新型CBS凝胶催化剂的合成及催化性能
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摘要
1,1-二苯基-1-[(2S,4R)-4-(4-乙烯基-苄氧基)-2-吡咯烷基]-甲醇(功能单体4)、苯乙烯与聚醚Pluronic F-127在过氧化月桂酰引发下进行溶液聚合,得到独特的梳状接枝共聚物。接枝共聚物进一步反应,形成交联的CBS催化剂前体(G-CBSP)。前体与甲基硼酸在甲苯-四氢呋喃中进行缩合反应,得到新型CBS凝胶催化剂(GCBS),用于催化苯乙酮的不对称还原反应。通过FTIR对催化剂结构进行表征,利用SEM观察反应介质中聚醚Pluronic F-127组分对催化剂凝胶形态的影响,考察G-CBS的催化效果及循环使用情况,比较了其与聚苯乙烯负载的CBS催化剂的催化性能。结果表明:聚醚Pluronic F-127片段的引入对G-CBS具有增溶效应,强化了催化剂与反应体系的相容性,有效解决了高交联度负载型催化剂选择性下降的问题。使用该催化剂还原产物苯乙醇ee值达94%,接近CBS均相催化反应的性能,优于目前报道的异相负载体系。催化剂循环使用5次,苯乙醇ee值仍可达到90%以上,苯乙酮转化率接近100%。
1,1-Diphenyl-1-[(2S,4R)-4-(4-vinyl-benzyloxy)-pyrrolidin-2-yl]-methanol(monomer4),styrene and polyethe r Pluronic F-127 were initiated by lauroyl peroxide for solution polymerization, toobtain a unique comb graft-copolymer, which was further reacted to form the gel crosslinked CBS catalystprecursor(G-CBSP). The novel CBS gel catalyst(G-CBS) was then prepared by condensation reaction ofthe G-CBSP with methylboronic acid in toluene-tetrahydrofuran and subsequently used for the asymmetric reduction of acetophenone. The structure of the catalyst was characterized by FTIR. The influence of the polyether Pluronic F-127 component on the gel morphology of the catalyst was observedby SEM. Besides, the catalytic performance and the recyclability of catalyst were investigated. The G-CBS catalyst was compared with the polystyrene supported CBS catalyst. The results showed that the introduction of polyethe r Pluronic F-127 component had a solubilizing effect on G-CBS which enhancedthe compatibility between the catalyst and the reaction system, which effectively solved the problem of the selective reduction of the highly crosslinked supported catalyst. With the catalyst, the ee value of the reduced product phenylethanol was 94%, which was close to the performance of homogeneous system andbetter than the currently reported catalysts in heterogeneous system. After the catalyst was recycled for 5
times,theee value of phenylethanol can still reach 90%,and the conversion of acetophenone approached 100%.
1,1-Diphenyl-1-[(2S,4R)-4-(4-vinyl-benzyloxy)-pyrrolidin-2-yl]-methanol(monomer4),styrene and polyethe r Pluronic F-127 were initiated by lauroyl peroxide for solution polymerization, toobtain a unique comb graft-copolymer, which was further reacted to form the gel crosslinked CBS catalystprecursor(G-CBSP). The novel CBS gel catalyst(G-CBS) was then prepared by condensation reaction ofthe G-CBSP with methylboronic acid in toluene-tetrahydrofuran and subsequently used for the asymmetric reduction of acetophenone. The structure of the catalyst was characterized by FTIR. The influence of the polyether Pluronic F-127 component on the gel morphology of the catalyst was observedby SEM. Besides, the catalytic performance and the recyclability of catalyst were investigated. The G-CBS catalyst was compared with the polystyrene supported CBS catalyst. The results showed that the introduction of polyethe r Pluronic F-127 component had a solubilizing effect on G-CBS which enhancedthe compatibility between the catalyst and the reaction system, which effectively solved the problem of the selective reduction of the highly crosslinked supported catalyst. With the catalyst, the ee value of the reduced product phenylethanol was 94%, which was close to the performance of homogeneous system andbetter than the currently reported catalysts in heterogeneous system. After the catalyst was recycled for 5
times,theee value of phenylethanol can still reach 90%,and the conversion of acetophenone approached 100%.
引文
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[4]王广印.高分子负载手性配体催化的不对称还原反应研究及其在有机合成中的应用[D].上海:中国科学院上海有机化学研究所,2006.WANG G Y. Asymmetric reduction catalyzed by polymer loaded chiralligands and their applications in organic synthesis[D]. Shanghai:Shanghai Institute of Organic Chemistry, Chinese Academy ofSciences, 2006.
[5] GIFFELS G, BELICZEY J, FELDER M, et al. Polymer enlargedoxazaborolidines in a membrane reactor:enhancing effectivity byretention of the homogeneous catalyst[J]. Tetrahedron Asymmetry,1998, 9(4):691-696.
[6] ITSUNO S, HIRAO A, NAKAHAMA S, et al. Asymmetric reduction ofaromatic ketones with(S)-2-boryloxymethyl-1-pyrrolidinylsubstituted polystyrene gel[J]. Makromol. Chem. Rapid Commun.,1982, 3(10):673-676.
