含有中心手性联烯的不对称合成及钯催化的联烯参与的串联环化反应研究
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摘要
联烯是一类含有1,2-丙二烯官能团的化合物,具有较高的反应活性。在过去的几十年间,人们对联烯化学的研究取得了不少的进展。此外联烯广泛存在于天然产物及药物分子中,其反应也已经被成功应用于天然产物、药物及材料的合成中。我的博士论文主要是在本课题组研究的基础上,研究了含有中心手性联烯化合物的不对称合成及官能团化联烯的串联反应,并对既含有中心手性也含有轴手性的官能团化联烯的合成进行了初探。
本文主要包括以下两个部分：
第一部分：含有中心手性联烯的不对称合成研究
1、含有中心手性的2,3-联烯基丙二酸二乙酯的不对称合成
我们以2,3-联烯基醋酸酯为原料,丙二酸二乙酯为亲核试剂,碳酸钾做碱,在钯/(R or S)-DTBM-segphos催化下以71-84%的产率和92-96%ee得到对应的手性2,3-联烯基丙二酸二乙酯。在反应中加入1当量的水对反应的产率有较大的提高。扫描电镜对碳酸钾颗粒大小的分析显示,水的加入使碳酸钾的颗粒变得更小,从而增加了反应速度。
当在联烯的末端引入一个取代基时,通过此方法便可得到同时含有轴手性和中心手性的联烯产物。条件优化后可以得到dr值为3.2/1的非对映异构体,其中一对对映异构体的ee值为98%,但两个非对映异构体不能通过柱层析分开。
2、含有中心手性的2,3-联烯基胺的不对称合成
我们以2,3-联烯基磷酸酯为原料,TsNHR为亲核试剂,在钯/R or S)-3,4,5-(MeO)3-MeOBIPHEP催化下以47-90%的产率和88-94%ee得到对应的手性2,3-联烯基胺。其中R基团可以为2,3-联烯基,炔丙基及烯丙基等多种在合成中非常有用的官能团,生成含有中心手性的联烯-联烯、联烯-炔、联烯-烯等产物。
第二部分：零价钯催化的串联加成环化反应研究
醋酸钯催化下,2,3-联烯醇或2,3-联烯基丙二酸酯与邻碘苯甲醛或其亚胺在乙腈中80℃反应可以高产率、高立体选择性的得到氧桥或氮桥苯并七元环化合物。当以光学活性的2,3-联烯醇与邻碘苯甲醛反应时,我们可以得到同时含有三个手性中心的多环产物,且没有观察到消旋化现象。
Allenes are a class of compounds containing a unique1,2-propadiene structural unit with high reactivity. Great efforts have been made on the allene chemistry in the past few decades. In addition, allenes widely exist in natural products and pharmaceutical molecules. The reactions of allenes have been applied as the key steps in the synthesis of some natural products, pharmaceuticals, and materials. Based on the previous observations in our group, my attention has been focused on the asymmetric synthesis of chiral allenes bearing with a central chirality or a center and an axial chirality and the palladium-catalyzed cascade reactions of such allenes.
This dissertation includes two parts:
Part1:The asymmetric synthesis of allenes bearing with a central chirality
1. The asymmetric synthesis of2,3-allenyl malonates
With2,3-allenol acetates as the starting materials, diethyl malonate as the pronucleophile, and K2CO3as the base, chiral2,3-allenyl malonates could be obtained in71-84%yield and92-96%ee under the catalysis of [Pd(π-cinnamyl)Cl]2/(R or S)-DTBM-segphos. One equivalent of water has been proved to be crucial to ensure a high-yielding reaction. The SEM study shows that the size of K2CO3with1equiv of water is much smaller than that without water.
Allenes with both axial and central chirality could be obtained with3.2/1dr value under the optimized conditions when R group was introduced to the terminal position of the allene chain. But the diastereoisomers could not be separated by chromatography even though one of the enantiomer has a high ee value (98%ee).
