
to give corresponding highly functionalized trifluoromethyl
or pentafluoroethyl-bearing cyclopentenes in excellent yields
(upto >99%), high diastereoselectivities (upto 99:1) and enantio-
selectivities (upto 96%) under mild conditions.15 Herein as a part of
* Corresponding author. Fax: þ86 21 64166128; e-mail address: Mshi@mail.sio-
c.ac.cn (M. Shi).
0040-4020/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.tet.2012.07.013

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F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
our continuing interest in asymmetric annulation catalyzed by
multifunctional thioureaephosphines, we wish to report the
asymmetric annulation of 2-arylideneindane-1,3-diones 1 with
reaction outcome, it was found that adding organic base, such as
triethylamine or 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP) could not
improve the reaction outcome (Table 2, entries 12 and 13). If the
[3þ2] annulation was conducted using Brønsted acid, such as
benzoic acid or acetic acid as additives, the reaction could not occur,
suggesting that proton acid could destroy the formation of the in
situ generated phosphorus ylides from MBH carbonates in the
presence of tertiary phosphines (Table 2, entries 14 and 15). The
solvent effects have been also examined using TP3 as the catalyst in
chlorobenzene, (trifluoromethyl)benzene, and mixed solvent (tol-
uene/chloroform), but the ee value and yield of 3a decreased re-
markably (Table 2, entries 16e18). Therefore, the best reaction
conditions have been determined as that TP3 (20 mol %) should be
used as the catalyst and the reaction should be carried out in tol-
uene at 0 ꢁC without any additives.
Having determined the optimal reaction conditions, we next
turned our attention to the scope of the asymmetric [3þ2] annu-
lation of 2-arylideneindane-1,3-diones 1 with MBH carbonates 2
and the results are summarized in Table 3. Substrates with an
electron-withdrawing substituent on the aromatic ring of MBH
carbonates afforded the corresponding annulation adducts in
moderate yields with excellent diastereo- and enantioseletivities
using TP3 or TP4 (Table 3, entries 1e9). As for substrates 2f and 2g,
in which the substituents at the ortho position of the aromatic ring
of MBH carbonates, the corresponding products were acquired
with high ee upto 97%, respectively (Table 3, entries 5 and 6). When
two electron-withdrawing substituents were introduced to the
aromatic ring of MBH carbonates, the reaction could proceed
smoothly to give the annulation adducts in moderate yields and
good ee values (Table 3, entries 10e14). Especially when the sub-
stituents were introduced at 2, 3- or 2, 4-position of the aromatic
ring of MBH carbonates, the corresponding annulation adducts
were obtained in 96% ee and 98% ee, respectively (Table 3, entries
10 and 11). While when the substituents were introduced at 2, 6-
position, the yield and ee value decreased remarkably due to the
steric hindrance (Table 3, entry 13). Owing to the lower activities at
0 ꢁC, substrate with electron-donating substituent on the aromatic
ring of MBH carbonate afforded the trace product (Table 3, entry
15). We next examined R1 moiety of electron-deficient olefins de-
rived from 1,3-indanedione. Whether an aryl or alkyl group was
introduced, the reaction could proceed smoothly to give the cor-
responding cycloadducts 3pe3s in moderate yields and ee values
within 48 h using TP3 or TP4 (Table 3, entries 16e19).
MBH carbonates
2
catalyzed by multifunctional thiour-
eaephosphines to afford the corresponding quaternary carbon
centered spirocyclic cyclopentenes in moderate yields, high
diastereoselectivities, and enantioselectivities under mild
conditions.16
2. Results and discussion
Initially, we examined the reaction of 2-(4-nitrobenzylidene)
indan-1,3-dione 1a (0.1 mmol, 1.0 equiv) with MBH carbonate 2a
(0.2 mmol, 2.0 equiv) catalyzed by PPh3 in THF (2 mL) at room
temperature, the C-1 addition product 3a was obtained in 74% yield
along with excellent diastereoselectivities (upto >99% dr) within
24 h. Based on the preliminary investigation on [3þ2] annulation of
2-(4-nitro-benzylidene)-indan-1,3-dione 1a with MBH carbonate
2a, asymmetric version of this reaction was subsequently exploited.
Primarily, we utilized bifunctional chiral phosphine derived from
an axially chiral binaphthyl scaffold TP1 as a catalyst for the [3þ2]
annulation of electron-deficient alkene 1a with MBH carbonate 2a
in toluene, giving the product 3a in 39% yield along with 19% ee
(Table 1, entry 1). In order to improve the yield and enantiose-
lectivity, other multifunctional thioureaephosphines TPs, derived
from natural amino acids were further tested for this [3þ2] annu-
lation. To our delight, TP2 derived from
L-valine was used to cata-
lyze the reaction in toluene (2 mL) within 24
h
at room
temperature, furnishing 3a in 59% yield and 65% ee (Table 1, entry
2). We continued examining multifunctional thioureaephosphines
with more sterically hindered substituents TP3eTP6. TP3 could
promote the reaction very well, producing 3a in 94% yield along
with 75% ee value and TP4 is the best catalyst in terms of enan-
tioselectivity, affording 3a in 88% yield along with 78% ee value
(Table 1, entries 3 and 4). However, increasing the steric hindrance
of thiourea moiety did not further increase the enantioselectivities
(Table 1, entries 5 and 6). In order to obtain better result, we syn-
thesized multifunctional squaramideephosphines TP7eTP9 de-
rived from natural amino acid according to the previous
literature13s to catalyze the [3þ2] annulation, however, furnishing
3a in moderate yield along with low ee value (Table 1, entries 7e9).
Having identified the best catalyst, we subsequently optimized
the reaction conditions, such as temperature, solvent, and additive
using TP3 as catalyst, 1a and 2a as substrates. Initially we carried
out the reaction of 1a (0.1 mmol, 1.0 equiv) with 2a (0.2 mmol,
Their structures have been determined by 1H and 13C NMR
spectroscopic data, MS, and HRMS analyses. The absolute config-
uration of 3k has been unambiguously determined by X-ray dif-
fraction. The ORTEP drawing of 3k is shown in Fig. 1 and its CIF data
are presented in the Supplementary data (for details see Supple-
mentary data).
ꢀ
2.0 equiv) in toluene (2.0 mL) at room temperature using 4 A MS as
additive, affording 3a in 99% yield and 73% ee value, suggesting that
ꢀ
4 A MS could promote the yield, but slightly decrease the ee value
(Table 2, entry 1). We next examined the reaction at 0 ꢁC, producing
3a in 30% yield along with 85% ee within 144 h (Table 2, entry 2).
