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1.
Nataliya V. Maksimchuk Konstantin A. Kovalenko Vladimir P. Fedin Oxana A. Kholdeeva 《Advanced Synthesis \u0026amp; Catalysis》2010,352(17):2943-2948
The mesoporous metal‐organic framework MIL‐101 is an efficient heterogeneous catalyst for the selective allylic oxidation of alkenes with tert‐butyl hydroperoxide. The selectivity towards α,β‐unsaturated ketones reaches 86–93%. The temperature of the catalyst activation strongly affects the ketone yield. MIL‐101 is stable to chromium leaching, behaves as a true heterogeneous catalyst, can be easily recovered by filtration, and can be reused several times without loss of the catalytic performance. 相似文献
2.
Xing‐Kuan Chen Chang‐Wu Zheng Sheng‐Li Zhao Zhuo Chai Ying‐Quan Yang Gang Zhao Wei‐Guo Cao 《Advanced Synthesis \u0026amp; Catalysis》2010,352(10):1648-1652
A highly enantioselective Michael addition of cyclic 1,3‐dicarbonyl compounds to β,γ‐unsaturated α‐keto esters catalyzed by amino acid‐derived thiourea‐tertiary‐amine catalysts is presented. Using 5 mol% of a novel tyrosine‐derived thiourea catalyst, a series of chiral coumarin derivatives were obtained in excellent yields (up to 99%) and with up to 96% ee under very mild conditions within a short reaction time. 相似文献
3.
Jiefeng Shen Delong Liu Qianjin An Yangang Liu Wanbin Zhang 《Advanced Synthesis \u0026amp; Catalysis》2012,354(17):3311-3325
(2S,3aR,7aS)‐Perhydroindolic acid, the key intermediate in the synthesis of trandolapril, and its trans‐isomers, were readily prepared. These proline‐like molecules are unique in that they contain a rigid bicyclic structure, with two hydrogen atoms trans to each other at the bridgehead carbon atoms. These molecules were used successfully as chiral organocatalysts in asymmetric domino Michael addition/cyclization reactions of aldehyde esters with β,γ‐unsaturated α‐keto esters. They proved to have excellent catalytic behavior, allowing for the synthesis of multi‐substituted, enantiomerically enriched hemiacetal esters. Under optimal conditions (using 10 mol% catalyst loading), a series of β,γ‐unsaturated α‐keto esters was examined with up to 99% de, ee and yield, respectively. Additionally, the enantiomerically enriched hemiacetal esters could be readily transformed into their corresponding bioactive pyrano[2,3‐b]pyrans (possessing a multi‐substituted bicyclic backbone). 相似文献
4.
Jie Li Wei Pan Zheng Wang Xumu Zhang Kuiling Ding 《Advanced Synthesis \u0026amp; Catalysis》2012,354(10):1980-1986
The spiro‐2,2′‐bichroman‐based chiral bisoxazoline ligands (SPANbox) were found to be highly efficient in copper(II)‐ and zinc(II)‐catalyzed asymmetric chlorinations of cyclic β‐keto esters with N‐chlorosuccinimide (NCS) as the chlorination reagent, to give the corresponding α‐chloro‐β‐keto esters in excellent yields in 5–30 min with ee values up to 97%. The copper(II) triflate and zinc(II) triflate complexes of a single SPANbox ligand demonstrated complementary results to each other with respect to the enantioselection, affording both antipodes of the chlorinated product enantiomers with good to excellent optical purities. 相似文献
5.
Luca Deiana Gui‐Ling Zhao Shuangzheng Lin Pawel Dziedzic Qiong Zhang Hans Leijonmarck Armando Crdova 《Advanced Synthesis \u0026amp; Catalysis》2010,352(18):3201-3207
The first example of a highly enantioselective organocatalytic aziridination of α‐substituted α,β‐unsaturated aldehydes is presented. The reaction is catalyzed by simple chiral amines and gives access to highly functional terminal azirdines containing an α‐tertiary amine stereocenter in high yields and enantiomeric ratios (95.5:4.5–98:2). 相似文献
6.
Chengkai Yin Weidi Cao Lili Lin Xiaohua Liu Xiaoming Feng 《Advanced Synthesis \u0026amp; Catalysis》2013,355(10):1924-1930
The highly catalytic asymmetric α‐hydroxylation of 1‐tetralone‐derived β‐keto esters and β‐keto amides using tert‐butyl hydroperoxide (TBHP) as the oxidant was realized by a chiral N,N′‐dioxide‐magnesium ditriflate [Mg(OTf)2] complex. A series of corresponding chiral α‐hydroxy dicarbonyl compounds was obtained in excellent yields (up to 99%) with excellent enantioselectivities (up to 98% ee). The products were easily transformed into useful building blocks and the precursor of daunomycin was achieved in an asymmetric catalytic way for the first time. 相似文献
7.