2. The asymmetric synthesis of2,3-allenyl amines
With2,3-allenol phosphates as the starting materials, TsNHR as the nucleophiles, and DBU as the base, chiral2,3-allenyl amines could be obtained in47-90%yields and88-94%ee under the catalysis of [Pd(π-allyl)Cl]2/(R or S)-3,4,5-(MeO)3-MeOBIPHEP. The R group could also be2,3-allenyl, allyl, and alkynyl, which makes the products to be important starting materials in organic synthesis.
Part2:Palladium-catalyed cascade reactions of allenes
A Pd(OAc)2-catalyzed reaction of2,3-allenyl malonates or2,3-allenols with o-iodobenzaldehyde or its N-tosyl imine occurred smoothly in MeCN at80℃to form the oxa-or aza-bridged benzo[a,d]cycloheptane derivatives with important biological potentials. With the optically active2,3-allenols and the absolute configurations of all the three chiral centers could be conveniently established.
本文主要包括以下两个部分：
第一部分：含有中心手性联烯的不对称合成研究
1、含有中心手性的2,3-联烯基丙二酸二乙酯的不对称合成
我们以2,3-联烯基醋酸酯为原料,丙二酸二乙酯为亲核试剂,碳酸钾做碱,在钯/(R or S)-DTBM-segphos催化下以71-84%的产率和92-96%ee得到对应的手性2,3-联烯基丙二酸二乙酯。在反应中加入1当量的水对反应的产率有较大的提高。扫描电镜对碳酸钾颗粒大小的分析显示,水的加入使碳酸钾的颗粒变得更小,从而增加了反应速度。
当在联烯的末端引入一个取代基时,通过此方法便可得到同时含有轴手性和中心手性的联烯产物。条件优化后可以得到dr值为3.2/1的非对映异构体,其中一对对映异构体的ee值为98%,但两个非对映异构体不能通过柱层析分开。
2、含有中心手性的2,3-联烯基胺的不对称合成
我们以2,3-联烯基磷酸酯为原料,TsNHR为亲核试剂,在钯/R or S)-3,4,5-(MeO)3-MeOBIPHEP催化下以47-90%的产率和88-94%ee得到对应的手性2,3-联烯基胺。其中R基团可以为2,3-联烯基,炔丙基及烯丙基等多种在合成中非常有用的官能团,生成含有中心手性的联烯-联烯、联烯-炔、联烯-烯等产物。
第二部分：零价钯催化的串联加成环化反应研究
醋酸钯催化下,2,3-联烯醇或2,3-联烯基丙二酸酯与邻碘苯甲醛或其亚胺在乙腈中80℃反应可以高产率、高立体选择性的得到氧桥或氮桥苯并七元环化合物。当以光学活性的2,3-联烯醇与邻碘苯甲醛反应时,我们可以得到同时含有三个手性中心的多环产物,且没有观察到消旋化现象。
Allenes are a class of compounds containing a unique1,2-propadiene structural unit with high reactivity. Great efforts have been made on the allene chemistry in the past few decades. In addition, allenes widely exist in natural products and pharmaceutical molecules. The reactions of allenes have been applied as the key steps in the synthesis of some natural products, pharmaceuticals, and materials. Based on the previous observations in our group, my attention has been focused on the asymmetric synthesis of chiral allenes bearing with a central chirality or a center and an axial chirality and the palladium-catalyzed cascade reactions of such allenes.
This dissertation includes two parts:
Part1:The asymmetric synthesis of allenes bearing with a central chirality
1. The asymmetric synthesis of2,3-allenyl malonates
With2,3-allenol acetates as the starting materials, diethyl malonate as the pronucleophile, and K2CO3as the base, chiral2,3-allenyl malonates could be obtained in71-84%yield and92-96%ee under the catalysis of [Pd(π-cinnamyl)Cl]2/(R or S)-DTBM-segphos. One equivalent of water has been proved to be crucial to ensure a high-yielding reaction. The SEM study shows that the size of K2CO3with1equiv of water is much smaller than that without water.
