共查询到20条相似文献,搜索用时 15 毫秒
1.
Huiling Geng Xiaowei Zhang Mingxin Chang Le Zhou Wenjun Wu Xumu Zhang 《Advanced Synthesis \u0026amp; Catalysis》2011,353(16):3039-3043
A highly efficient and enantioselective hydrogenation of unprotected β‐ketoenamines catalyzed with ruthenium(II) dichloro{(S)‐(−)‐2,2′‐bis[di(3,5‐xylyl)phosphino]‐1,1′‐binaphthyl}[(2S)‐(+)‐1,1‐bis(4‐methoxyphenyl)‐3‐methyl‐1,2‐butanediamine] {Ru[(S)‐xylbinap][(S)‐daipen]Cl2} has been successfully developed. This methodology provides a straightforward access to free γ‐secondary amino alcohols, which are key building blocks for a variety of pharmaceuticals and natural products, with high yields (>99%) and excellent enantioselectivities (up to 99% ee) in all cases. 相似文献
2.
Xianfeng Sun Wei Li Guohua Hou Le Zhou Xumu Zhang 《Advanced Synthesis \u0026amp; Catalysis》2009,351(16):2553-2557
A highly efficient strategy for the synthesis of a series of C3*‐TunePhos chiral diphosphine ligands was well established with several remarkable features. The synthetic utility of these ligands was explored for the ruthenium‐catalyzed asymmetric hydrogenation of β‐keto esters. Up to 99% ee values were achieved for the enantioselective synthesis of β‐hydroxy acid derivatives, which are very important chiral building blocks for the synthesis of a variety of natural products and biologically active molecules. 相似文献
3.
Man Liu Duanyang Kong Meina Li Guofu Zi Guohua Hou 《Advanced Synthesis \u0026amp; Catalysis》2015,357(18):3875-3879
A highly efficient, iridium‐catalyzed, enantioselective hydrogenation of β,β‐disubstituted nitroalkenes has been developed. Using a complex consisting of iridium and (S,S)‐f‐spiroPhos as the catalyst, a variety of β,β‐disubstituted nitroalkenes were successfully hydrogenated to the corresponding chiral nitroalkanes with excellent enantioselectivities (up to 98% ee) and high turnover numbers (TON=1000).
4.
Jian‐Zhou Huang Xiang Wu Liu‐Zhu Gong 《Advanced Synthesis \u0026amp; Catalysis》2013,355(13):2531-2537
An enantioselective organocatalytic addition of nitroalkanes to oxindolylideneindolenines in the presence of bifunctional organocatalysts has been established to provide an efficient entry to 3,3‐disubstituted oxindole derivatives in high yields and with excellent enantioselectivities. The transformation has been applied to the preparation of the key intermediate for a formal total synthesis of (+)‐gliocladin C.
5.
6.
Palle Breistein Jonas Johansson Ismail Ibrahem Shuangzheng Lin Luca Deiana Junliang Sun Armando Cordova 《Advanced Synthesis \u0026amp; Catalysis》2012,354(6):1156-1162
The highly enantioselective cascade reaction between N‐protected α‐cyanoglycine esters and α,β‐unsaturated aldehydes is disclosed. The reaction represents a one‐step entry to polysubstituted 5‐hydroxyproline derivatives having a quaternary α‐stereocenter generally in high yields with up to >95:5 dr and 99:1 er. It is also a direct catalytic two‐step entry to functionalized α‐quaternary proline derivatives. 相似文献
7.
Li‐Jie Cheng Jian‐Hua Xie Li‐Xin Wang Qi‐Lin Zhou 《Advanced Synthesis \u0026amp; Catalysis》2012,354(6):1105-1113
A new and efficient catalytic asymmetric synthesis of the potent cannabinoid receptor agonist (−)‐CP‐55940 has been developed by using ruthenium‐catalyzed asymmetric hydrogenation of racemic α‐aryl ketones via dynamic kinetic resolution (DKR) as a key step. With RuCl2‐SDPs/diamine [SDPs=7,7′‐bis(diarylphophino)‐1,1′‐spirobiindane] catalysts the asymmetric hydrogenation of racemic α‐arylcyclohexanones via DKR provided the corresponding cis‐β‐arylcyclohexanols in high yields with up to 99.3% ee and >99:1 cis‐selectivities. Both ethylene ketal group at the cyclohexane ring and ortho‐methoxy group at the phenyl ring of the substrates 6 have little effect on the selectivity and reactivity of the hydrogenations. Based on this highly efficient asymmetric ketone hydrogenation, (−)‐CP‐55940 was synthesized in 13 steps (the longest linear steps) in 14.6% overall yield starting from commercially available 3‐methoxybenzaldehyde and 1,4‐cyclohexenedione monoethylene acetal. 相似文献
8.
