Thematische Bibliographien / Bifunctional chiral catalysts

Inhaltsverzeichnis

Zeitschriftenartikel
Dissertationen
Buchteile

Auswahl der wissenschaftlichen Literatur zum Thema „Bifunctional chiral catalysts“

Autor: Grafiati

Veröffentlicht am 18. Mai 2024

Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an

Wählen Sie eine Art der Quelle aus:

Machen Sie sich mit den Listen der aktuellen Artikel, Bücher, Dissertationen, Berichten und anderer wissenschaftlichen Quellen zum Thema "Bifunctional chiral catalysts" bekannt.

Neben jedem Werk im Literaturverzeichnis ist die Option "Zur Bibliographie hinzufügen" verfügbar. Nutzen Sie sie, wird Ihre bibliographische Angabe des gewählten Werkes nach der nötigen Zitierweise (APA, MLA, Harvard, Chicago, Vancouver usw.) automatisch gestaltet.

Sie können auch den vollen Text der wissenschaftlichen Publikation im PDF-Format herunterladen und eine Online-Annotation der Arbeit lesen, wenn die relevanten Parameter in den Metadaten verfügbar sind.

Zeitschriftenartikel zum Thema "Bifunctional chiral catalysts"

Vazquez-Chavez, Josué, Socorro Luna-Morales, Diego A. Cruz-Aguilar, Howard Díaz-Salazar, Wilmer E. Vallejo Narváez, Rodrigo S. Silva-Gutiérrez, Simón Hernández-Ortega, Tomás Rocha-Rinza und Marcos Hernández-Rodríguez. „The effect of chiral N-substituents with methyl or trifluoromethyl groups on the catalytic performance of mono- and bifunctional thioureas“. Organic & Biomolecular Chemistry 17, Nr. 47 (2019): 10045–51. http://dx.doi.org/10.1039/c9ob01893j.

Der volle Inhalt der Quelle

Annotation:

Thiourea organocatalysts with a chiral group containing a trifluoromethyl moiety have better hydrogen bonding properties. However, not all reactions catalysed by bifunctional catalysts are enhanced by stronger NH acidity.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Chen, Jianfeng, Xing Gong, Jianyu Li, Yingkun Li, Jiguo Ma, Chengkang Hou, Guoqing Zhao, Weicheng Yuan und Baoguo Zhao. „Carbonyl catalysis enables a biomimetic asymmetric Mannich reaction“. Science 360, Nr. 6396 (28.06.2018): 1438–42. http://dx.doi.org/10.1126/science.aat4210.

Der volle Inhalt der Quelle

Annotation:

Chiral amines are widely used as catalysts in asymmetric synthesis to activate carbonyl groups for α-functionalization. Carbonyl catalysis reverses that strategy by using a carbonyl group to activate a primary amine. Inspired by biological carbonyl catalysis, which is exemplified by reactions of pyridoxal-dependent enzymes, we developed an N-quaternized pyridoxal catalyst for the asymmetric Mannich reaction of glycinate with aryl N-diphenylphosphinyl imines. The catalyst exhibits high activity and stereoselectivity, likely enabled by enzyme-like cooperative bifunctional activation of the substrates. Our work demonstrates the catalytic utility of the pyridoxal moiety in asymmetric catalysis.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Wu, Jia-Hong, Jianke Pan und Tianli Wang. „Dipeptide-Based Phosphonium Salt Catalysis: Application to Enantioselective Synthesis of Fused Tri- and Tetrasubstituted Aziridines“. Synlett 30, Nr. 19 (27.08.2019): 2101–6. http://dx.doi.org/10.1055/s-0039-1690192.