Allenes with both axial and central chirality could be obtained with3.2/1dr value under the optimized conditions when R group was introduced to the terminal position of the allene chain. But the diastereoisomers could not be separated by chromatography even though one of the enantiomer has a high ee value (98%ee).
2. The asymmetric synthesis of2,3-allenyl amines
With2,3-allenol phosphates as the starting materials, TsNHR as the nucleophiles, and DBU as the base, chiral2,3-allenyl amines could be obtained in47-90%yields and88-94%ee under the catalysis of [Pd(π-allyl)Cl]2/(R or S)-3,4,5-(MeO)3-MeOBIPHEP. The R group could also be2,3-allenyl, allyl, and alkynyl, which makes the products to be important starting materials in organic synthesis.
Part2:Palladium-catalyed cascade reactions of allenes
A Pd(OAc)2-catalyzed reaction of2,3-allenyl malonates or2,3-allenols with o-iodobenzaldehyde or its N-tosyl imine occurred smoothly in MeCN at80℃to form the oxa-or aza-bridged benzo[a,d]cycloheptane derivatives with important biological potentials. With the optically active2,3-allenols and the absolute configurations of all the three chiral centers could be conveniently established.
引文
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32 Crystal data for compound (S,E)-31:C30H37N5O6S, MW=595.71, monoclinic, space group P 21, final R indices [I>2σ(I)], R1=0.0692, wR2=0.1882; R indices (all data), R1=0.0950, wR2=0.2221; a=9.9096(7) A, b=10.1964(7) A, c= 15.3893(12) A, a=90.00°,β=90.267(6)°,γ=90.00°, V=1554.95(19) A3, T= 293(2) K, Z=2, reflections collected/unique 10203/5658 (Rint=0.0299), number of observations [>2σ(I)] 4107, parameters:382. Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre, CCDC 980203.
33 For recent reviews of multicomponent reactions, see:(a) Domling, A.; Ugi, I. Angew. Chem. Int. Ed.2000,39,3168. (b) Zhu, J. Eur. J. Org. Chem.2003,1133. (c) Orru, R. V. A.; de Greef, M. Synthesis 2003,1471. (d) Bienayme, H.; Hulme, C.; Oddon, G.; Schmitt, P. Chem. Eur. J.2000,6,3321. (e) Tietze, L. F.; Modi, A. Med. Res. Rev.2000,20,304. For recent examples of multicomponent cycloadditions, see:(f) Wender, P. A.; Croatt, M. P.; Deschamps, N. M. J. Am. Chem. Soc.2004,126,5948. (g) Ni, Y.; Montgomery, J. J. Am. Chem. Soc.2004, 43,11162. (h) Wender, P. A.; Deschamps, N. M.; Williams, T. J. Angew. Chem., Int. Ed.2004,43,3076. (i) Wender, P. A.; Deschamps, N. M.; Gamber, G. G. Angew. Chem., Int. Ed.2003,42,1853. (j) Gilbertson, S. R.; DeBoef, B. J. Am. Chem. Soc.2002,124,8784. (k) Evans, P. A.; Robinson, J. E.; Baum, E. W.; Fazal, A. N. J. Am. Chem. Soc 2002,124,8782. (1) Wender, P.A.; Gamber, G. G.; Hubbard, R. D.; Zhang, L. J. Am. Chem. Soc.2002,124,2876. (m) Neumann, H.; von Wangelin, A. J.; Gordes, D.; Spannenberg, A.; Beller, M.J. Am. Chem. Soc. 2001,123,8398. (n) Wipf, P.; Kendall, C; Stephenson, C. R. J. J. Am. Chem. Soc. 2001,123,5122.