We believed that the poor solubility of 1a in toluene decreased the
yield remarkably at low reaction temperature. Other solvents, such
as DCM (dichloromethane), chloroform, and o-xylene were exam-
ined under the same conditions, but these solvents could not im-
prove reaction outcomes (Table 2, entries 3e5). In order to increase
the solubility of 1a in toluene at 0 ꢁC, the reaction was conducted in
10 mL of toluene, affording 3a in 70% yield along with 89% ee (Table
2, entry 6) and increasing the employed amount of 1a or 2a de-
crease the ee value (Table 2, entries 7 and 8). We subsequently used
TP4 as catalyst to further examine the [3þ2] annulation under the
standard conditions, indicating that TP4 could also facilitate the
[3þ2] annulation to give 3a in 80% yield and 88% ee value (Table 2,
entry 9). Decreasing the temperature to ꢀ10 ꢁC or increasing the
temperature to 5 ꢁC was detrimental to the ee value of 3a, affording
3a in 86% ee value and 82% ee value, respectively (Table 2, entries 10
and 11). Next, we attempted to add some additives to improve the
The mechanism of this interesting [3þ2] reaction is proposed in
Scheme 1 on the basis of previous literature.7a,14e,17 Initially the
multifunctional thioureaephosphine TP3 attacks from b position of
MBH carbonates to take off carbon dioxide and tert-butyl alcohol,
producing phosphorus ylide A, which undergoes the nucleophilic
attack with the C-1 carbon center to the electron-deficient olifin 1
to give the corresponding intermediate B. Subsequent Michael
addition produces cyclic intermediate C, which produces 3 and
regenerates TP3 via elimination of multifunctional thiour-
eaephosphine TP3. The high regio-, diastereo-, and enantiose-
lectivity of this reaction are probably controlled by steric hindrance
between benzyl group and benzhydryl group on the catalyst with
2-arylideneindane-1,3-dione 1 as shown in Scheme 1.
In conclusion, a fairly efficient [3þ2] annulation reaction of
2-arylideneindane-1,3-diones with MBH carbonates catalyzed by
multifunctional thioureaephosphine has been developed, which
provides an easy access to the synthesis of the corresponding

F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
7913
Table 1
Screening of catalysts for the asymmetric [3þ2] annulation
Entrya
Catalyst
Time (h)
Yield of 3a (%)b
ee of 3a (%)c
1
2
3
4
5
6
7
8
9
TP1
TP2
TP3
TP4
TP5
TP6
TP7
TP8
TP9
24
24
24
24
24
24
24
24
24
39
59
94
88
92
19
65
75
78
70
74
25
40
ꢀ32
80
71d
39d
53d
a
The reaction was carried out using 1a (0.1 mmol), 2a (0.2 mmol) and catalyst (0.02 mmol) in toluene (2.0 mL).
Isolated yield with a dr (diastereoselective ratio) value>99:1 if not otherwise specified.
Determined by chiral HPLC analysis.
b
c
d
The reaction was carried out in chloroform (5.0 mL).
quaternary carbon centered spirocyclic cyclopentenes under mild
3. Experimental section
3.1. General remarks
reaction conditions in moderate to good yields (upto 75%), with
high diastereoselectivities (upto >99:1) and enantioselectivities
(upto 98%). Efforts are in progress to elucidate the mechanistic
details of this reaction and use the multifunctional thiour-
eaephosphines in other asymmetric reactions.
Melting points were determined on a digital melting point ap-
paratus and temperatures were uncorrected. Optical rotations were

7914
F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
Table 2
Optimization of reaction conditions for the asymmetric [3þ2] annulation
Entrya
Solvent
Temperature (ꢁC)
Additive
Yield of 3a (%)b
ee of 3a (%)c
1d
2d
3d
4d
5d
6
Toluene
Toluene
CHCl3
DCM
o-Xylene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
25
0
0
0
0
0
0
0
0
4 A MS
/
/
/
/
/
/
/
99
30
40
78
67
70
78
78
80
47
75
67
73
85
78
62
69
89
86
84
88
86
82
82
89
dh
dh
70
75
60
7e
8f
9g
10
11
12
13
14
15
16
17
18
/
/
/
ꢀ10
5
0
0
0
0
0
0
0
Et3N
HFIP
4-Nitrophenol
Benzoic acid
/
/
/
65
Trace
Trace
60
45
47
Chlorobenzene
(Trifluoromethyl)benzene
Toluene/CHCl3 (10/1)
a
The reaction was carried out by employing 1a (0.1 mmol), 2a (0.2 mmol) and solvent (10 mL) at 0 ꢁC within 144 h.
Isolated yield.
Determined by Chiral HPLC.
The reaction was conducted in 2 mL solvent.
2a (3.0 equiv) was used.
1a (0.2 mmol) and 2a (0.1 mmol) were used.
Catalyst TP4 was used.
b
c
d
e
f
g
h
Not determined.
determined at 589 nm (sodium D line) by using a PerkineElmer-
341 MC digital polarimeter; [ ]D-values are given in unit of
MBH carbonates (0.2 mmol), catalyst (0.02 mmol), and toluene
(10 mL). The reaction mixture was stirred at 0 ꢁC for 144 h, then the
solvent was removed under reduced pressure and the residue was
purified by flash column chromatography.
Catalysts TP1, TP2, TP3, TP4, and TP5 were synthesized according
to the previous literature15 and the preparation of new catalysts TB6,
TB7, and TB8 can be found in the Supplementary data.
a
10 degꢀ1 cm2 gꢀ1 1H NMR spectra were recorded on a Varian
Mercury-300 and 400 spectrometer for solution in CDCl3 with tet-
ramethylsilane (TMS) as an internal standard; coupling constants J
are given in Hertz. 13C NMR spectra were recorded on a Varian
Mercury-300 and 400 spectrophotometers (75 or 100 MHz) with
complete proton decoupling spectrophotometers (CDCl3: 77.0 ppm).
Infrared spectra were recorded on a PerkineElmer PE-983 spec-
trometer with absorption in cmꢀ1. Flash column chromatography
was performed using 300e400 mesh silica gel. For thin-layer chro-
matography (TLC), silica gel plates (Huanghai GF254) were used.
Chiral HPLC was performed on a SHIMADZU SPD-10A vp series with
chiral columns (Chiralpak AD-H, OD-H, and IC-H columns
4.6ꢂ250 mm, (Daicel Chemical Ind., Ltd.)) and chiral column (Phe-
3.2.1. (S)-3-(Butylamino)-4-((1-(diphenylphosphino)-3-
phenylpropan-2-yl)amino)cyclobut-3-ene-1,2-dione (TP7). A white
solid, Mp: 251e252 ꢁC. 1H NMR (DMSO-d6, 400 MHz, TMS)
d 0.89 (t,
J¼7.2 Hz, 3H, CH3), 1.25e1.31 (m, 2H, CH2), 1.44 (br, 2H, CH2),
2.35e2.42 (m, 1H, CH), 2.50e2.53 (m, 1H, CH), 2.90e3.02 (m, 2H,
CH2), 3.34e3.43 (m, 4H), 4.20 (br, 1H, CH), 7.10e7.43 (m, 15H, Ar).
31P NMR (161.93 MHz, DMSO-d6, 85% H3PO4):
d
ꢀ18.68. IR (CH2Cl2)
nomenex Lux 5
m
Amylose-2 column 4.6ꢂ250 mm (PA-2), Phenom-
n 1026, 1091, 1231, 1352, 1431, 1475, 1560, 1636, 1802, 2875,
enex Lux 5
m
Cellulose-2 column 4.6ꢂ250 mm (PC-2), (Phenomenex
2928 cmꢀ1. MS (ESI) m/e 471.1 (Mþþ1). HRMS (ESI) calcd for
Ind., Ltd.)). Mass spectra were recorded by EI, ESI, MALDI, and HRMS
was measured on a HP-5989 instrument.
