Дисертації з теми "Borylation reaction"
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1
Palau, Lluch Gerard. "alpha,beta-difunctionalization of alpha,beta-unsaturated carbonyl compounds through borylation reaction." Doctoral thesis, Universitat Rovira i Virgili, 2015. http://hdl.handle.net/10803/311620.
Повний текст джерелаАнотація:
Aquesta tesi presenta resultats referits a noves metodologies aplicades cap a la obtenció de productes alfa-funcionalitzats i beta-borilats, que no tenen precedents en la bibliografia, a partir de cetones alfa,beta-insaturatdes. Les funcionalitzacions estudiades han sigut utilitzant fluor, per obtenir alfa-fluoro beta-boryl cetones; halogens, per obtenir alfa-halo beta-boryl cetones (sent els halogens clor i brom); i finalment difuncionalitzar cetones alfa,beta-insaturades per obtenir alfa-aryl beta-boryl cetones, que tal i com es reporta a la tesi, han sigut els intermedis cap a la sintesi de 2-aryl-1,3-diones, que són productes de sintesis molt valorats en la industria per les seves propietats com a pesticides.
En tots tres casos, s'ha aconseguit la obtenció dels productes difuncionalitzats, dels quals cap havia sigut previament presentat a la bibligrafia existent, concluent per tant que aquest ha sigut un treball pioner cap a la sintesi i obtenció d'aquests compostos difuncionalitzats.Esta tesis presenta los resultados pertenecientes a nuevas metodologias aplicadas hacia la obtención de productos alfa-funcionalizados y beta-borilados que no tienen precedente en la bibliografia, a partir de cetonas alfa,beta-insaturadas. Las funcionalizaciones estudiadas han sido utilizando fluor, para obtener alfa-fluoro beta-boryl cetonas; halogenos, para obtener alfa-halo beta-boril cetonas (siendo los halogenos cloro y bromo); y finalmente la difuncionalización de cetonas alfa,beta-insaturadas para obtener alfa-aryl beta-boryl cetonas, que tal y como se presenta en la tesis, han sido los productos intermedios hacia la sintesi de 2-aryl-1,3-dionas, que són productos de sintesis muy valorados en la indústria por sus propiedades como pesticidas. En todos los tres casos, se consiguió la obtención de los productos difuncionalizados, de los cuales ninguno habia sido previamente presentado en la bibliografia existente, concluyendo que éste ha sido un trabajo pionero hacia la sintesi y obtención de estos compuestos difuncionalizados.
This thesis presents the results concerning new methodologies towards the obtantion of alpha-functionalized beta-borylated compounds from alpha,beta-unsaturated carbonyl compounds, with no precedent in the litherature. The functionalizations studied focused on fluorine, to obtain alpha-fluoro beta-boryl ketones; halogens, to obtain alpha-halo beta-boryl ketones (being the halogens chlorine and bromine); and finally, the difunctionalization of alpha,beta-unsaturated ketones to obtain the corresponding alpha-aryl beta-boryl ketones, which as presented in this thesis, they have been the intermadiates towards the synthesis of 2-aryl-1,3-diones. 2-aryl-1,3-diones are highly valued products in industry for their properties as pesticides. In the three cases studied, we obtained the desired difunctionalized products, which any of them has been previously presented in the existing literature, concluding that this has been a pioneering work towards the synthesis and obtantion of such difunctionalized compounds.
2
Eliseeva, Maria N. "New Route to a [5,5] Carbon Nanotube End-Cap via Direct Borylation of Corannulene." Thesis, Boston College, 2011. http://hdl.handle.net/2345/2752.
Повний текст джерелаАнотація:
Thesis advisor: Lawrence T. ScottThe Scott lab is interested in the functionalization of corannulene as a building block for large polycyclic aromatic hydrocarbons and carbon nanotube end-cap precursors. Toward that end, a new approach to the direct five-fold borylation of corannulene with iridium (I) catalysts via C-H activation has been explored. It has been discovered that the addition of catalytic amounts of base to the reaction mixture promotes the formation of symmetrical penta-borylated corannulene in a good yield on a sizable scale. All byproducts can be easily removed with iterative methanol washes. The present work also provides proof of the reversibility of the direct borylation reaction under the conditions used. Furthermore, modified Suzuki-Miyaura conditions have been employed to synthesize pentakis(2,6-dichlorophenyl)corannulene, a precursor for a [5,5] carbon nanotube end-cap. The reported reactions provide good yields and are scalable
Thesis (MS) — Boston College, 2011
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
3
Sasaki, Ikuo. "Development of Novel Synthetic Methods of Organosilicon Compounds Utilizing Silicon-Containing Reactive Intermediates." Kyoto University, 2020. http://hdl.handle.net/2433/253508.