Lu‐Jia Zhou Yu‐Chen Zhang Fei Jiang Guofeng He Jingjing Yan Han Lu Shu Zhang Feng Shi 《Advanced Synthesis \u0026amp; Catalysis》2016,358(19):3069-3083
The first catalytic asymmetric construction of the cyclic enaminone‐based 3‐substituted 3‐amino‐2‐oxindole scaffold with potential bioactivity has been developed via chiral phosphoric acid‐catalyzed enantioselective addition reactions of cyclic enaminones to isatin‐derived imines, which afforded a series of cyclic enaminone‐based 3‐substituted 3‐amino‐2‐oxindoles in high yields and excellent enantioselectivities (up to 99% yield, 97% ee). The investigation of the reaction mechanism suggested that it was facilitated by a dual hydrogen‐bonding activation mode between the two substrates and the chiral phosphoric acid. Besides, this method could be utilized for a large‐scale synthesis with maintained enantioselectivity. This approach will not only offer a useful method for enantioselective construction of the cyclic enaminone‐based 3‐substituted 3‐amino‐2‐oxindole scaffold, but also enrich the research on catalytic asymmetric addition reactions of isatin‐derived imines by using electron‐rich olefins as nucleophiles. More importantly, a preliminary evaluation on the cytotoxicity of some selected products revealed that two of the enantio‐pure compounds exhibited moderate to strong cytotoxicity to A549, 786‐0, ECA109 and BT474 cancer cell lines.
9.
Xianfeng Sun Wei Li Le Zhou Xumu Zhang 《Advanced Synthesis \u0026amp; Catalysis》2010,352(7):1150-1154
A highly efficient strategy for the synthesis of a series of chiral bisaminophosphine ligands was well established with several remarkable features. The synthetic utility of these ligands was explored for rhodium‐catalyzed asymmetric hydrogenations of α‐dehydroamino acid esters. Up to 98% ee values were achieved for the enantioselective synthesis of aminocarboxylic acids and their derivatives, which are very important chiral building blocks for the synthesis of a variety of natural products and biologically active molecules. 相似文献
10.
Jun Wang Zhihui Shao Kai Ding Wing Yiu Yu Albert S.C. Chan 《Advanced Synthesis \u0026amp; Catalysis》2009,351(9):1250-1254
11.
Min Qiu Xiang‐Ping Hu Dao‐Yong Wang Jun Deng Jia‐Di Huang Sai‐Bo Yu Zheng‐Chao Duan Zhuo Zheng 《Advanced Synthesis \u0026amp; Catalysis》2008,350(9):1413-1418
We have recently reported a new chiral 1,2,3,4‐tetrahydro‐1‐naphthylamine‐derived phosphine‐phosphoramidite ligand, (Rc,Ra)‐THNAPhos, that is highly efficient in the rhodium‐catalyzed asymmetric hydrogenation of a broad range of α‐enol ester phosphonates. To further demonstrate the utility of THNAPhos in asymmetric hydrogenation, in this paper, we describe its new application in the asymmetric hydrogenation of α‐dehydroamino acid esters, enamides, dimethyl itaconate and α‐enamido phosphonates. The results disclosed that the Rh/(Rc,Ra)‐THNAPhos complex is highly effective for the enantioselective hydrogenation of these kinds of functionalized CC olefins, affording the corresponding hydrogenation product in excellent enantioselectivities (normally over 99% ee). 相似文献
12.
Pablo Etayo Ramn Badorrey María D. Díaz‐de‐Villegas Jos A. Glvez 《Advanced Synthesis \u0026amp; Catalysis》2010,352(18):3329-3338
Highly modular chiral amino diol derivatives have been used as organocatalysts in the enantioselective α‐chlorination of cyclic β‐keto esters. Optimization of the catalyst structure and the reaction conditions has allowed the synthesis of optically active α‐chlorinated products with high enantioselectivities (up to 96% ee) using inexpensive commercially available N‐chlorosuccinimide (NCS) as the chlorine source under mild conditions. 相似文献
13.
Aijun Lin Ling Fang Xi Zhu Chengjian Zhu Yixiang Cheng 《Advanced Synthesis \u0026amp; Catalysis》2011,353(4):545-549
The highly effective and enantioselective sulfenylation of β‐keto phosphonates catalyzed by α,α‐diaryl‐L ‐prolinols has been developed. The optically active α‐sulfenylated β‐keto phosphonates could be obtained under mild reaction conditions in good yields (up to 92%) and with excellent enantioselectivities (up to 92% ee). 相似文献
14.