C29H31N2O2P: 470.2123. Found: 470.2118.
3.2.2. (S)-3-(Cyclohexylamino)-4-((1-(diphenylphosphino)-3-
phenylpropan-2-yl)amino)cyclobut-3-ene-1,2-dione (TP8). A white
solid, Mp:285e286 ꢁC. 1H NMR (DMSO-d6, 400 MHz, TMS)
3.2. General procedure for the asymmetric [3D2] annulation
reaction of MBH carbonates with 2-arylidene-indane-1,3-dione
d
1.12e1.32 (m, 6H, CH2), 1.52e1.56 (m, 1H, CH), 1.65 (br, 2H, CH2),
Into a 25 mL oven-dried reaction flask under Ar gas protection
were added, 2-benzylidene-1H-indene-1,3(2H)-dione (0.1 mmol),
1.82e1.84 (m, 2H, CH2), 2.32e2.44 (m, 2H, CH2), 2.90e3.04 (m, 2H,
CH2), 3.35 (s, 2H), 3.67 (br, 1H, NH), 4.21 (br, 1H, CH), 7.14e7.34 (m,

F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
7915
Table 3
Substrate scope for the asymmetric [3þ2] annulation
Entrya
R1
R2
Yield (%)b
ee (%)c
1
2
3
4
5
6
7
8
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1a, 4-NO2C6H4
1b, C6H5
2b, 4-Cl
2c, 4-Br
2d, 4-CN
2e, 4-CF3
2f, 2-Cl
2g, 2-Br
2h, 3-NO2
2i, 3-Cl
3b, 52
3c, 51
3d, 65
3e, 50
3f, 68
3g, 50
3h, 75
3i, 60
88d
92
91d
91
97
97
87
91
90d
96
98
92
92
90
9
2j, 3-Br
3j, 51
3k, 62
3l, 67
10
11
12
13
14
15
16
17
18
19
2k, 2,4-Cl2
2l, 2,3-Cl2
2m, 3,4-Cl2
2n, 2,6-Cl2
2o, 4-F, 3-Br
2p, 4-CH3
2a, 4-NO2
2a, 4-NO2
2a, 4-NO2
2a, 4-NO2
3m, 54
3n, 30
3o, 50
Trace
df
3p, 75e
3q, 64e
3r, 75e
3s, 68e
66d
67d
65
1c, 3-BrC6H4
1d, 4-BrC6H4
1e, Cyclohexyl
ꢀ67
a
The reaction was carried out by employing 1 (0.1 mmol), 2 (0.2 mmol) and toluene (10 mL) at 0 ꢁC within 144 h.
b
c
d
e
f
Isolated yield.
Determined by Chiral HPLC.
Catalyst TP4 was used.
The reaction was carried out within 48 h.
Not determined.
Fig. 1. X-ray crystal structure of 3k.

7916
F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
Scheme 1. A proposed mechanism.
15H, Ar). 31P NMR (161.93 MHz, DMSO-d6, 85% H3PO4):
d
ꢀ18.84. IR
J¼7.2 Hz 1H, CH2), 4.13 (dq, J¼11.2 Hz, J¼7.2 Hz, 1H, CH2), 4.23 (d,
J¼10.4 Hz, 1H, CH), 4.99 (dd, J¼10.4 Hz, J¼2.4 Hz, 1H, CH), 6.60 (d,
J¼2.4 Hz, 1H,]CH), 7.12e7.14 (m, 1H, Ar), 7.16e7.23 (m, 3H, Ar),
7.31 (d, J¼8.8 Hz, 2H, Ar), 7.50e7.81 (m, 2H, Ar), 7.83e7.94 (m, 1H,
Ar), 7.96 (d, J¼8.8 Hz, 2H, Ar), 8.01 (d, J¼7.2 Hz, 1H, Ar). 13C NMR
(CH2Cl2)
n 1030, 1242, 1372, 1433, 1471, 1553, 1637, 1790, 2842,
2932 cmꢀ1. MS (ESI) m/e 497.1 (Mþþ1). HRMS (ESI) calcd for
C31H33N2O2P: 496.2280. Found: 496.2271.
3.2.3. (S)-3-(Benzhydrylamino)-4-((1-(diphenylphosphino)-3-
phenylpropan-2-yl)amino)cyclobut-3-ene-1,2-dione (TP9). A white
solid, Mp: 297e298 ꢁC. 1H NMR (DMSO-d6, 400 MHz, TMS)
(CDCl3, 100 MHz, TMS)
d 13.9, 53.8, 60.9, 61.5, 71.5, 123.6, 123.7,
128.8, 128.9, 129.9, 133.1, 136.5, 136.7, 138.1, 139.5, 141.5, 141.7,
142.4, 144.7, 147.3, 163.0, 197.9, 199.2. IR (CH2Cl2) n 909, 1014, 1095,
1168, 1231, 1344, 1492, 1518, 1597, 1702, 2875, 2978 cmꢀ1. MS (ESI)
m/e 502.0 (Mþþ1). HRMS (MALDI) calcd for C28H20NO6ClNa:
524.0880. Found: 524.0871; Enantiomeric excess was determined
d
2.36e2.43(m,1H, CH),2.54e2.57(m,1H, CH),2.89e2.94(m,1H, CH),
3.02e3.07 (m,1H, CH), 4.25 (br,1H, CH), 6.32 (s,1H, CH), 7.14e7.41 (m,
25H, Ar), 8.02 (br, 1H, NH). 31P NMR (161.93 MHz, DMSO-d6, 85%
H3PO4):
d
ꢀ18.63. IR (CH2Cl2)
n 1006, 1009, 1201, 1358, 1434, 1455,
by HPLC with a Chiralcel OD-H column [
l
¼230 nm; eluent: Hex-
1548,1638,1799, 3021, 3143 cmꢀ1. MS (ESI) m/e 581.2 (Mþþ1). HRMS
ane/Isopropanol¼60/40;
Flow
rate:
0.50
mL/min;
tmajor¼31.13 min, tminor¼40.67 min; ee%¼88%; ½a D20
ꢃ
¼þ183.4 (c 1.0,
(ESI) calcd for C38H33N2O2P: 580.2280. Found: 580.2277.
CH2Cl2)].