Der volle Inhalt der Quelle

Annotation:

Over the past decades, phase-transfer catalysis (PTC), generally based on numerous chiral quaternary ammonium salts, has been recognized as a powerful and versatile tool for organic synthesis in both industry and academia. In sharp contrast, PTC involving chiral phosphonium salts as the catalysts is insufficiently developed. Recently, our group realized the first enantioselective aza-Darzens reaction for preparing tri- and tetrasubstituted aziridine derivatives under bifunctional phosphonium salt catalysis. This article briefly discusses the recent development in asymmetric reactions (mainly including nucleophilic additions and cyclizations) promoted by chiral quaternary phosphonium salt catalysts. We expect that more catalytic asymmetric reactions will be developed on the basis of such new phase-transfer catalytic systems in the near future.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Hu, Xiao-Mu, Rui Zhang, Hai Dong, Yan-Yan Jia, Guo-Qiang Bao und Ping-An Wang. „Chiral bifunctional organocatalysts for enantioselective synthesis of 3-substituted isoindolinones“. RSC Advances 13, Nr. 35 (2023): 24460–65. http://dx.doi.org/10.1039/d3ra04350a.

Der volle Inhalt der Quelle

Annotation:

Chiral tertiary-amine catalysts with a urea group can afford 3-substituted isoindolinones both in higher yields (87% vs. 77%) and enantioselectivities (95% ee vs. 46% ee) than chiral bifunctional phase-transfer catalysts under mild conditions.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Yoshida, Yasushi, Tatsuya Ao, Takashi Mino und Masami Sakamoto. „Chiral Bromonium Salt (Hypervalent Bromine(III)) with N-Nitrosamine as a Halogen-Bonding Bifunctional Catalyst“. Molecules 28, Nr. 1 (02.01.2023): 384. http://dx.doi.org/10.3390/molecules28010384.

Der volle Inhalt der Quelle

Annotation:

There has been a great focus on halogen-bonding as a unique interaction between electron-deficient halogen atoms with Lewis basic moieties. Although the application of halogen-bonded atoms in organic chemistry has been eagerly researched in these decades, the development of chiral molecules with halogen-bonding functionalities and their utilization in asymmetric catalysis are still in the\ir infancy. We have previously developed chiral halonium salts with amide functionalities, which behaved as excellent catalysts albeit in only two reactions due to the lack of substrate activation abilities. In this manuscript, we have developed chiral halonium salts with an N-nitrosamine moiety and applied them to the Mannich reaction of isatin-derived ketimines with malonic esters. The study focused on our novel bromonium salt catalyst which provided the corresponding products in high yields with up to 80% ee. DFT calculations of the chiral catalyst structure suggested that the high asymmetric induction abilities of this catalyst are due to the Lewis basic role of the N-nitrosamine part. To the best of our knowledge, this is the first catalytic application of N-nitrosamines.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Kamal, Shagufta, Ameer Fawad Zahoor, Sajjad Ahmad, Rabia Akhtar, Iqra Khaliq, Wajiha Qurban und Attia Mehreen. „Recent Trends in the Development of Novel Catalysts for Asymmetric Michael Reaction“. Current Organic Chemistry 24, Nr. 13 (01.10.2020): 1397–458. http://dx.doi.org/10.2174/1385272824999200616123744.

Der volle Inhalt der Quelle

Annotation:

: Michael reaction is the nucleophilic addition of active methylene compounds to conjugated olefins, resultantly affording a variety of biologically active scaffolds with high enantiopurity. To improve the reaction yield, as well as enantioselectivity of the product, a variety of catalysts (amine-based catalysts, bifunctional L-proline amides, bifunctional squaramides, chiral ionic liquids, cinchona alkaloids, enzymes, indolinols, metal catalysts, peptide derived catalytic system, phase transfer catalysts, pyrrolidine based organocatalysts) have been investigated by a different era of chemists. Besides this, different methodologies have been developed to improve reaction yield and enantioselectivity of the targeted products with low catalyst loading. : This review article provides a concise overview of the catalysts applied recently by different scientists in the Michael addition reaction. Moreover, current strategies and potential applications of this reaction have also been illustrated in this review.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Kitamura, Masato, Kengo Miyata, Tomoaki Seki, Namdev Vatmurge und Shinji Tanaka. „CpRu-catalyzed asymmetric dehydrative allylation“. Pure and Applied Chemistry 85, Nr. 6 (15.04.2013): 1121–32. http://dx.doi.org/10.1351/pac-con-12-10-02.