34 (a) Ammenn, J.; Paal, M.; Ruehter, G.; Schotten, T.; Stenzel, W. PCT Int. Appl. WO 2000078724,2000. (b) Ahmed, G.; Bohnstedt, A.; Breslin, H. J.; Burke, J.; Curry, M. A.; Diebold, J. L.; Dorsey, B.; Dugan, B. J.; Feng, D.; Gingrich, D. E.; Guo, T.; Ho, K.-K.; Learn, K. S.; Lisko, J. G.; Liu, R.-Q.; Mesaros, E. F.; Milkiewicz, K.; Ott, G. R.; Parrish, J.; Theroff, J. P.; Thieu, T. V.; Tripathy, R.; Underiner, T. L.; Wagner, J. C.; Weinberg, L.; Wells, G. J.; You, M.; Zificsak, C. A. PCT Int. Appl. WO 2008051547,2008.
35 Luo, H.; Ma, S. Eur. J. Org. Chem.2013,3041.
36 Li, J.; Kong, W.; Fu, C.; Ma S., J. Org. Chem.2009,74,5104.
37 Kong, W.; Fu, C.; Ma, S. Org. Biomol. Chem.,2008,6,4587.
38 Xu,D.; Li,Z.; Ma,S.Chin.J. Chem.2004,22,310.
39 Ma,S.; Liu,J.; Li,S.; Chen,B.; Cheng,J.; Kuang,J; Liu,Y.; Wan,B.; Wang,Y.; Ye,J.; Yu,Q.; Yuan,W.; Yu,S.Adv.Synth.Catal.2011,353,1005.
40 Crystal data for compound 35a:C23H23N06S,MW=441.48,Triclinic,space group P-1,final R indices [I>2σ(I)],R1=0.0578,wR2=0.1489; R indices(all data),R1 =0.0593,wR2=0.1517; a=10.2477(5)A,b=10.6579(5)A,c=11.7877(6)A,α =97.6360(10)°,β=99.7840(10)°,γ=117.3550(10)°,γ=1093.62(9)A3,T=173(2) K,Z=2,reflections collected/unique 12886/3836(Rint=0.1482),number of observations[>2σ(I)]3635,parameters: 288.Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,CCDC 779702.
41 Xing,S.; Pan,W.; Liu,C.; Ren,J.; Wang,Z. Angew.Chem.Int. Ed.2010,49, 3215.
42 Crystal data for compound(1R,9R,10R)-39:C29H35N06S,MW=525.64, orthorhombic,space group P 21 21 21,final R indices [I>2σ(I)],R1=0.0558, wR2=0.1245; R indices(all data),R1=0.0886,wR2=0.1425; a=9.1890(8)A,b =9.7049(6)A,c=31.734(2)A,α=90°,β=90°,γ=90°,V=2830.0(4)A3,T= 293(2)K, Z=4,reflections collected/unique 14771/5160(Rint=0.0385),number of observations[>2σ(I)]3568,parameters:361.Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,CCDC 879379.
43 Crystal data for compound 40f=C68H5608,MW=1001.13,monoclinic,space group P2(1)/c,final R indices [I>26(I)],R1=0.0496,wR2=0.0934; R indices (all data),R1=0.1132,wR2=0.1131；a=10.6114(6)A,b=10.5287(6)A,c= 46.396(3)A,a=90°,β=98.255(2)°,γ=90°,V=5129.8(5)A3,T=173(2)K,Z= 4,reflections collected/unique 68695/12248(Rint=0.0818),number of observations[>2σ(I)]6982,parameters:717.Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,CCDC 779703.
44 Crystal data for compound(1R,9R,10R)-40j:C2.27H1.73Cl0.1300.27,MW=37.96, monoclinic,space group P2(1),final R indices [I>2σ(I)],R1=0.0234,wR2= 0.0632；R indices(all data),R1=0.0239,wR2=0.0637; a=8.1646(3)A,b= 5.2885(2) A, c=16.1885(6) A, α=90°, β=99.2100(10)°, γ=90°, V=689.98(4) A3, T=173(2) K, Z=15, reflections collected/unique 7972/2408 (Rint=0.0164), number of observations [>2σ(I)] 2362, parameters:189. Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre, CCDC 779701.