3.2.4. Compound 3a. A white solid, Mp: 225e226 ꢁC. 1H NMR
(CDCl3, 300 MHz, TMS)
d
1.11 (t, J¼7.2 Hz, 3H, CH3), 4.03e4.15 (m,
3.2.6. Compound 3c. A white solid, Mp: 168e169 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
2H, CH2), 4.23 (d, J¼10.2 Hz, 1H, CH), 5.14 (dd, J¼10.2 Hz, J¼1.2 Hz,
1H, CH), 6.68 (d, J¼1.2 Hz, 1H,]CH), 7.33 (d, J¼8.7 Hz, 2H, Ar), 7.43
(d, J¼8.7 Hz, 2H, Ar), 7.80e7.90 (m, 3H, Ar), 7.97 (d, J¼8.7 Hz, 2H,
Ar), 8.03 (d, J¼7.2 Hz, 1H, Ar), 8.15 (d, J¼8.7 Hz, 2H, Ar). 13C NMR
d
1.10 (t, J¼7.2 Hz, 3H, CH3), 4.05 (dq,
J¼11.2 Hz, J¼7.2 Hz, 1H, CH), 4.12 (dq, J¼11.2 Hz, J¼7.2 Hz, 1H,
CH), 4.19 (d, J¼10.4 Hz, 1H, CH), 4.99 (dd, J¼10.4 Hz, J¼2.8 Hz, 1H,
CH), 6.59 (d, J¼2.8 Hz, 1H,]CH), 7.12 (d, J¼8.8 Hz, 2H, Ar), 7.30 (d,
J¼8.8 Hz, 2H, Ar), 7.39 (d, J¼8.8 Hz, 2H, Ar), 7.75e7.81 (m, 2H, Ar),
7.83e7.87 (m, 1H, Ar), 7.95 (d, J¼8.8 Hz, 2H, Ar), 8.01 (d,
(CDCl3, 75 MHz, TMS) d 13.9, 54.1, 61.1, 61.2, 71.5, 123.7, 123.8, 124.0,
128.3, 129.9, 136.7, 136.8, 139.2, 141.5, 141.6, 141.7, 143.8, 147.2, 147.4,
148.7, 162.6, 197.5, 198.9. IR (CH2Cl2)
n 911, 1012, 1100, 1168, 1233,
J¼7.6 Hz, 1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d 13.9, 53.9,
1270, 1343, 1515, 1599, 1701, 1721, 2850, 2927 cmꢀ1. MS (ESI) m/e
535.0 (MþþNa). HRMS (ESI) calcd for C28H20N2NaO8: 535.1112.
Found: 535.1110; Enantiomeric excess was determined by HPLC
60.9, 61.4, 71.4, 121.2, 123.5, 123.7, 129.1, 129.9, 131.8, 136.5, 136.6,
138.2, 140.1, 141.5, 141.7, 142.4, 144.6, 147.3, 163.0, 197.8, 199.2.
IR (CH2Cl2)
n 908, 1010, 1168, 1232, 1269, 1344, 1488, 1519, 1597,
with a Chiralcel OD-H column [
l
¼230 nm; eluent: Hexane/Iso-
1703, 1744, 2870, 2958 cmꢀ1. MS (ESI) m/e 546.0 (Mþþ1).
propanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼37.67 min,
tminor¼58.60 min; ee%¼89%; ½a D20
ꢃ
¼þ206.7 (c 1.0, CH2Cl2)].
HRMS
(MALDI)
calcd
for
C28H20NO6BrNa:
568.0379. Found: 568.0366; Enantiomeric excess was de-
termined by HPLC with a Chiralcel OD-H column [
¼230 nm;
eluent: Hexane/Isopropanol¼60/40; Flow rate: 0.50 mL/min;
3.2.5. Compound 3b. A white solid, Mp: 86e87 ꢁC. 1H NMR (CDCl3,
400 MHz, TMS)
1.09 (t, J¼7.2 Hz, 3H, CH3), 4.04 (dq, J¼11.2 Hz,
l
d

F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
7917
tmajor¼39.58 min, tminor¼51.38 min; ee%¼93%; ½a D20
ꢃ
¼þ198.5 (c
568.0362. Found: 568.0366; Enantiomeric excess was determined
by HPLC with a Chiralcel OD-H column [
¼230 nm; eluent: Hexane/
1.0, CH2Cl2)].
l
Isopropanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼44.42 min,
3.2.7. Compound 3d. A white solid, Mp: 135e136 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
tminor¼56.46 min; ee%¼97%; ½a D20
ꢃ ¼þ229.8 (c 1.0, CH2Cl2)].
d
1.10 (t, J¼7.2 Hz, 3H, CH3), 4.01e4.16 (m,
2H, CH2), 4.20 (d, J¼10.0 Hz, 1H, CH), 5.08 (dd, J¼10.0 Hz, J¼2.0 Hz,
1H, CH), 6.66 (d, J¼2.0 Hz, 1H,]CH), 7.31 (d, J¼8.4 Hz, 2H, Ar), 7.37
(d, J¼8.4 Hz, 2H, Ar), 7.58 (d, J¼8.4 Hz, 2H, Ar), 7.77e7.83 (m, 2H,
Ar), 7.85e7.89 (m, 1H, Ar), 7.97 (d, J¼8.4 Hz, 2H, Ar), 8.02 (d,
3.2.11. Compound 3h. A white solid, Mp: 116e117 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
d
1.10 (t, J¼7.2 Hz, 3H, CH3), 4.01e4.16 (m,
2H, CH2), 4.25 (d, J¼8.4 Hz, 1H, CH), 5.15 (dd, J¼8.4 Hz, J¼2.0 Hz, 1H,
CH), 6.68 (d, J¼2.0 Hz, 1H,]CH), 7.34 (d, J¼8.8 Hz, 2H, Ar),
7.46e7.50 (m, 1H, Ar), 7.61 (d, J¼7.6 Hz, 1H, Ar), 7.77e7.83 (m, 2H,
Ar), 7.85e7.89 (m, 1H, Ar), 7.97 (d, J¼8.8 Hz, 2H, Ar), 8.03 (d,
J¼7.6 Hz, 1H, Ar), 8.08e8.12 (m, 2H, Ar). 13C NMR (CDCl3, 100 MHz,
J¼7.6 Hz, 1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d 13.8, 54.3, 61.0,
61.2, 71.5, 111.2, 118.5, 123.6, 123.8, 128.2, 129.8, 132.5, 136.6, 136.8,
139.0, 141.4, 141.6, 141.8, 143.9, 146.6, 147.4, 162.6, 197.5, 198.9. IR
(CH2Cl2)
n
1015, 1095, 1144, 1168, 1233, 1271, 1345, 1519, 1596, 1703,
TMS) d 13.9, 53.9, 61.0, 61.2, 71.4, 122.47, 122.5, 123.7, 123.8, 129.7,
2868, 2934 cmꢀ1. MS (ESI) m/e 493.0 (Mþþ1). HRMS (MALDI) calcd
129.9,133.7,136.6,136.8,139.2,141.5,141.7,141.8,143.2,143.8,144.6,
for C29H20N2NaO6: 515.1208. Found: 515.1214; Enantiomeric excess
147.4, 148.4, 162.6, 197.5, 198.8. IR (CH2Cl2) n 908, 1012, 1093, 1170,
was determined by HPLC with
¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow rate:
0.50 mL/min; tmajor¼56.47 min, tminor¼88.75 min; ee%¼91%;
a 2D0
¼þ200.3 (c 1.0, CH2Cl2)].
a
Chiralcel OD-H column
1231, 1268, 1344, 1520, 1595, 1702, 1741, 2857, 2929 cmꢀ1. MS (ESI)
m/e 535.0 (MþþNa). HRMS (ESI) calcd for C28H20N2O8Na: 535.1112.