Der volle Inhalt der Quelle

Annotation:

Asymmetric Tsuji–Trost allylation is one of the key chiral technologies for construction of pharmaceutically important compounds because of the high utility of alkenyl-substituted products. Particularly, the dehydrative system using allylic alcohols and protic nucleophiles has started to attract the attention of organic synthetic chemists from the viewpoints of atom and step economy, environmental benignity, and operational simplicity. In this paper, two types of new chiral CpRu catalysts, which have been developed on the basis of redox-mediated donor–acceptor bifunctional catalyst (RDACat) concept, are presented. Complementary use of the chiral catalysts has realized the syntheses of a wide rage of carbocyclic compounds, saturated N- or O-heterocyclic compounds with high reactivity, regioselectivity, enantioselectivity, productivity, and generality.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Ikariya, Takao, Shigeki Kuwata und Yoshihito Kayaki. „Aerobic oxidation with bifunctional molecular catalysts“. Pure and Applied Chemistry 82, Nr. 7 (04.05.2010): 1471–83. http://dx.doi.org/10.1351/pac-con-09-09-11.

Der volle Inhalt der Quelle

Annotation:

A new series of half-sandwich group 8 and 9 metal complexes bearing a metal/NH bifunctional moiety were synthesized from benzylic amines. The isolable Ir amide complexes serve as effective catalysts for aerobic oxidative transformation of secondary and primary alcohols into the corresponding ketones and esters under mild conditions. The aerobic oxidative kinetic resolution of racemic secondary alcohols with chiral bifunctional Ir catalysts was found to proceed smoothly under mild conditions with high selectivity. A novel imido-bridged dirhodium complex, which may be regarded as a dinuclear variant of the bifunctional mononuclear amide complexes, also proved to promote aerobic oxidation of a secondary alcohol and H2.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Ruan, Sai, Xiaobin Lin, Lihua Xie, Lili Lin, Xiaoming Feng und Xiaohua Liu. „Asymmetric synthesis of 3-aminodihydrocoumarins via the chiral guanidine catalyzed cascade reaction of azlactones“. Organic Chemistry Frontiers 5, Nr. 1 (2018): 32–35. http://dx.doi.org/10.1039/c7qo00768j.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Nishiyori, Ryuichi, Ken Okuno, Bun Chan und Seiji Shirakawa. „Chiral Bifunctional Selenide Catalysts for Asymmetric Iodolactonizations“. Chemical and Pharmaceutical Bulletin 70, Nr. 9 (01.09.2022): 599–604. http://dx.doi.org/10.1248/cpb.c22-00049.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Mehr Quellen

Dissertationen zum Thema "Bifunctional chiral catalysts"

Kong, Julie. „Design, synthesis and applications of new chiral bifunctional iminophosphorane - thiourea organocatalysts. Organophotocatalytic addition of unactivated alkenes with silicon enolate“. Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASF018.

Der volle Inhalt der Quelle

Annotation:

Ce travail de thèse porte sur le développement de nouveaux organocatalyseurs chiraux bifonctionnels et leurs applications en organocatalyse asymétrique. Pour ce faire, nous avons d'abord étudié la conception et la synthèse de nouveaux organocatalyseurs chiraux possédant une fonction iminophosphorane, d'une part et une fonction donneuse de liaison hydrogène, d'autre part. Ainsi, plusieurs familles d'organocatalyseurs chiraux bifonctionnels à base de L-proline et d'acide (S)-pyroglutamique ont été synthétisées en quelques étapes avec des rendements globaux modérés à bons. Ces nouveaux catalyseurs ont été évalués par la suite dans diverses réactions asymétriques. Le grand potentiel de ces catalyseurs a été démontré dans la synthèse d'α-acyloxythioester par transfert d'acyle suivi d'une protonation énantiosélective via l'intermédiaire énolate d'α-acyloxy-β-cétosulfure. De très bons rendements (jusqu'à 94 %) et énantiosélectivités (jusqu'à 98 %) ont été obtenus. Le catalyseur le plus performant a été ensuite immobilisé sur support résine et évalué dans la même réaction. D'une manière générale, les réactions se sont bien déroulées conduisant à la formation des produits attendus avec de bons rendements et énantiosélectivités. Au cours de ce travail, l'exploration d'une nouvelle méthodologie pour la fonctionnalisation d'alcènes non-activés par voie organophotocatalytique a été étudiée. Les oléfines représentent une grande classe de composés chimiques. De nombreuses méthodes ont été développées pour la fonctionnalisation d'alcènes activés. Cependant, la fonctionnalisation des alcènes non-activés reste un challenge synthétique. Par conséquent, développer de nouveaux outils synthétiques pour résoudre ce problème reste un défi pour les chimistes organiciens
The PhD work focuses on the development of new bifunctional chiral organocatalysts and their applications in asymmetric organocatalysis. For this purpose, we first studied the design and synthesis of new chiral organocatalysts possessing an iminophosphorane function, on the one hand, and a hydrogen bond donor function, on the other hand. Thus, several families of bifunctional chiral organocatalysts based on L-proline and (S)-pyroglutamic acid have been synthesized in a few steps with moderate to good overall yields. These new catalysts were subsequently evaluated in various asymmetric reactions. The great potential of these catalysts has been demonstrated in the synthesis of α-acyloxythioester through enantioselective acyl transfer /protonation of α-acyloxy-β-ketosulfides. Very good yields (up to 94%) and enantioselectivities (up to 98%) were obtained. The best performing catalyst was then immobilized on a resin support and evaluated in the same reaction. Generally speaking, the reactions worked well leading to the formation of the expected products in good yields and enantioselectivity. During this work, the exploration of a new methodology for the functionalization of non-activated alkenes by organophotocatalytic route was studied. Olefins represent a large class of chemical compounds. Several methods have been developed for the functionalization of activated alkenes. However, the functionalization of non-activated alkenes remains a synthetic challenge. Therefore, developing new synthetic tools to solve this problem remains a challenge for organic chemists

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Isik, Murat. „Chiral 2-aminodmap/sulfonamides And Squaramides Asbifunctional Acid/base Organocatalysts In Asymmetriccatalysis“. Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613444/index.pdf.

Der volle Inhalt der Quelle

Annotation:

Synthesis and evaluation of catalytic performances of novel bifunctional 2- aminoDMAP-Thiourea/ Sulfonamide/ Squaramide organocatalysts derived from trans-(R,R)-cyclohexane-1,2-diamine forms the main goal of this thesis. For this purpose, direct selective mono-N-pyridilization of trans-(R,R)-cyclohexane-1,2- diamine via Pd and Cu catalysis is described successfully first. Facile preparation of chiral 2-aminoDMAP core catalaphore led to the development of various 2- aminoDMAP- Thiourea/ Sulfonamides/ Squaramides as bifunctional acid/base organocatalyst libraries (most in two-steps overall) which showed good results in asymmetric conjugate addition of 1,3-dicarbonyls to trans-(&beta
)-nitrostyrene. Enantiomeric excesses (ee) up to 93% were attained.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Chassillan, Louis. „New Chiral Bifunctional Organocatalysts : Synthesis and Application in Enantioselective Reactions Under Batch and Continuous-Flow Conditions“. Thesis, université Paris-Saclay, 2022. http://www.theses.fr/2022UPASF027.