Yohan Park Young Ju Lee Suckchang Hong Mi‐hyun Kim Myungmo Lee Taek‐Soo Kim Jae Kyun Lee Sang‐sup Jew Hyeung‐geun Park 《Advanced Synthesis \u0026amp; Catalysis》2011,353(18):3313-3318
A new enantioselective α‐alkylation of α‐tert‐butoxycarbonyllactams for the construction of β‐quaternary chiral pyrrolidine and piperidine core systems is reported. α‐Alkylations of N‐methyl‐α‐tert‐butoxycarbonylbutyrolactam and N‐diphenylmethyl‐α‐tert‐butoxycarbonylvalerolactam under phase‐transfer catalytic conditions (solid potassium hydroxide, toluene, −40 °C) in the presence of (S,S)‐3,4,5‐trifluorophenyl‐3,3′,5,5′‐tetrahydro‐2,6‐bis(3,4,5‐trifluorophenyl)‐4,4′‐spirobi[4H‐dinaphth[2,1‐c:1′,2′‐e]azepinium] bromide [(S,S)‐NAS Br] (5 mol%) afforded the corresponding α‐alkyl‐α‐tert‐butoxycarbonyllactams in very high chemical (up to 99%) and optical yields (up to 98% ee). Our new catalytic systems provide attractive synthetic methods for pyrrolidine‐ and piperidine‐based alkaloids and chiral intermediates with β‐quaternary carbon centers. 相似文献
15.
Wing‐Sze Lam StantonH.L. Kok TerryT.‐L. Au‐Yeung Jing Wu Hong‐Yee Cheung Fuk‐Loi Lam Chi‐Hung Yeung AlbertS.C. Chan 《Advanced Synthesis \u0026amp; Catalysis》2006,348(3):370-374
P‐Phos‐ruthenium‐DPEN precatalysts have been found to be efficient for the asymmetric hydrogenation of various ferrocenyl ketones. The use of (R)‐xylyl‐P‐PhosRuCl2(R,R)‐DPEN generated chiral ferrocenylethanol in 99.3% e.e. with >99% conversion in a 150‐g scale. 相似文献
16.
Magnus Rueping Sadiya Raja Alberto Núez 《Advanced Synthesis \u0026amp; Catalysis》2011,353(4):563-568
A new enantioselective Brønsted acid‐catalyzed Friedel–Crafts reaction of indole with cyclic imines has been develeoped. This organocatalytic reaction provides for the first time optically active indolindolinone derivatives in high yields and with excellent enantioselectivities (up to 91% ee) under mild reaction conditions. 相似文献
17.
Fares Ibrahim Amr Carlos Vila Gonzalo Blay M. Carmen Muoz Jos R. Pedro 《Advanced Synthesis \u0026amp; Catalysis》2016,358(10):1583-1588
A quinine‐derived thiourea catalysed the enantioselective addition of 4‐substituted pyrazolones to isatin‐derived ketimines, providing a variety of aminooxindole‐pyrazolone adducts containing congested vicinal tetrasubstituted stereocentres with excellent outcomes (up to 98% yield, >20:1 dr and 98% ee).
18.
Yujuan Guo Guang Shao Lanning Li Wenhao Wu Ruihong Li Jingjing Li Jian Song Liqin Qiu Mahavir Prashad Fuk Yee Kwong 《Advanced Synthesis \u0026amp; Catalysis》2010,352(9):1539-1553
A new strategy was developed for the synthesis of a valuable class of α‐aminomethylacrylates via the Baylis–Hillman reaction of different aldehydes with methyl acrylate followed by acetylation of the resulting allylic alcohols and SN2′‐type amination of the allylic acetates. Asymmetric hydrogenation of these diverse olefinic precursors using rhodium(Et‐Duphos) catalysts provided the corresponding β2‐amino acid derivatives with excellent enantioselectivities and exceedingly high reactivities (up to >99.5% ee and S/C=10,000). The first hydrogenation of (Z)‐configurated substrates was studied for the synthesis of β2‐amino acid derivatives. The high influence of the substrate geometry and steric hindrance on the reactivity and enantioselectivity was also disclosed for this reaction. This protocol provides a highly practical, facile and scalable method for the preparation of optically pure β2‐amino acids and their derivatives under mild reaction conditions. 相似文献
19.
Chihliang Chang Ssu‐Hsien Li Raju Jannapu Reddy Kwunmin Chen 《Advanced Synthesis \u0026amp; Catalysis》2009,351(9):1273-1278
20.
Wen‐Ju Bai Jian‐Hua Xie Ya‐Li Li Sheng Liu Qi‐Lin Zhou 《Advanced Synthesis \u0026amp; Catalysis》2010,352(1):81-84
A highly efficient enantioselective synthesis of chiral β‐aryloxy alcohols by the {RuCl2[(S)‐SDP][(R,R)‐DPEN]} [(Sa,R,R)‐ 1a ; SDP=7,7′‐bis(diarylphosphino)‐1,1′‐spirobiindane; DPEN=trans‐1,2‐diphenylethylenediamine] complex‐catalyzed asymmetric hydrogenation of racemic α‐aryloxydialkyl ketones via dynamic kinetic resolution (DKR) has been developed. Enantioselectivities of up to 99% ee with good to high cis/anti‐selectivities (up to>99:1) were achieved. 相似文献