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
8.
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
9.
Dianjun Li Tonghao Yang Hailin Su Wei Yu 《Advanced Synthesis \u0026amp; Catalysis》2015,357(11):2529-2539
The oxidizing system of tert‐butyl hydroperoxide (TBHP) and tetrabutylammonium iodide (TBAI) is capable of generating α‐(arylaminocarbonyl)iminyl radicals from ethyl 2‐(N‐arylcarbamoyl)‐2‐iminoacetates. These iminyl radicals preferably undergo intramolecular ipso attack on the benzene ring to give azaspirocyclohexadienyl radicals, which are readily captured by molecular oxygen under an oxygen atmosphere to yield azaspirocyclohexadienones. In the absence of oxygen, the reaction affords quinoxalin‐2‐one products. This oxidizing system is also effective to convert α‐aryl‐α‐azido‐N‐arylamides to the corresponding iminyl radicals under basic conditions (sodium tert‐butoxide, t‐BuONa), and the subsequent cyclization of these iminyl radicals results in the formation of azaspirocyclohexadienone products in high yields under an oxygen atmosphere. Plausible mechanisms are proposed to rationalize the experimental results, and factors influencing the reactions are discussed.
10.
Dennis U. Nielsen Signe Korsager Anders T. Lindhardt Troels Skrydstrup 《Advanced Synthesis \u0026amp; Catalysis》2014,356(17):3519-3524
An efficient three‐component reaction involving carbon monoxide with a range of aryl bromides and N‐substituted acetoacetamides is reported for the synthesis of β‐keto amides. This transformation is promoted by Pd‐catalysis followed by an acid‐mediated deacetylation upon work‐up, enabling a large number of β‐keto amides to be isolated. Finally, d2‐13C‐dyclonine could be synthesized in three steps utilizing the developed catalytic system as the key step.
11.
Zugui Shi Peiyuan Yu Pei Juan Chua Guofu Zhong 《Advanced Synthesis \u0026amp; Catalysis》2009,351(17):2797-2800
In the presence of the readily available quinine‐derived catalyst 4d , highly diastereo‐ and enantioselective Mannich reactions of tosyl‐protected imines and α‐isothiocyanato imides proceeded to afford the protected α,β‐diamino acids, useful building blocks for natural products and biologically active compounds, in good to excellent yields. 相似文献
12.
Gaetano Giammona Gennara Cavallaro Giovanna Pitarresi Elisa Pedone 《Polymer International》2000,49(1):93-98
In the present study the derivatization of two water‐soluble synthetic polymers, α,β‐poly(N‐2‐hydroxyethyl)‐DL ‐aspartamide (PHEA) and α,β‐polyasparthylhydrazide (PAHy), with glycidyltrimethylammonium chloride (GTA) is described. This reaction permits the introduction of positive charges in the macromolecular chains of PHEA and PAHy in order to make easier the electrostatic interaction with DNA. Different parameters affect the reaction of derivatization, such as GTA concentration and reaction time. PHEA reacts partially and slowly with GTA; on the contrary the reaction of PAHy with GTA is more rapid and extensive. The derivatization of PHEA and PAHy with GTA is a convenient method to introduce positive groups in their chains and it permits the preparation of interpolyelectrolyte complexes with DNA. © 2000 Society of Chemical Industry 相似文献
13.
Jian Li Yin‐Long Li Nan Jin Ai‐Lun Ma Ya‐Nan Huang Jun Deng 《Advanced Synthesis \u0026amp; Catalysis》2015,357(11):2474-2478
A practical and novel process for the decarboxylative fluorination of β‐ketoacids in water in the presence of phase transfer catalyst has been developed, affording a series of α‐fluoroketones in good to excellent yields. Furthermore, a preliminary investigation for the catalytic asymmetric transformation was performed and a proposed mechanistic pathway for this catalytic process was proposed.
14.
Bernhard Hagemann Kathrin Junge Stephan Enthaler Manfred Michalik Thomas Riermeier Axel Monsees Matthias Beller 《Advanced Synthesis \u0026amp; Catalysis》2005,347(15):1978-1986
17 monodentate phosphepine ligands with a 4,5‐dihydro‐3H‐dinaphtho[2,1‐c;1′,2′‐e]phosphepine structural motif have been synthesized and tested in the asymmetric hydrogenation of various β‐keto esters. By variation of the substituents of the aryl group on the phosphorus atom a fine tuning of the selectivity of the catalytic system is possible. Quantitative yield and enantioselectivities up to 95% ee have been achieved for the hydrogenation of methyl acetoacetate ( 7a ), methyl 3‐oxovalerate ( 7b ) and ethyl 4‐phenyl‐3‐oxo‐propionate ( 7d ) using 4‐(4‐methoxyphenyl)‐4,5‐dihydro‐3H‐dinaphtho‐[2,1‐c;1′,2′‐e]phosphepine ( 4g ) as ligand. Best enantioselectivities were obtained at comparably high temperatures (100–120 °C), which had the advantage of increased reaction rates. 相似文献
15.