45 S. Ma, N. Jiao, Q. Yang, Zheng, Z.J. Org. Chem.2004,69,6463.
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32 Crystal data for compound (S,E)-31:C30H37N5O6S, MW=595.71, monoclinic, space group P 21, final R indices [I>2σ(I)], R1=0.0692, wR2=0.1882; R indices (all data), R1=0.0950, wR2=0.2221; a=9.9096(7) A, b=10.1964(7) A, c= 15.3893(12) A, a=90.00°,β=90.267(6)°,γ=90.00°, V=1554.95(19) A3, T= 293(2) K, Z=2, reflections collected/unique 10203/5658 (Rint=0.0299), number of observations [>2σ(I)] 4107, parameters:382. Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre, CCDC 980203.
33 For recent reviews of multicomponent reactions, see:(a) Domling, A.; Ugi, I. Angew. Chem. Int. Ed.2000,39,3168. (b) Zhu, J. Eur. J. Org. Chem.2003,1133. (c) Orru, R. V. A.; de Greef, M. Synthesis 2003,1471. (d) Bienayme, H.; Hulme, C.; Oddon, G.; Schmitt, P. Chem. Eur. J.2000,6,3321. (e) Tietze, L. F.; Modi, A. Med. Res. Rev.2000,20,304. For recent examples of multicomponent cycloadditions, see:(f) Wender, P. A.; Croatt, M. P.; Deschamps, N. M. J. Am. Chem. Soc.2004,126,5948. (g) Ni, Y.; Montgomery, J. J. Am. Chem. Soc.2004, 43,11162. (h) Wender, P. A.; Deschamps, N. M.; Williams, T. J. Angew. Chem., Int. Ed.2004,43,3076. (i) Wender, P. A.; Deschamps, N. M.; Gamber, G. G. Angew. Chem., Int. Ed.2003,42,1853. (j) Gilbertson, S. R.; DeBoef, B. J. Am. Chem. Soc.2002,124,8784. (k) Evans, P. A.; Robinson, J. E.; Baum, E. W.; Fazal, A. N. J. Am. Chem. Soc 2002,124,8782. (1) Wender, P.A.; Gamber, G. G.; Hubbard, R. D.; Zhang, L. J. Am. Chem. Soc.2002,124,2876. (m) Neumann, H.; von Wangelin, A. J.; Gordes, D.; Spannenberg, A.; Beller, M.J. Am. Chem. Soc. 2001,123,8398. (n) Wipf, P.; Kendall, C; Stephenson, C. R. J. J. Am. Chem. Soc. 2001,123,5122.
34 (a) Ammenn, J.; Paal, M.; Ruehter, G.; Schotten, T.; Stenzel, W. PCT Int. Appl. WO 2000078724,2000. (b) Ahmed, G.; Bohnstedt, A.; Breslin, H. J.; Burke, J.; Curry, M. A.; Diebold, J. L.; Dorsey, B.; Dugan, B. J.; Feng, D.; Gingrich, D. E.; Guo, T.; Ho, K.-K.; Learn, K. S.; Lisko, J. G.; Liu, R.-Q.; Mesaros, E. F.; Milkiewicz, K.; Ott, G. R.; Parrish, J.; Theroff, J. P.; Thieu, T. V.; Tripathy, R.; Underiner, T. L.; Wagner, J. C.; Weinberg, L.; Wells, G. J.; You, M.; Zificsak, C. A. PCT Int. Appl. WO 2008051547,2008.
35 Luo, H.; Ma, S. Eur. J. Org. Chem.2013,3041.
36 Li, J.; Kong, W.; Fu, C.; Ma S., J. Org. Chem.2009,74,5104.
37 Kong, W.; Fu, C.; Ma, S. Org. Biomol. Chem.,2008,6,4587.
38 Xu,D.; Li,Z.; Ma,S.Chin.J. Chem.2004,22,310.
39 Ma,S.; Liu,J.; Li,S.; Chen,B.; Cheng,J.; Kuang,J; Liu,Y.; Wan,B.; Wang,Y.; Ye,J.; Yu,Q.; Yuan,W.; Yu,S.Adv.Synth.Catal.2011,353,1005.