Повний текст джерела
4
Gallanti, M. "STEREOSELECTIVE SYNTHESIS OF A-AMINO ACIDS B-SUBSTITUTED WITH A 4,5-DIHYDROISOXAZOLE NUCLEUS AND OF TERTIARY AND QUATERNARY ALLYLSILANES." Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/168366.
Повний текст джерелаАнотація:
In the section A of the thesis is presented a stereoselective synthesis of b-hydroxy-a -amino acids b-substituted with a 4,5 dihydroisoxazole nucleus through an aldol type reaction between Schollkopf reagent and isoxazolynil aldehydes and ketones. In the section B is presented the preparation of allyl- or crotylsilane in high dr and er via the lithiation-borylation reaction of alkylcarbamates with silaboronates.The synthesis of quaternary allylsilane through a related strategy is also presented.
5
Larsson, Johanna M. "Transition metal-catalyzed allylic and vinylic functionalization : Method development and mechanistic investigations." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-89524.
Повний текст джерелаАнотація:
The use of small molecule building blocks in, for example, pharmaceutical research and new material development, creates a need for new and improved organic synthesis methods. The use of transition metals as mediators and catalysts opens up new reaction pathways that have made the synthesis of completely new compounds possible as well as greatly improved the synthetic routes to known compounds. Herein, the development of new metal-mediated and catalyzed reactions for construction of vinylic and allylic carbon-carbon and carbon-heteroatom bonds is described. The use of iodonium salts as coupling partners in Pd-catalyzed Heck type reactions with alkenes is shown to improve the current substrate scope. Results from a mechanistic study indicate that the reaction proceeds via high oxidation state palladium intermediates. The use of IIII reagents is also believed to facilitate a PdII/PdIV catalytic cycle in allylic silylation of alkenes using (SiMe3)2, which, to the best of our knowledge, is the first method developed for metal-catalyzed allylic C-H silylation. The same silyl-source, (SiMe3)2, has previously been used in a Pd-catalyzed allylic substitution reaction in which allylic silanes are formed from allylic alcohols. A detailed mechanistic investigation of this reaction is described in which by-products as well as intermediates, including the resting state of the catalyst, are identified using 1H, 11B, 19F and 29Si NMR spectroscopy. Kinetic experiments are performed that give information about the turn-over limiting step and the mechanism of the analogous borylation using B2pin2 is also investigated. Insights from this study further made it possible to improve the stereoselectivity of this reaction. Additionally, a new method for Cu-mediated trifluoromethylation of allylic halides is presented in which linear products are formed exclusively from both linear and branched allylic substrates at room temperature. Identification of allylic fluorides as by-products during the reaction also led to the development of a similar Cu-mediated reaction for the fluorination of allylic halides.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.
6
Yu, Zhiyong. "Total Synthesis of (+)-Discodermolide by Catalytic Stereoselective Borylation Reactions." Thesis, Boston College, 2014. http://hdl.handle.net/2345/bc-ir:103737.
Повний текст джерелаАнотація:
Thesis advisor: James P. Morken(+)-Discodermolide is a marine natural product and is one of the most potent microtubule stabilizers in human cell lines. Because of its unique linear structure and important properties, a number of total syntheses of (+)-discodermolide and its derivatives have been reported. Herein, an efficient, highly convergent, and stereocontrolled total synthesis is presented (Chapter 2). The synthesis relied on the development of three catalytic and stereoselective processes: platinum-catalyzed asymmetric diene diboration, nickel-catalyzed diastereoselective hydroboration of chiral dienes (Chapter 1), and nickel-catalyzed borylative diene-aldehyde coupling (see Chapter 4). Combination of these reactions allows preparation of the target in a short sequence. Moreover, the development of rhodium-catalyzed asymmetric hydroformylation (Chapter 3) makes this approach the first Roche ester free (+)-discodermolide synthesis
Thesis (PhD) — Boston College, 2014
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
7
Xu, Conghui. "Rhodium-mediated Activation and Borylation Reactions of Fluorinated Olefins." Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/22174.
Повний текст джерелаАнотація:
Die Dissertation beinhaltet Studien zur Reaktivität von Rhodiumkomplexen gegenüber unterschiedlichen ungesättigten fluorierten Olefinen mit einem Fokus auf C–F Aktivierungs- und Borylierungsreaktionen.