Found: 535.1099; Enantiomeric excess was determined by HPLC
[
l
½
ꢃ
with a Chiralcel OD-H column [
l
¼230 nm; eluent: Hexane/Iso-
propanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼41.67 min,
3.2.8. Compound 3e. A white solid, Mp: 184e185 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
tminor¼63.17 min; ee%¼87%; ½a D20
ꢃ ¼þ210.2 (c 1.0, CH2Cl2)].
d
1.08 (t, J¼7.2 Hz, 3H, CH3), 4.04 (dq,
J¼10.8 Hz, J¼7.2 Hz, 1H, CH), 4.12 (dq, J¼10.8 Hz, J¼7.2 Hz, 1H, CH),
4.23 (d, J¼10.4 Hz, 1H, CH), 5.09 (dd, J¼10.4 Hz, J¼2.0 Hz, 1H, CH),
6.64 (d, J¼2.0 Hz, 1H,]CH), 7.32 (d, J¼8.4 Hz, 2H, Ar), 7.37 (d,
J¼8.0 Hz, 2H, Ar), 7.53 (d, J¼8.0 Hz, 2H, Ar), 7.76e7.82 (m, 2H, Ar),
7.84e7.88 (m, 1H, Ar), 7.96 (d, J¼8.4 Hz, 2H, Ar), 8.02 (d, J¼7.6 Hz,
3.2.12. Compound 3i. A white solid, Mp: 115e116 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
d
1.09 (t, J¼7.2 Hz, 3H, CH3), 4.00e4.08 (m,
1H, CH2), 4.09e4.17 (m, 1H, CH2), 4.23 (d, J¼10.0 Hz, 1H, CH), 4.99
(d, J¼10.0 Hz, 1H, CH), 6.61 (s, 1H,]CH), 7.13e7.27 (m, 4H, Ar), 7.31
(d, J¼8.4 Hz, 2H, Ar), 7.75e7.81 (m, 2H, Ar), 7.83e7.87 (m, 1H, Ar),
7.96 (d, J¼8.4 Hz, 2H, Ar), 8.02 (d, J¼7.6 Hz, 1H, Ar). 13C NMR (CDCl3,
1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d 13.8, 54.1, 60.9, 61.4, 71.5,
123.6, 123.8, 124.0 (q, J¼270.2 Hz), 125.7 (d, J¼3.8 Hz), 127.8, 129.5
100 MHz, TMS) d 13.8, 53.9, 60.8, 61.3, 71.5,123.6,123.7,125.8,127.5,
(q, J¼32.4 Hz), 129.9, 136.6, 137.7, 138.6, 141.5, 141.7, 142.2, 144.3,
127.6, 129.87, 129.9, 134.5, 136.5, 136.6, 138.2, 141.5, 141.7, 142.3,
145.2, 147.3, 162.8, 197.7, 199.1. 19F NMR (376 MHz, CFCl3)
d
ꢀ62.6. IR
143.1, 144.5, 147.3, 162.9, 197.8, 199.1. IR (CH2Cl2) n 910, 1016, 1094,
(CH2Cl2)
n
835, 1019, 1069, 1112, 1156, 1234, 1323, 1370, 1520, 1597,
1170, 1233, 1343, 1495, 1520, 1599, 1703, 2876, 2980 cmꢀ1. MS (ESI)
m/e 524.0 (MþþNa). HRMS (MALDI) calcd for C28H20NO6ClNa:
524.0882. Found: 524.0871; Enantiomeric excess was determined
1705, 2850, 2930 cmꢀ1. MS (ESI) m/e 536.0 (Mþþ1). HRMS (MALDI)
calcd for C29H20NO6F3Na: 558.1141. Found: 558.1135; Enantiomeric
excess was determined by HPLC with a Chiralcel OD-H column
by HPLC with a Chiralcel OD-H column [
l
¼230 nm; eluent: Hexane/
[
l
¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow rate:
0.50 mL/min; tmajor¼31.74 min, tminor¼40.70 min; ee%¼90%;
a 2D0
¼þ197.0 (c 1.0, CH2Cl2)].
Isopropanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼32.60 min,
tminor¼45.33 min; ee%¼91%; ½a D20
ꢃ ¼þ214.2 (c 1.0, CH2Cl2)].
½
ꢃ
3.2.13. Compound 3j. A white solid, Mp: 104e105 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
3.2.9. Compound 3f. A white solid, Mp: 106e107 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
d
1.09 (t, J¼7.2 Hz, 3H, CH3), 4.04 (dq,
d
1.04 (t, J¼7.2 Hz, 3H, CH3), 3.99e4.11 (m,
J¼11.2 Hz, J¼7.2 Hz, 1H, CH), 4.14 (dq, J¼11.2 Hz, J¼7.2 Hz, 1H, CH),
4.23 (d, J¼10.4 Hz, 1H, CH), 5.14 (dd, J¼10.4 Hz, J¼2.0 Hz, 1H, CH),
6.68 (d, J¼2.0 Hz, 1H,]CH), 7.12e7.19 (m, 2H, Ar), 7.31 (d, J¼8.8 Hz,
2H, Ar), 7.33e7.35 (m, 1H, Ar), 7.38e7.39 (m, 1H, Ar), 7.75e7.81 (m,
2H, Ar), 7.83e7.87 (m, 1H, Ar), 7.96 (d, J¼8.8 Hz, 2H, Ar), 8.02 (d,
2H, CH2), 4.30 (d, J¼7.2 Hz, 1H, CH), 5.72 (d, J¼7.2 Hz, 1H, CH), 6.61
(s, 1H,]CH), 7.12e7.16 (m, 1H, Ar), 7.26e7.28 (m, 2H, Ar), 7.37 (d,
J¼8.8 Hz, 2H, Ar), 7.49 (d, J¼6.4 Hz, 1H, Ar), 7.75e7.81 (m, 2H, Ar),
7.83e7.86 (m, 1H, Ar), 7.93 (d, J¼8.8 Hz, 2H, Ar), 8.01 (d, J¼7.2 Hz,
1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d
13.7, 49.2, 60.8, 61.7, 71.6,
J¼7.2 Hz, 1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d 13.8, 53.9, 60.9,
61.3, 71.5, 122.7, 123.6, 123.7, 126.3, 129.9, 130.2, 130.5, 136.5, 136.6,
138.2, 141.5, 141.7, 142.3, 143.3, 144.5, 147.3, 162.9, 197.8, 199.1. IR
123.2, 123.66, 123.7, 127.5, 128.1, 128.3, 129.4, 130.1, 134.1, 136.4,
136.6, 137.9, 139.2, 141.6, 141.7, 142.4, 145.3, 147.3, 162.8, 197.7, 199.4.
IR (CH2Cl2)
n
856, 908,1034,1096,1233,1269,1345,1475,1519,1597,
(CH2Cl2) n 905, 1010, 1096, 1231, 1268, 1345, 1490, 1518, 1598, 1702.