40 Crystal data for compound 35a:C23H23N06S,MW=441.48,Triclinic,space group P-1,final R indices [I>2σ(I)],R1=0.0578,wR2=0.1489; R indices(all data),R1 =0.0593,wR2=0.1517; a=10.2477(5)A,b=10.6579(5)A,c=11.7877(6)A,α =97.6360(10)°,β=99.7840(10)°,γ=117.3550(10)°,γ=1093.62(9)A3,T=173(2) K,Z=2,reflections collected/unique 12886/3836(Rint=0.1482),number of observations[>2σ(I)]3635,parameters: 288.Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,CCDC 779702.
41 Xing,S.; Pan,W.; Liu,C.; Ren,J.; Wang,Z. Angew.Chem.Int. Ed.2010,49, 3215.
42 Crystal data for compound(1R,9R,10R)-39:C29H35N06S,MW=525.64, orthorhombic,space group P 21 21 21,final R indices [I>2σ(I)],R1=0.0558, wR2=0.1245; R indices(all data),R1=0.0886,wR2=0.1425; a=9.1890(8)A,b =9.7049(6)A,c=31.734(2)A,α=90°,β=90°,γ=90°,V=2830.0(4)A3,T= 293(2)K, Z=4,reflections collected/unique 14771/5160(Rint=0.0385),number of observations[>2σ(I)]3568,parameters:361.Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,CCDC 879379.
43 Crystal data for compound 40f=C68H5608,MW=1001.13,monoclinic,space group P2(1)/c,final R indices [I>26(I)],R1=0.0496,wR2=0.0934; R indices (all data),R1=0.1132,wR2=0.1131；a=10.6114(6)A,b=10.5287(6)A,c= 46.396(3)A,a=90°,β=98.255(2)°,γ=90°,V=5129.8(5)A3,T=173(2)K,Z= 4,reflections collected/unique 68695/12248(Rint=0.0818),number of observations[>2σ(I)]6982,parameters:717.Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,CCDC 779703.
44 Crystal data for compound(1R,9R,10R)-40j:C2.27H1.73Cl0.1300.27,MW=37.96, monoclinic,space group P2(1),final R indices [I>2σ(I)],R1=0.0234,wR2= 0.0632；R indices(all data),R1=0.0239,wR2=0.0637; a=8.1646(3)A,b= 5.2885(2) A, c=16.1885(6) A, α=90°, β=99.2100(10)°, γ=90°, V=689.98(4) A3, T=173(2) K, Z=15, reflections collected/unique 7972/2408 (Rint=0.0164), number of observations [>2σ(I)] 2362, parameters:189. Supplementary crystallographic data have been deposited at the Cambridge Crystallographic Data Centre, CCDC 779701.
45 S. Ma, N. Jiao, Q. Yang, Zheng, Z.J. Org. Chem.2004,69,6463.
46 J. Kuang, S. Ma, J. Org. Chem.2009,74,1763.
47 H. Nakamura, T. Sugiishi, Y. Tanaka, Tetrahedron Lett.2008,49,7230.
48 P. Ghorai, A. Kraus, M. Keller, C. GOtte, P. Igel, E. Schneider, D. Schnell, G. Bernhardt, S. Dove, M. Zabel, S. Elz, R. Seifert, A. Buschauer,J. Med. Chem.2008, 51,7193.
49 X. Jiang, C. Fu, S. Ma, Chem. Eur. J.2008,14,9656.
50 M. Wang, C. Fu, S. Ma, Chem. Sci.,2013,4,1016.
51 Meguro, M.; Yamamoto, Y.J. Org. Chem.1999,64,694.