Der volle Inhalt der Quelle

Annotation:

Au cours des dernières années, l’organocatalyse asymétrique a connu un engouement sans précédent et de nombreux catalyseurs organiques ont été synthétisés dans le but d’effectuer des réactions plus rapides et plus sélectives. Cependant, étant donné la demande croissante de molécules chirales dans l’industrie, il demeure crucial de développer de nouveaux outils afin de rendre leur production plus efficace. Pour ce faire, l’utilisation de la catalyse bifonctionnelle apparait comme une évidence du fait de sa capacité à activer simultanément le nucléophile et l’électrophile et ainsi permettre un meilleur contrôle de la sélectivité. De plus, au cours des dernières années, le recyclage des catalyseurs est devenu une préoccupation importante. En effet, recycler les catalyseurs permet de réduire les coûts liés à l’extraction, au transport ou encore au traitement de ces derniers. C’est pourquoi, l’hétérogénéisation des catalyseurs chiraux semble être une approche attractive pour les applications industrielles. Nous avons donc décidé de concentrer nos efforts sur la synthèse de nouveaux catalyseurs organiques bifonctionnels homogènes et hétérogènes afin d’effectuer la synthèse de composés chiraux en batch et en flux-continu. Dans un premier temps, de nouveaux catalyseurs guanidine-thiourées ont été synthétisés et utilisés avec succès pour la réaction d’hydrophosphonylation asymétrique d’imines et l’addition-1,4 de malonates sur le trans-β-nitrostyrène. Dans un second temps le catalyseur le plus performant a été hétérogénéisé par polymérisation avec du styrène et utilisé pour la réaction d’hydrophosphonylation asymétrique d’imines en flux-continu. Enfin, de nouveaux catalyseurs de type proline-amide ont aussi été préparés et leurs efficacités ont été évaluées dans la réaction d’aldolisation entre l’acétone et la trifluoro acétophénone
Asymmetric organocatalysis field has known an important expansion in the past years and powerful synthetic tools have been developed to perform fast and selective reactions. However, regarding the increasing use of chiral molecules and drugs in the industry, especially in pharmaceutical industry, it is crucial to design new catalysts in order to synthesize valuable chiral molecules in a more efficient manner. For that, bifunctional organocatalysts appear to be an efficient approach as the synergistic activation of nucleophile and electrophile usually allows better control of the selectivity and shorter reaction times. Moreover, the reusability of catalysts has become a major concern in the recent years as recycling allows a significant reduction in resources commonly associated with extraction or transportation and processing of industrial catalysts. Therefore, the heterogenization of chiral catalysts seems to be a very attractive approach for industrial applications. Considering all those concerns, we decided to focus on synthesizing novel chiral bifunctional catalysts and heterogenizing them to perform heterogeneous catalysis under batch and continuous-flow conditions. In the first part, guanidine-thiourea catalysts were successfully synthesized and applied for the enantioselective hydrophosphonylation reaction of imines providing a large scope of α-amino phosphonates with high yields and high ee. The 1,4-Michael addition of malonates to trans-β-nitrostyrene was also investigated. In the second part, the newly synthesized guanidine-thiourea catalysts were heterogenized by polymerization with styrene and the resulting polymer was used for the asymmetric Pudovik reaction under continuous-flow conditions. Finally, new prolineamide catalysts were synthesized in the last part and their efficiency for the aldol reaction of trifluoro acetophenone and acetone was investigated

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Lishchynskyi, Anton. „Development of new methods for the asymmetric formation of C-N bonds“. Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAF026.