1704, 1744, 2852, 2924 cmꢀ1. MS (ESI) m/e 524.0 (MþþNa). HRMS
(ESI) calcd for C28H20ClNNaO6: 524.0871. Found: 524.0872; Enan-
tiomeric excess was determined by HPLC with a Chiralcel OD-H
2930 cmꢀ1. MS (ESI) m/e 568.0 (MþþNa). HRMS (MALDI) calcd for
C28H20NO6BrNa: 568.0369. Found: 568.0366; Enantiomeric excess
was determined by HPLC with
¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow rate:
0.50 mL/min; tmajor¼40.66 min, tminor¼55.19 min; ee%¼90%;
a 2D0
¼þ186.3 (c 1.0, CH2Cl2)].
a Chiralcel OD-H column
column [
rate: 0.50 mL/min; tmajor¼30.87 min, tminor¼37.24 min; ee%¼97%;
a 2D0
¼þ243.8 (c 1.0, CH2Cl2)].
l
¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow
[l
½
ꢃ
½ ꢃ
3.2.10. Compound 3g. A white solid, Mp: 119e120 ꢁC. 1H NMR
(CDCl3, 300 MHz, TMS)
3.2.14. Compound 3k. A white solid, Mp: 184e185 ꢁC. 1H NMR
(CDCl3, 300 MHz, TMS)
d
1.04 (t, J¼6.9 Hz, 3H, CH3), 3.98e4.14 (m,
d
1.10 (t, J¼7.2 Hz, 3H, CH3), 4.02e4.22 (m,
2H, CH2), 4.30 (d, J¼9.6 Hz, 1H, CH), 5.70 (d, J¼9.6 Hz, 1H, CH), 6.62
(s, 1H,]CH), 7.04e7.10 (m, 1H, Ar), 7.32e7.51 (m, 5H, Ar), 7.76e7.88
(m, 3H, Ar), 7.94 (d, J¼8.4 Hz, 2H, Ar), 8.02 (d, J¼7.5 Hz, 1H, Ar). 13C
2H, CH2), 4.23 (d, J¼9.0 Hz, 1H, CH), 5.66 (d, J¼9.0 Hz, 1H, CH), 6.62
(s, 1H,]CH), 7.27e7.29 (m, 2H, Ar), 7.36 (d, J¼8.4 Hz, 2H, Ar), 7.43
(d, J¼7.8 Hz,1H, Ar), 7.76e7.88 (m, 3H, Ar), 7.94 (d, J¼8.4 Hz, 2H, Ar),
NMR (CDCl3, 100 MHz, TMS)
d
13.7, 52.2, 60.8, 62.0, 71.7, 123.2,
8.02 (d, J¼7.2 Hz, 1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d 13.8,
123.7, 123.8, 125.0, 128.1, 128.3, 128.7, 130.4, 132.8, 136.4, 136.6,
49.0, 60.9, 61.6, 71.5, 123.3, 123.7, 123.8, 127.9, 128.9, 129.2, 130.1,
133.4, 134.7,136.5, 136.7, 137.9, 138.4, 141.6,142.0, 144.7,147.4, 162.6,
137.8, 141.0, 141.7, 142.3, 145.5, 147.3, 162.8, 197.7, 199.4. IR (CH2Cl2)
n
1235, 1268, 1322, 1346, 1521, 1706, 1744, 2972, 3040 cmꢀ1. MS (ESI)
197.5, 199.2. IR (CH2Cl2) n 742, 846, 1017, 1100, 1234, 1345, 1475,
m/e 546.0 (Mþþ1). HRMS (MALDI) calcd for C28H20NO6BrNa:
1519, 1588, 1702, 2853, 2963 cmꢀ1. MS (ESI) m/e 558.0 (MþþNa).

7918
F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
HRMS (MALDI) calcd for C28H19NO6Cl2Na: 558.0482. Found:
558.0477; Enantiomeric excess was determined by HPLC with
123.8, 128.1 (d, J¼7.1 Hz), 129.9, 136.6, 136.7, 138.4, 138.5 (d,
J¼3.7 Hz), 141.5, 141.7, 142.1, 144.3, 147.4, 158.3 (d, J¼246.1 Hz),
a
Chiralcel OD-H column
[
l
¼230 nm; eluent: Hexane/Iso-
162.8, 197.7, 199.1. 19F NMR (376 MHz, CFCl3)
d
ꢀ109.16e109.11 (m).
propanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼33.73 min,
IR (CH2Cl2) n 908, 1014, 1088, 1145, 1235, 1349, 1493, 1519, 1598,
tminor¼42.43 min; ee%¼96%; ½a D20
ꢃ
¼þ255.7 (c 1.0, CH2Cl2)].
1705, 2853, 2930 cmꢀ1. MS (ESI) m/e 586.0 (MþþNa). HRMS
(MALDI) calcd for C28H19NO6FBrNa: 586.0265. Found: 586.0272;
Enantiomeric excess was determined by HPLC with a Chiralcel OD-
3.2.15. Compound 3l. A white solid, Mp: 109e110 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
d
1.06 (t, J¼7.2 Hz, 3H, CH3), 3.98e4.13 (m,
H column [
rate: 0.50 mL/min; tmajor¼36.21 min, tminor¼54.41 min; ee%¼90%;
a 2D0
¼þ181.8 (c 1.0, CH2Cl2)].
l¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow
2H, CH2), 4.27 (d, J¼7.2 Hz, 1H, CH), 5.77 (d, J¼7.2 Hz, 1H, CH), 6.63
(s, 1H,]CH), 7.22e7.27 (m, 1H, Ar), 7.32e7.39 (m, 1H, Ar), 7.37 (d,
J¼8.4 Hz, 2H, Ar), 7.42 (d, J¼7.6 Hz, 1H, Ar), 7.76e7.81 (m, 2H, Ar),
7.83e7.87 (m, 1H, Ar), 7.94 (d, J¼8.4 Hz, 2H, Ar), 8.01 (d, J¼8.0 Hz,
½
ꢃ
3.2.19. Compound 3p. A white solid, Mp: 145e146 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d
13.7, 50.2, 60.9, 61.7, 71.6,
d
1.11 (t, J¼7.2 Hz, 3H, CH3), 4.02e4.16 (m,
123.3, 123.7, 123.8, 126.2, 127.7, 129.3, 130.1, 132.5, 133.2, 136.5,
136.7, 138.2, 141.6, 141.8, 142.1, 145.0, 147.4, 162.6, 197.5, 199.2. IR
2H, CH2), 4.09 (d, J¼10.4 Hz, 1H, CH), 5.10 (dd, J¼10.4 Hz, J¼2.0 Hz,
1H, CH), 6.68 (d, J¼2.0 Hz, 1H,]CH), 7.03e7.08 (m, 5H, Ar), 7.23 (d,
J¼8.8 Hz, 2H, Ar), 7.71e7.76 (m, 2H, Ar), 7.78e7.82 (m, 1H, Ar), 7.98
(d, J¼7.2 Hz, 1H, Ar), 8.11 (d, J¼8.8 Hz, 2H, Ar). 13C NMR (CDCl3,
(CH2Cl2)
n 848, 902, 1015, 1095, 1167, 1232, 1269, 1344, 1519, 1597,
1705, 1743, 2925, 2957 cmꢀ1. MS (ESI) m/e 535.9 (Mþþ1). HRMS
(MALDI) calcd for C28H19NO6Cl2Na: 558.0478. Found: 558.0482;
Enantiomeric excess was determined by HPLC with a Chiralcel OD-
100 MHz, TMS)
d 13.9, 53.8, 60.9, 62.9, 71.7, 123.4, 123.5, 123.8,
127.9,128.4,128.7,133.8,136.1,136.3,139.4,141.8,141.9,144.3,146.9,
H column [
l
¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow
149.6, 163.0, 198.0, 199.8. IR (CH2Cl2) n 842, 1016, 1106, 1166, 1233,
rate: 0.50 mL/min; tmajor¼34.78 min, tminor¼42.96 min; ee%¼98%;
1514, 1599, 1699, 1724, 2915, 2955 cmꢀ1. MS (ESI) m/e 468.0
(Mþþ1). HRMS (MALDI) calcd for C28H21NO6Na: 490.1244. Found:
490.1261; Enantiomeric excess was determined by HPLC with
a 20
½ ꢃD ¼þ198.8 (c 1.0, CH2Cl2)].