Ji Yang Yan‐Yun Liu Ren‐Jie Song Zhi‐Hong Peng Jin‐Heng Li 《Advanced Synthesis \u0026amp; Catalysis》2016,358(14):2286-2292
A new copper‐mediated synthesis of α‐sulfonylethanone oximes from styrenes, sodium arylsulfinates and tert‐butyl nitrite (t‐BuONO; TBN) is presented. This intermolecular three‐component method enables the one‐step formation of C N and C S bonds under mild conditions, and represents a new, straightforward approach to α‐sulfonylethanone oximes.
16.
Krishna Bahadur SomaiMagar Yong Rok Lee 《Advanced Synthesis \u0026amp; Catalysis》2014,356(16):3422-3432
Efficient one‐step syntheses of α,β‐ and β,β‐dihaloenones were achieved by ruthenium(II)‐catalyzed reactions between cyclic or acyclic diazodicarbonyl compounds and oxalyl chloride or oxalyl bromide in moderate to good yields. This methodology offers several significant advantages, which include ease of handling, mild reaction conditions, one‐step reaction, and the use of an effective and non‐toxic catalyst. The synthesized compounds were further transformed into highly functionalized novel molecules bearing aromatic rings on the enone moiety using the Suzuki reaction.
17.
NataliyaS. Goulioukina GrigoriiN. Bondarenko SergeyE. Lyubimov VadimA. Davankov KonstantinN. Gavrilov IrinaP. Beletskaya 《Advanced Synthesis \u0026amp; Catalysis》2008,350(3):482-492
It was shown that the catalytic hydrogenation of α‐iminophosphonates by molecular hydrogen can serve as a convenient method for the synthesis of racemic and optically active α‐aminophosphonates. Up to 94% ee was achieved in the rhodium‐catalyzed enantioselective hydrogenation using chiral ligand (R)‐BINAP. 相似文献
18.
Koji Yonehara Yasuyuki Miyoshi Aki Tsukajima Takeo Akatsuka Makoto Saito 《Advanced Synthesis \u0026amp; Catalysis》2011,353(7):1071-1075
The methodology in this article is a palladium(II)/copper(II)‐ or palladium(II)‐catalyzed intermolecular cyclization of acrylic acid with alkenes to produce α‐methylene‐γ‐butyrolactone derivatives using molecular oxygen as an environmentally benign oxidant. In this system, the carboxylato, especially trifluoroacetato, or trimethylacetato ligand, plays a quite important role to afford a high catalytic activity by suppressing the deposition of palladium(0) black. 相似文献
19.
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
20.
Makoto Hibi Takuya Kasahara Takashi Kawashima Hiroko Yajima Shoko Kozono Sergey V. Smirnov Tomohiro Kodera Masakazu Sugiyama Sakayu Shimizu Kenzo Yokozeki Jun Ogawa 《Advanced Synthesis \u0026amp; Catalysis》2015,357(4):767-774
A novel enzymatic production system of optically pure β‐hydroxy α‐amino acids was developed. Two enzymes were used for the system: an N‐succinyl L ‐amino acid β‐hydroxylase (SadA) belonging to the iron(II)/α‐ketoglutarate‐dependent dioxygenase superfamily and an N‐succinyl L ‐amino acid desuccinylase (LasA). The genes encoding the two enzymes are part of a gene set responsible for the biosynthesis of peptidyl compounds found in the Burkholderia ambifaria AMMD genome. SadA stereoselectively hydroxylated several N‐succinyl aliphatic L ‐amino acids and produced N‐succinyl β‐hydroxy L ‐amino acids, such as N‐succinyl‐L ‐β‐hydroxyvaline, N‐succinyl‐L ‐threonine, (2S,3R)‐N‐succinyl‐L ‐β‐hydroxyisoleucine, and N‐succinyl‐L ‐threo‐β‐hydroxyleucine. LasA catalyzed the desuccinylation of various N‐succinyl‐L ‐amino acids. Surprisingly, LasA is the first amide bond‐forming enzyme belonging to the amidohydrolase superfamily, and has succinylation activity towards the amino group of L ‐leucine. By combining SadA and LasA in a preparative scale production using N‐succinyl‐L ‐leucine as substrate, 2.3 mmol of L ‐threo‐β‐hydroxyleucine were successfully produced with 93% conversion and over 99% of diastereomeric excess. Consequently, the new production system described in this study has advantages in optical purity and reaction efficiency for application in the mass production of several β‐hydroxy α‐amino acids.