Der volle Inhalt der Quelle

Annotation:

Au cours de ce travail de nouvelles méthodes pour la formation de liaison C-N ont été développées. Dans la première partie de cette thèse une application de catalyse métal-ligand bifonctionnelle pour la réaction énantiosélective aza-Michael est démontrée. Dans la deuxième partie nous présentons le travail sur les cyclisations, en utilisant des alcaloïdes du quinquina facilement disponibles, comme catalyseurs des plus prometteurs, fournissant des β-amino-acides d’indoline avec jusqu'à 98% ee. Parmi eux, l’hydroquinidine ressort du lot comme étant le catalyseur donnant le meilleur excès énatiomérique. La troisième partie est liée à l'élaboration d'un nouveau processus intermoléculaires de diamination de styrènes, diènes et triènes, utilisant des bis-sulfonylimides comme source d'azote, en combinaison avec le diacétate de iodosobenzène, qui fournit une approche intéressante et efficace de diamines vicinales biologiquement et chimiquement important. La réaction peut être effectuée à température ambiante sans avoir besoin de protection par atmosphère inerte
The concept of metal-ligand bifunctionality was successfully applied for an enantioselective aza-Michael reaction by employing well-defined ruthenium amido complexes. The catalyst was optimised and the corresponding chiral indoline β-amino acid derivatives were obtained with high enantioselectivities. Next, a straightforward enantioselective bifunctional organocatalytic approach was also developed. Employing hydroquinidine as catalyst the corresponding cyclic products were obtained in excellent enantioselectivities and quantitative yields. These compounds can be selectively deprotected and applied to peptide synthesis. Finally, we have developed unprecedented diamination reactions of styrenes, butadienes and hexatrienes employing easily accessible hypervalent iodine(III) reagents under robust reaction conditions. The first examples of the metal-free 1,2-diamination of butadienes were demonstrated and this oxidation methodology was further extended to the highly attractive 1,4 installation of two nitrogen atoms within a single step

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Yalalov, Denis. „Bifunctional Thiourea-Based Organocatalysts for Asymmetric C-C Bond Formation Reactions: Strecker, Nitro-Michael, Mannich“. Doctoral thesis, 2007. http://hdl.handle.net/11858/00-1735-0000-0006-ACA2-6.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Buchteile zum Thema "Bifunctional chiral catalysts"

Pápai, I. „Bifunctional Catalysis by Chiral Amines“. In Brønsted Base and Acid Catalysts, and Additional Topics, 1. Georg Thieme Verlag KG, 2012. http://dx.doi.org/10.1055/sos-sd-205-00469.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Gouverneur, V., und O. Lozano. „Asymmetric Fluorination with Chiral Bifunctional Phase-Transfer Catalysts“. In Stereoselective Pericyclic Reactions, Cross Coupling, and C—H and C—X Activation, 1. Georg Thieme Verlag KG, 2011. http://dx.doi.org/10.1055/sos-sd-203-00570.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Hatakeyama, S. „Using Chiral Bifunctional 2′-Phosphino-1,1′-binaphthalen-2-ol-Based Catalysts“. In Lewis Base and Acid Catalysts, 1. Georg Thieme Verlag KG, 2012. http://dx.doi.org/10.1055/sos-sd-204-00355.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Hatakeyama, S. „Using A Chiral Bifunctional 1,1′-Bi-2-naphthol-Derived Aryldiphenylphosphine Catalyst“. In Lewis Base and Acid Catalysts, 1. Georg Thieme Verlag KG, 2012. http://dx.doi.org/10.1055/sos-sd-204-00357.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Hatakeyama, S. „Using Chiral Bifunctional and Trifunctional 2′-Phosphino-1,1′-binaphthalen-2-amine-Based Catalysts“. In Lewis Base and Acid Catalysts, 1. Georg Thieme Verlag KG, 2012. http://dx.doi.org/10.1055/sos-sd-204-00356.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Ward, Robert S. „Allyl compounds“. In Bifunctional Compounds. Oxford University Press, 1994. http://dx.doi.org/10.1093/hesc/9780198558088.003.0009.