3.2.16. Compound 3m. A white solid, Mp: 199e200 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
a
Chiralcel OD-H column
[
l
¼230 nm; eluent: Hexane/Iso-
d
1.13 (t, J¼7.2 Hz, 3H, CH3), 4.07 (dq, J¼11.2,
propanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼43.13 min,
Hz J¼7.2 Hz,1H, CH2), 4.14 (dq, J¼11.2, Hz J¼7.2 Hz,1H, CH2), 4.19 (d,
J¼10.4 Hz, 1H, CH), 4.97 (dd, J¼10.4 Hz, J¼2.4 Hz, 1H, CH), 6.62 (d,
J¼2.4 Hz, 1H,]CH), 7.10 (dd, J¼8.4 Hz, J¼2.4 Hz, 1H, Ar), 7.31 (d,
J¼8.8 Hz, 2H, Ar), 7.32e7.35 (m, 2H, Ar), 7.75e7.82 (m, 2H, Ar),
7.84e7.88 (m, 1H, Ar), 7.97 (d, J¼8.8 Hz, 2H, Ar), 8.02 (d, J¼8.0 Hz,
tminor¼51.44 min; ee%¼66%; ½a D20
ꢃ ¼þ149.2 (c 1.0, CH2Cl2)].
3.2.20. Compound 3q. A white solid, Mp: 245e246 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
d
1.10 (t, J¼7.2 Hz, 3H, CH3), 4.04 (d,
J¼10.4 Hz, 1H, CH), 4.03e4.13 (m, 2H, CH2), 5.05 (dd, J¼10.4 Hz,
J¼2.0 Hz,1H, CH), 6.67 (d, J¼2.0 Hz,1H,]CH), 6.96e7.00 (m,1H, Ar),
7.08 (d, J¼8.0 Hz, 1H, Ar), 7.20 (d, J¼8.0 Hz, 1H, Ar), 7.21 (s, 1H, Ar),
7.41 (d, J¼8.4 Hz, 2H, Ar), 7.78e7.86 (m, 3H, Ar), 8.01 (d, J¼7.6 Hz,
1H, Ar), 8.13 (d, J¼8.4 Hz, 2H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
1H, Ar). 13C NMR (CDCl3, 100 MHz, TMS)
d 13.9, 53.5, 61.0, 61.2, 71.4,
123.6, 123.8, 126.9, 129.4, 129.9, 130.7, 131.4, 132.8, 136.6, 136.7,
138.6, 141.3, 141.5, 141.7, 142.0, 144.1, 147.4, 162.7, 197.6, 199.0. IR
(CH2Cl2) n 849, 1030, 1078, 1144, 1231, 1269, 1348, 1470, 1523, 1595,
1705, 1742, 2852, 2922 cmꢀ1. MS (ESI) m/e 535.9 (Mþþ1). HRMS
(MALDI) calcd for C28H19NO6Cl2Na: 558.0475. Found: 558.0482;
Enantiomeric excess was determined by HPLC with a Chiralcel OD-
d 13.9, 54.0, 60.9, 61.8, 71.6, 122.5, 123.6, 123.7, 123.9, 127.4, 128.4,
130.0, 131.1, 131.9, 136.3, 136.4, 136.5, 139.3, 141.7, 141.8, 144.0, 147.1,
149.1, 162.8, 197.7, 199.3. IR (CH2Cl2) n 1013, 1083, 1229, 1268, 1343,
H column [
rate: 0.50 mL/min; tmajor¼34.95 min, tminor¼51.14 min; ee%¼92%;
a 2D0
¼þ189.5 (c 1.0, CH2Cl2)].
l¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow
1512, 1594, 1704, 1743, 2852, 2922 cmꢀ1. MS (ESI) m/e 545.9
(Mþþ1). HRMS (MALDI) calcd for C28H20NO6BrNa: 568.0361.
Found: 568.0366; Enantiomeric excess was determined by HPLC
½
ꢃ
with a Chiralcel IC-H column [
l
¼230 nm; eluent: Hexane/Iso-
3.2.17. Compound 3n. A white solid, Mp: 122e123 ꢁC. 1H NMR
(CDCl3, 300 MHz, TMS)
propanol¼60/40; Flow rate: 0.40 mL/min; tmajor¼30.48 min,
d
1.07 (t, J¼7.2 Hz, 3H, CH3), 4.03e4.17 (m,
tminor¼53.03 min; ee%¼67%; ½a D20
ꢃ ¼þ150.6 (c 1.0, CH2Cl2)].
2H, CH2), 5.16 (d, J¼11.1 Hz, 1H, CH), 6.04 (dd, J¼11.1 Hz, J¼1.5 Hz,
1H, CH), 6.59 (d, J¼1.5 Hz, 1H,]CH), 7.04e7.09 (m, 1H, Ar), 7.22 (d,
J¼7.8 Hz, 2H, Ar), 7.48 (d, J¼8.4 Hz, 2H, Ar), 7.79e7.85 (m, 3H, Ar),
7.93 (d, J¼8.4 Hz, 2H, Ar), 7.99 (d, J¼7.2 Hz, 1H, Ar). 13C NMR (CDCl3,
3.2.21. Compound 3r. A white solid, Mp: 128e129 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
d
1.10 (t, J¼7.2 Hz, 3H, CH3), 4.05 (d,
J¼10.4 Hz, 1H, CH), 4.04e4.13 (m, 2H, CH2), 5.04 (dd, J¼10.4 Hz,
J¼1.6 Hz, 1H, CH), 6.66 (d, J¼1.6 Hz, 1H,]CH), 6.98 (d, J¼8.4 Hz, 2H,
Ar), 7.22 (d, J¼8.4 Hz, 2H, Ar), 7.39 (d, J¼8.4 Hz, 2H, Ar), 7.79e7.86
(m, 3H, Ar), 7.99 (d, J¼7.2 Hz, 1H, Ar), 8.13 (d, J¼8.4 Hz, 2H, Ar). 13C
75 MHz, TMS) d 13.8, 49.9, 56.6, 60.8, 71.5, 123.2, 123.6, 123.7, 128.6,
128.8, 130.0, 130.7, 134.0, 135.2, 136.3, 136.4, 136.5, 141.5, 141.9,
142.3, 144.8, 147.6, 163.2, 198.2, 199.1. IR (CH2Cl2)
n 847, 1017, 1100,
1169, 1236, 1346, 1518, 1588, 1701, 2923, 2963 cmꢀ1. MS (ESI) m/e
536.0 (Mþþ1). HRMS (MALDI) calcd for C28H19NaO6Cl2Na:
558.0484. Found: 558.0482; Enantiomeric excess was determined
NMR (CDCl3,100 MHz, TMS) d 13.9, 54.1, 61.0, 61.8, 71.4,122.0,123.6,
123.7, 123.9, 128.4,130.5, 131.7,133.0,136.4,136.5, 139.3, 141.7,141.8,
144.1, 147.0, 149.2, 162.8, 197.9, 199.5. IR (CH2Cl2)
n 848, 1237, 1269,
by HPLC with a Chiralcel OD-H column [
l¼230 nm; eluent: Hexane/
1325, 1347, 1523, 1707, 1744, 2973, 3041 cmꢀ1 MS (ESI) m/e 546.0
(Mþþ1). HRMS (MALDI) calcd for C28H20NO6BrNa: 568.0352.
