J. Huang et al. / Tetrahedron 69 (2013) 5460e5467
5461
supplied by Alfa Aesar. Other commercially available chemicals were
laboratory-grade reagents from local suppliers. Chiral salen ligand
and chiral homogeneous catalyst salen Mn(III) were synthesized
according to the standard literature procedures,19 and further iden-
tified by analysis and comparison of IR spectra with literature.20
FT-IR spectra were recorded from KBr pellets using a Bruker
RFS100/S spectrophotometer (USA) and diffuse reflectance UVevis
spectra of the solid samples were recorded in the spectrophotometer
2 (0.5 mmol) was added equal equimolar of NaN3 at room tem-
perature. After the reaction mixture was refluxed at 50 ꢁC for 10 h,
the azide 3, 3-bromoprop-1-yne (1.8 mL, 23 mmol), sodium
ascorbate (0.2 equiv), and copper (II) sulfate pentahydrate
(0.1 equiv) were added in THF/H2O successively. 2 h later, strong
aqua were added to the system and the brown solid 4 was obtained
through filtration and washing. IR (KBr): vmax/cmꢀ1 3025, 2926
(CH), 2920, 2851 (triazole), 2342 (O]PeOH), 1651, 1543, 1511, 1492
(eC6H5), 1261 (P]O), 699 (CeBr) cmꢀ1. Found: C, 42.61; H, 3.18; N,
10.62%. Calcd for C104H105N24O11P3Br8Na2Zn3: C, 43.96; H, 3.70; N,
11.84%.
with an integrating sphere using BaSO4 as standard. 1H NMR and 31
P
NMR were performed on AV-300 NMR instrument at ambient tem-
perature at 300 and 121 MHz, respectively. All of the chemical shifts
were reported downfield inparts per million relative to the hydrogen
and phosphorus resonance of TMS and 85% H3PO4, respectively.
Number- and weight-average molecular weights (Mn and Mw) and
polydispersity (Mw/Mn) were estimated by Waters1515 gel perme-
ation chromatograph (GPC; against polystyrene standards) using
THF as an eluent (1.0 mL minꢀ1) at 35 ꢁC. X-ray photoelectron
spectrum was recorded on ESCALab250 instrument. The interlayer
spacings were obtained on DX-1000 automated X-ray power dif-
2.2.5. Synthesis of aminomethyl-triazole-zinc poly(styrenephenyl-
vinylphosphonate)-phosphate (ZnTAMPS-PVPA). Proper amount of
diamines (such as a: 1,2-ethylenediamine, b: 1,3-propanediamine,
c: 1,4-butanediamine, d: 1,6-hexylenediamine) were mixed with
ZnTPS-PVPA (2.68 g), Na2CO3 (4.24 g, 0.04 mol), and THF (10 mL).
After the mixture was kept at 66 ꢁC for 10 h, the resinlike product
was filtered, washed, and dried in vacuo. The products were ab-
breviated as 5a, 5b, 5c, and 5d in turn. Compound 5a, Found: C,
52.15; H, 5.82; N, 19.46%. Calcd for C120H161N40O11P3Na2Zn3: C,
53.91; H, 6.03; N, 20.97%. Compound 5b, Found: C, 54.26; H, 6.04; N,
19.28%. Calcd for C128H177N40O11P3Na2Zn3: C, 55.19; H, 6.36; N,
20.12%. Compound 5c, Found: C, 55.26; H, 6.15; N, 19.06%. Calcd for
C136H193N40O11P3Na2Zn3: C, 56.37; H, 6.67; N, 19.34%. Compound
5d, Found: C, 57.12; H, 7.08; N, 16.51%. Calcd for
C152H225N40O11P3Na2Zn3: C, 58.48; H, 7.21; N, 17.95%.
fractometer, using Cu Ka radiation and internal silicon powder
standard with all samples. The patterns were generally measured
between 3.00ꢁ and 80.00ꢁ with a step size of 0.02ꢁ minꢀ1 and X-ray
tube settings of 36 kV and 20 mA. C, H, and N elemental analysis was
obtained from an EATM 1112 automatic elemental analyzer in-
strument (Thermo, USA). TG analyses were performed on an
SBTQ600 thermal analyzer (USA) with the heating rate of
20 ꢁC minꢀ1 from 25 to 1000 ꢁC under flowing N2 (100 mL minꢀ1).