Der volle Inhalt der Quelle

Annotation:

This chapter focuses on allyl alcohols, which are renowned for their ease of oxidation. It refers to manganese dioxide, which is highly effective for bringing about the oxidation of primary allylic alcohols to the αβ-unsaturated aldehydes. It also describes a highly-selective oxidation of allylic alcohols that involves epoxidation of the carbon-carbon double bond using tert-butyl hydroperoxide and a titanium or vanadium catalyst. The chapter analyses a valuable method of asymmetric synthesis known as Sharpless epoxidation, which involves treating the allylic alcohol with tert-butyl hydroperoxide in the presence of titanium tetraisopropoxide and a chiral ester of tartaric acid. This produces epoxy alcohols, which can be converted into a wide variety of other products by reduction or nucleophilic addition. The chapter also covers allyl ethers and allyl halides.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Lambert, Tristan H. „Construction of Single Stereocenters“. In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0031.

Der volle Inhalt der Quelle

Annotation:

Haifeng Du at the Chinese Academy of Sciences reported (J. Am. Chem. Soc. 2013, 135, 6810) the borane-catalyzed asymmetric hydrogenation of imine 1 to 2 using the diene 3 as a chiral ligand for boron. A single-enzyme cascade for the reductive transamination of acetophenone 4 with amine 5 to produce enantiopure sec-phenethylamine 6 was developed (Chem. Commun. 2013, 49, 161) by Per Berglund at the KTH Royal Institute of Technology in Sweden. A group at Boehringer Ingelheim in Ridgefield, Connecticut, led by Jonathan T. Reeves, disclosed (J. Am. Chem. Soc. 2013, 135, 5565) a procedure for the addition of DMF anion to N-sulfinyl imine 7 to furnish tert-leucine amide 8 with high diastereoselectivity. The tertiary carbinamine 10 was synthesized (Org. Lett. 2013, 15, 34) via the carbolithiation/rearrangement of vinylurea 9 as reported by Jonathan Clayden at the University of Manchester. Gregory C. Fu at Caltech reported (Angew. Chem. Int. Ed. 2013, 52, 2525) that the chiral phosphine 12 catalyzed the enantioselective addition of trifluoroacetamide to allene 11 to produce γ-amino ester 13 in enantioenriched form. Adeline Vallribera at the Autonomous University of Barcelona found (Org. Lett. 2013, 15, 1448) that a europium pybox complex effected the highly enantioselective α-amination of β-ketoester 14 to generate 15 on the way to the Parkinson’s disease co-drug L-carbidopa. Hisashi Yamamoto at the University of Chicago and Chubu University reported (J. Am. Chem. Soc. 2013, 135, 3411) that a halfnium(IV) complex of the bishydroxamic acid 17 catalyzed the enantioselective epoxidation of the tertiary homoallylic alcohol 16 to 18. The rearrangement of the allylic carbonate 19 to produce allyl ether 21 with high ee under iridium catalysis in the presence of ligand 20 was disclosed (Org. Lett. 2013, 15, 512) by Hyunsoo Han at the University of Texas, San Antonio. The asymmetric vinylogous aldol reaction of 3-methyl-2-cyclohexen-1-one 22 and α-keto ester 23 to furnish tertiary carbinol 25 using the bifunctional catalyst 24 was developed (Org. Lett. 2013, 15, 220) by Paolo Melchiorre at ICREA and ICIQ in Spain.

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Liu, Yanyong, Toshiaki Hanaoka, Kazuhisa Murata und Kinya Sakanishi. „Hydroisomerization and hydrocracking of long chain n-alkane and Fischer-Tropsch wax over bifunctional Pt-promoted Al-HMS catalysts“. In Recent Progress in Mesostructured Materials - Proceedings of the 5th International Mesostructured Materials Symposium (IMMS2006), Shanghai, P.R. China, August 5-7, 2006, 781–85. Elsevier, 2007. http://dx.doi.org/10.1016/s0167-2991(07)80436-8.

Der volle Inhalt der Quelle

APA, Harvard, Vancouver, ISO und andere Zitierweisen

Wir bieten Rabatte auf alle Premium-Pläne für Autoren, deren Werke in thematische Literatursammlungen aufgenommen wurden. Kontaktieren Sie uns, um einen einzigartigen Promo-Code zu erhalten!