Found: 568.0366; Enantiomeric excess was determined by HPLC
Isopropanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼47.54 min,
tminor¼55.01 min; ee%¼69%; ½a D20
ꢃ ¼þ145.3 (c 1.0, CH2Cl2)].
with a Chiralcel OD-H column [
l
¼230 nm; eluent: Hexane/Iso-
3.2.18. Compound 3o. A white solid, Mp: 223e224 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS)
propanol¼60/40; Flow rate: 0.50 mL/min; tmajor¼48.82 min,
d
1.12 (t, J¼7.2 Hz, 3H, CH3), 4.06 (dq,
tminor¼72.04 min; ee%¼65%; ½a D20
ꢃ ¼þ147.2 (c 1.0, CH2Cl2)].
J¼11.2 Hz, J¼7.2 Hz, 1H, CH), 4.14 (dq, J¼11.2 Hz, J¼7.2 Hz, 1H, CH),
4.19 (d, J¼10.0 Hz, 1H, CH), 4.97 (dd, J¼10.0 Hz, J¼2.8 Hz, 1H, CH),
6.60 (d, J¼2.8 Hz, 1H,]CH), 7.00e7.05 (m, 1H, Ar), 7.15e7.19 (m, 1H,
Ar), 7.31 (d, J¼9.2 Hz, 2H, Ar), 7.44 (dd, J¼6.8 Hz, J¼2.4 Hz, 1H, Ar),
7.75e7.82 (m, 2H, Ar), 7.84e7.88 (m, 1H, Ar), 7.97 (d, J¼9.2 Hz, 2H,
3.2.22. Compound 3s. A white solid, Mp: 168e169 ꢁC. 1H NMR
(CDCl3, 400 MHz, TMS) 0.37e0.46 (m, 1H, CH), 0.56e0.64 (m, 1H,
d
CH2), 0.83e0.89 (m, 3H, CH2), 1.05 (t, J¼7.2 Hz, 3H, CH3), 1.32e1.33
(m, 2H, CH2), 1.43e1.50 (m, 2H, CH2), 1.68e1.72 (m, 1H, CH2),
1.89e1.97 (m, 1H, CH), 3.10 (dd, J¼10.4 Hz, J¼8.4 Hz, 1H, CH),
3.90e4.46 (m, 2H, CH), 4.46 (dd, J¼8.4 Hz, J¼1.2 Hz,1H, CH), 6.38 (d,
Ar), 8.02 (d, J¼7.6 Hz,1H, Ar). 13C NMR (CDCl3,100 MHz, TMS)
d 13.9,
53.4, 61.0, 61.3, 71.4, 109.3 (d, J¼21.4 Hz), 116.4 (d, J¼22.4 Hz), 123.6,

F. Hu et al. / Tetrahedron 68 (2012) 7911e7919
7919
6035e6041; (d) Zheng, S.-Q.; Lu, X.-Y. Org. Lett. 2008, 10, 4481e4484; (e)
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Tang, Y. Angew. Chem., Int. Ed. 2007, 46, 5951e5954; (h) Han, X.; Ye, L.-W.;
Sun, X.-L.; Tang, Y. J. Org. Chem. 2009, 74, 3394e3397; (i) Zhou, R.; Wang, J.-F.;
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J¼1.2 Hz, 1H,]CH), 7.62 (d, J¼8.4 Hz, 2H, Ar), 7.93e7.96 (m, 2H, Ar),
8.04e8.10 (m, 2H, Ar), 8.20 (d, J¼8.4 Hz, 2H, Ar). 13C NMR (CDCl3,
100 MHz, TMS)
d 13.8, 25.5, 25.6, 32.4, 33.1, 39.0, 55.0, 60.2, 60.6,
70.4, 123.5, 123.7, 124.2, 129.7, 136.3, 139.0, 140.5, 141.2, 143.3, 146.6,
152.4, 162.8, 198.4, 199.7. IR (CH2Cl2) n 1105, 1142, 1160, 1233, 1342,
1509, 1593, 1701, 2842, 2933 cmꢀ1. MS (ESI) m/e 474.1 (Mþþ1).
HRMS (MALDI) calcd for C28H27NO6Na: 496.1729. Found: 496.1731;
Enantiomeric excess was determined by HPLC with a Chiralcel OD-
H column [
rate: 0.50 mL/min; tmajor¼31.90 min, tminor¼28.90 min; ee%¼67%;
a 2D0
¼ꢀ91.1 (c 1.0, CH2Cl2)].
l¼230 nm; eluent: Hexane/Isopropanol¼60/40; Flow
½
ꢃ
12. For reviews on chiral phosphorus compound as catalysts in organocatalytic
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Acknowledgements
We thank the Shanghai Municipal Committee of Science and
Technology (11JC1402600), National Basic Research Program of
China (973)-2010CB833302, the Fundamental Research Funds for
the Central Universities and the National Natural Science Founda-
tion of China for financial support (21072206, 20872162, 20672127,
20732008, 21121062, and 20702013).
13. For selected references of chiral multifunctional phosphines as organo-
catalysts: (a) Shi, M.; Chen, L.-H. Chem. Commun. 2003, 1310e1311; (b) Shi,
M.; Chen, L.-H.; Li, C.-Q. J. Am. Chem. Soc. 2005, 127, 3790e3800; (c) Matsui,
K.; Takizawa, S.; Sasai, H. Synlett 2006, 761e765; (d) Shi, M.; Ma, G.-N.; Gao, J.
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2008, 350, 122e128; (f) Garnier, J.-M.; Anstiss, C.; Liu, F. Adv. Synth. Catal.
2009, 351, 331e338; (g) Anstiss, C.; Garnier, J.-M.; Liu, F. Org. Biomol. Chem.
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2009, 20, 1086e1092; (m) Xiao, H.; Chai, Z.; Zheng, C.-W.; Yang, Y.-Q.; Liu, W.;
Zhang, J.-K.; Zhao, G. Angew. Chem., Int. Ed. 2010, 49, 4467e4470; (n) Han, X.-
Y.; Wang, Y.-Q.; Zhong, F.-R.; Lu, Y.-X. J. Am. Chem. Soc. 2011, 133, 1726e1729;
(o) Zhong, F.-R.; Wang, Y.-Q.; Han, X.-Y.; Huang, K.-W.; Lu, Y.-X. Org. Lett.
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mun. 2011, 1491e1493; (s) Song, H.-L.; Yuan, K.; Wu, X.-Y. Chem. Commun.
2011, 1012e1014.
Supplementary data
Detailed description of experimental procedures, spectral
charts, and analytical data for new compounds shown in schemes
and figures, CIF files, and X-ray crystal data of 3k (CCDC 872832).
This material is available free of charge from authors or via the
internet. Supplementary data associated with this article can be
found, in the online version, at http://dx.doi.org/10.1016/
j.tet.2012.07.013.
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