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[8] DAI S X, LI G H, ZHANG W B, et al. Efficient synthesis of(R)-phenylephrine using a polymer-supported Corey-Bakshi-Shibatacatalyst[J]. Chemistry Letters, 2017, 46(5):740-743.
[9] DEGNI S, WILéN C E, ROSLING A. Highly catalytic enantioselectivereduction of aromatic ketones using chiral polymer-supported Corey,Bakshi, and Shibata catalysts[J]. Tetrahedron:Asymmetry, 2004, 15(9):1495-1499.
[10] DEGNI S, WILéN C E, LEINO R. Asymmetric C—C bond formationwith l-prolinol derived chiral catalysts immobilized on polymer fibers[J]. Tetrahedron Asymmetry, 2004, 15(2):231-237.
[11] DEGNI S, WILéN C E, LEINO R. Immobilization of chiral ligands onpolymer fibers by electron beam induced grafting and applications inenantioselective catalysis[J]. Organic Letters, 2001, 3(16):2551-2554.
[12] W?LTINGER J, BOMMARIUS A S, DRAUZ K, et al. The chemzymemembrane reactor in the fine chemicals industry[J]. Organic ProcessResearch&Development, 2001, 5(3):241-248.
[13] W?LTINGER J, DRAUZ K, BOMMARIUS A S. The membranereactor in the fine chemicals industry[J]. Applied Catalysis A:General,2001, 221(1):171-185.
[14]郑玉婴,江琳沁,赵剑曦,等. Pluronic嵌段共聚物F127和P123胶束对萘、蒽、芘的增溶[J].高等学校化学学报, 2001, 22(4):617-621.ZHENG Y Y, JIANG L Q, ZHAO J X, et al. Solubilization ofpolycyclic aromatic hydrocarbons in F127 and P123 aqueous micellarsolutions[J]. Chemical Journal of Chinese Universities, 2001, 22(4):617-621.
[15]苏延磊,郭晨,刘会洲. PEO-PPO-PEO嵌段共聚物胶团化及其应用研究进展[J].化工学报, 2003, 54(4):489-496.SU Y L, GUO C, LIU H Z. Review on micellization of PEO-PPO-PEOblock copolymer in aqueous solution and its applications[J]. Journal ofChemical Industry and Engineering, 2003, 54(4):489-496.
[16] BROMBERG L E. Novel family of thermogelling materials via C—Cbonding between poly(acrylic acid)and poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)[J]. Journal of PhysicalChemistry B, 1998, 102(11):1956-1963.
[17] BROMBERG L E, TEMCHENKO M, ALAKHOV V, et al. Bioadhesiveproperties and rheology of polyether-modified poly(acrylic acid)hydrogels[J]. International Journal of Pharmaceutics, 2004, 282(1):45-60.
[18] BROMBERG L E, RON E S. Temperature-responsive gels andthermogelling polymer matrices for protein and peptide delivery[J].Advanced Drug Delivery Reviews, 1998, 31(3):197-221.
[19] ZHANG Y, LAM Y M. Controlled synthesis and association behaviorof graft Pluronic in aqueous solutions[J]. Journal of Colloid&InterfaceScience, 2007, 306(2):398-404.
[20] ZHANG Y, LAM Y M. Poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-g-poly(vinyl pyrrolidone):synthesis andcharacterization[J]. Journal of Colloid&Interface Science, 2005, 285(1):80-85.
[21]赵剑曦. Pluronic嵌段共聚物胶束化行为及其胶束增溶[J].精细化工, 2001, 18(12):720-730.ZHAO J X. Micellization of Pluronic block copolymers in aqueoussolution and solubilizationof hydrophobic compounds in the micellarsolutions[J]. Fine Chemicals, 2001, 18(12):720-730.
[22]雍有,朱晶莹,卢滇楠,等.有机相温敏性脂肪酶催化剂的结构和催化特性[J].化工学报, 2015, 66(7):2534-2539.YONG Y, ZHU J Y, LU D N, et al. Structural and catalyticcharacteristics of temperature-responsive lipase catalyst in organicsolvents[J]. CIESC Journal, 2015, 66(7):2534-2539.
[2] COREY E J, SHIBATA S, BAKSHI R K. An efficient and catalyticallyenantioselective route to(S)-(-)-phenyloxirane[J]. J. Org. Chem.,1988, 53(12):2861-2863.
[3] COREY E J,HELAL C J. Reduction of carbonyl compounds withchiral oxazaborolidine catalysts:a new paradigm for enantioselectivecatalysis and a powerful new synthetic method[J]. Angew. Chem. Int.Ed., 1998,37(15):1986-2012.
[4]王广印.高分子负载手性配体催化的不对称还原反应研究及其在有机合成中的应用[D].上海:中国科学院上海有机化学研究所,2006.WANG G Y. Asymmetric reduction catalyzed by polymer loaded chiralligands and their applications in organic synthesis[D]. Shanghai:Shanghai Institute of Organic Chemistry, Chinese Academy ofSciences, 2006.