The Mn contents of the catalysts were determined by a TAS-986G
(Pgeneral, China) atomic absorption spectroscopy. SEM were per-
formed on KYKY-EM 3200 (KYKY, China) micrograph. TEM were
obtained on a TECNAI10 (PHILIPS, Holland) apparatus. Nitrogen ad-
sorption isotherms were measured at 77 K on a 3H-2000I (Huihai-
hong, China) volumetric adsorption analyzer with BET method. The
racemic epoxides were prepared by epoxidation of the correspond-
ing olefins by 3-chloroperbenzoic acid in CH2Cl2 and confirmed by
NMR (Bruker AV-300), and the gas chromatography (GC) was cali-
brated with the samples of n-nonane, olefins, and corresponding
racemic epoxides. The conversions (with n-nonane as internal
standard) and the ee values were analyzed by gas chromatography
(GC) with a Shimadzu GC2010 (Japan) instrument equipped using
2.3. Synthesis of grafting chiral salen Mn(III) catalyst onto
ZnTPS-PVPA (Scheme 2)
Chiral salen Mn(III) (4 mmol) in 10 mL of THF was added to the
solution of 5 (0.5 g) and Et3N (5 mmol). After the mixture was
refluxed for 10 h, the solution was neutralized and the solvent was
evaporated. The dark brown powder was obtained by filtration and
washing. The products were abbreviated as 6a, 6b, 6c, and 6d in
turn. Compound 6a, Found: C, 64.12; H, 7.08; N, 9.54%. Calcd for
C408H569N56O27P3Na2Zn3Mn8: C, 65.67; H, 7.63; N, 10.52%. Com-
pound 6b, Found: C, 64.15; H, 7.18; N, 9.24%. Calcd for
C416H585N56O27P3Na2Zn3Mn8: C, 65.97; H, 7.73; N, 10.36%. Com-
pound 6c, Found: C, 65.27; H, 7.61; N, 9.85%. Calcd for
C424H601N56O27P3Na2Zn3Mn8: C, 66.26; H, 7.83; N, 10.21%. Com-
pound 6d, Found: C, 65.27; H, 7.16; N, 9.23%. Calcd for
C440H633N56O27P3Na2Zn3Mn8: C, 66.81; H, 8.01; N, 9.92%.
a chiral column (HP19091G-B213, 30 mꢂ30 mꢂ0.32 mmꢂ0.25
mm)
and FID detector, injector 230 ꢁC, detector 230 ꢁC. Ultrapure nitrogen
was used as the carrier (rate 34 mL minꢀ1) with carrier pressure
39.1 kPa and the injection pore temperature was set at 230 ꢁC. The
column temperature for indene, a-methylstyrene and styrene was
programmed in the range of 80e180 ꢁC.
2.4. Synthesis of the homogeneous catalyst 10 (Scheme 3)
2.2. Synthesis of the support (Scheme 1)
To a solution of benzyl bromide (4 mmol) was added equal
equimolar of NaN3 at room temperature. After refluxing at 60 ꢁC for
10 h, the azide 7, 3-bromoprop-1-yne (0.9 mL, 11.5 mmol), sodium
ascorbate (0.2 equiv), and copper (II) sulfate pentahydrate
(0.1 equiv) were added in acetone/H2O successively. Then, 1,6-
hexylenediamine (20 mmol), Na2CO3 (0.848 g, 8 mmol) were
mixed with the compound 8 at 70 ꢁC for 6 h to gain the compound
9. The homogeneous catalyst 10 was synthesized according to the
2.2.1. Synthesis of styrene-phenylvinylphosphonic acid copolymer
(PS-PVPA). PS-PVPA was synthesized according to the literature.21
2.2.2. Synthesis of zinc poly(styrene-phenylvinylphosphonate)-
phosphate (ZnPS-PVPA). PS-PVPA (1.0 g, 1 mmol ), sodium dihy-
drogen phosphate (0.62 g, 4 mmol ), zinc acetate (1.1 g, 5 mmol),
and Et3N (0.68 g, 6.7 mmol ) were used for the synthesis of ZnPS-
PVPA according to the literature.22
similar procedure to the supported catalyst 6d. IR (KBr): vmax
/
cmꢀ1 3410, 1620 (eNHe), 3024, 2927 (CH), 2921, 2853 (triazole),
2339 (O]PeOH), 1651, 1543, 1513, 1492 (eC6H5), 1639 (eC]
N) cmꢀ1, 1262 (P]O). Compound 10, Found: C, 65.37; H, 8.12; N,
10.21%. Calcd for C51H74N7O2Mn: C, 66.81; H, 8.50; N, 11.25%.
2.2.3. Synthesis of chloromethyl-zinc poly(styrene-phenylvinylpho-
sphonate)-phosphate (ZnCMPS-PVPA). Chloromethyl methyl ether
(9.3 mL), anhydrous zinc chloride (3.32 g, 24.34 mmol), and ZnPS-
PVPA (5.0 g, 3.4 mmol) were applied in the preparation of
ZnCMPS-PVPA in compliance with the article.22
2.5. Asymmetric epoxidation
2.5.1. Using m-CPBA as oxidant. For m-CPBA/NMO system, the ac-
tivities of the catalysts were tested for the epoxidation of unfunc-
tionalized olefins in CH2Cl2 at ꢀ40 ꢁC for 5 h with alkene (1 mmol),
2.2.4. Synthesis of triazole modified zinc poly(styrene-
phenylvinylphosphonate)-phosphate (ZnTPS-PVPA). To a solution of