[5] GIFFELS G, BELICZEY J, FELDER M, et al. Polymer enlargedoxazaborolidines in a membrane reactor:enhancing effectivity byretention of the homogeneous catalyst[J]. Tetrahedron Asymmetry,1998, 9(4):691-696.
[6] ITSUNO S, HIRAO A, NAKAHAMA S, et al. Asymmetric reduction ofaromatic ketones with(S)-2-boryloxymethyl-1-pyrrolidinylsubstituted polystyrene gel[J]. Makromol. Chem. Rapid Commun.,1982, 3(10):673-676.
[7] ITSUNO S, ITO K, HIRAO A, et al. Asymmetric synthesis usingchirally modified borohydrides. Part 2. Enantioselective reduction ofketones with polymeric(S)-prolinol-borane reagent[J]. J. Chem. Soc.Perkin Trans. I., 1984:2887-2893.
[8] DAI S X, LI G H, ZHANG W B, et al. Efficient synthesis of(R)-phenylephrine using a polymer-supported Corey-Bakshi-Shibatacatalyst[J]. Chemistry Letters, 2017, 46(5):740-743.
[9] DEGNI S, WILéN C E, ROSLING A. Highly catalytic enantioselectivereduction of aromatic ketones using chiral polymer-supported Corey,Bakshi, and Shibata catalysts[J]. Tetrahedron:Asymmetry, 2004, 15(9):1495-1499.
[10] DEGNI S, WILéN C E, LEINO R. Asymmetric C—C bond formationwith l-prolinol derived chiral catalysts immobilized on polymer fibers[J]. Tetrahedron Asymmetry, 2004, 15(2):231-237.
[11] DEGNI S, WILéN C E, LEINO R. Immobilization of chiral ligands onpolymer fibers by electron beam induced grafting and applications inenantioselective catalysis[J]. Organic Letters, 2001, 3(16):2551-2554.
[12] W?LTINGER J, BOMMARIUS A S, DRAUZ K, et al. The chemzymemembrane reactor in the fine chemicals industry[J]. Organic ProcessResearch&Development, 2001, 5(3):241-248.
[13] W?LTINGER J, DRAUZ K, BOMMARIUS A S. The membranereactor in the fine chemicals industry[J]. Applied Catalysis A:General,2001, 221(1):171-185.
[14]郑玉婴,江琳沁,赵剑曦,等. Pluronic嵌段共聚物F127和P123胶束对萘、蒽、芘的增溶[J].高等学校化学学报, 2001, 22(4):617-621.ZHENG Y Y, JIANG L Q, ZHAO J X, et al. Solubilization ofpolycyclic aromatic hydrocarbons in F127 and P123 aqueous micellarsolutions[J]. Chemical Journal of Chinese Universities, 2001, 22(4):617-621.
[15]苏延磊,郭晨,刘会洲. PEO-PPO-PEO嵌段共聚物胶团化及其应用研究进展[J].化工学报, 2003, 54(4):489-496.SU Y L, GUO C, LIU H Z. Review on micellization of PEO-PPO-PEOblock copolymer in aqueous solution and its applications[J]. Journal ofChemical Industry and Engineering, 2003, 54(4):489-496.
[16] BROMBERG L E. Novel family of thermogelling materials via C—Cbonding between poly(acrylic acid)and poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)[J]. Journal of PhysicalChemistry B, 1998, 102(11):1956-1963.
[17] BROMBERG L E, TEMCHENKO M, ALAKHOV V, et al. Bioadhesiveproperties and rheology of polyether-modified poly(acrylic acid)hydrogels[J]. International Journal of Pharmaceutics, 2004, 282(1):45-60.
[18] BROMBERG L E, RON E S. Temperature-responsive gels andthermogelling polymer matrices for protein and peptide delivery[J].Advanced Drug Delivery Reviews, 1998, 31(3):197-221.
[19] ZHANG Y, LAM Y M. Controlled synthesis and association behaviorof graft Pluronic in aqueous solutions[J]. Journal of Colloid&InterfaceScience, 2007, 306(2):398-404.
[20] ZHANG Y, LAM Y M. Poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-g-poly(vinyl pyrrolidone):synthesis andcharacterization[J]. Journal of Colloid&Interface Science, 2005, 285(1):80-85.
[21]赵剑曦. Pluronic嵌段共聚物胶束化行为及其胶束增溶[J].精细化工, 2001, 18(12):720-730.ZHAO J X. Micellization of Pluronic block copolymers in aqueoussolution and solubilizationof hydrophobic compounds in the micellarsolutions[J]. Fine Chemicals, 2001, 18(12):720-730.
[22]雍有,朱晶莹,卢滇楠,等.有机相温敏性脂肪酶催化剂的结构和催化特性[J].化工学报, 2015, 66(7):2534-2539.YONG Y, ZHU J Y, LU D N, et al. Structural and catalyticcharacteristics of temperature-responsive lipase catalyst in organicsolvents[J]. CIESC Journal, 2015, 66(7):2534-2539.