Der Rhodium(I)hydridokomplex [Rh(H)(PEt3)3] (1) wurde als Katalysator in den Reaktionen von HFO-1234yf, HFO-1234ze, HFO-1225zc bzw. HFO-1225ye (Z) mit HBpin verwendet. Dabei wurden Produktgemische bestehend aus Borylierungsprodukten erhalten. Die selektive Mono- und Dihydroborierung von 3,3,3-Trifluorpropin konnte durch Verwendung von Komplex 1 als Katalysator erreicht werden.
Trifluorethylen konnte durch die Reaktion mit HBpin und Komplex 1 als Katalysator in ein Produktgemisch überführt werden. Stöchiometrische Reaktion zeigen, dass Komplex 1 sowohl unter C–F-Bindungsaktivierung reagiert als auch die Koordination von Trifluorethylen, unter Bildung des Komplexes trans-[Rh(F)(ƞ2-CF2CFH)(PEt3)2], stattfindet. Im Falle von 1,1,2-Trifluorbuten wurde ebenfalls eine C–F-Bindungsaktivierung durch Komplex 1 beobachtet. Mechanistische Untersuchungen der Reaktion von Komplex 1 und 1,1,2-Trifluorbuten bei unterschiedlichen Temperaturen zeigten Hinweise für Koordination & Insertion des Alkens, sowie anschließende β-H-Eliminierung und oxidative C–F-Bindungsadditions- und reduktive HF-Eliminierungsschritte.
Außerdem konnte durch Verwendung von Komplex 1 oder [Rh(Bpin)(PEt3)3] (3) als Katalysator eine stöchiometrische und katalytische Hydroborierung von Pentafluorstyren mit HBpin erreicht werden. Die Rhodium(I)komplexe 1 und 3 sind in der Lage das Olefin zu koordinieren und die C–F-Bindung zu aktivieren, während die Verwendung der Verbindung [Rh(Me)(PEt3)3] die C–H-Bindungsaktivierung fördert. Bei 333 K findet die Aktivierung des fluorierten Aromaten in der 4-Stellung statt, während bei Raumtemperatur die Aktivierung in der 2-Stellung bevorzugt ist.The dissertation reports on studies on the reactivity of rhodium complexes towards different fluorinated olefins with a focus on C–F activation steps and borylation reactions. The rhodium(I) hydrido complex [Rh(H)(PEt3)3] (1) was employed as catalyst in the reactions of HFO-1234yf, HFO-1234ze, HFO-1225zc and HFO-1225ye with HBpin. A product mixture consisting of borylation products was obtained. Selective mono and dihydroboration reactions of 3,3,3-trifluoropropyne were achieved by employing complex 1 as the catalyst. Similarly, trifluoroethylene was also converted into a mixture of products by the reaction with HBpin with complex 1 as the catalyst. A stoichiometric reaction of complex 1 resulted in the C–F bond activation as well as a coordination of trifluoroethylene to give complex trans-[Rh(F)(ƞ2-CF2CFH)(PEt3)2]. Furthermore, the C–F bond activation was also realized with complex 1 and 1,1,2-trifluorobutene. Mechanistic investigations of the reaction of complex 1 towards 1,1,2-trifluorobutene at variable temperatures indicated the formation of products of coordination, insertion of the olefin and subsequent β-H elimination, C–F oxidative addition as well as HF reductive elimination steps. Furthermore, when utilizing complex 1 or [Rh(Bpin)(PEt3)3] (3) as catalysts, stoichiometric and catalytic hydroboration reactions of pentafluorostyrene occurred with HBpin. The rhodium(I) complexes 1 and 3 were capable of the coordination of the olefin and a C–F bond activation reaction with pentafluorostyrene, while complex [Rh(Me)(PEt3)3] promoted the C–H bond activation. At 333 K, the activation of the fluorinated aromatic ring occurred at the 4-position, while at room temperature, an activation at the 2-position was preferred.
8
Audi, Hassib. "Synthèse stéréosélective d'aminoacides boronatés et silylés pour le piégeage de fluorures, à visée imagerie médicale." Thesis, Dijon, 2012. http://www.theses.fr/2012DIJOS094.
Повний текст джерелаАнотація:
La synthèse stéréosélective d'une nouvelle classe d'amino acides boronatés est réalisée par réaction de Wittig, puis borylation catalysée par un complexe d'iridium. Des amino esters portant un noyau aromatique en position δ de la chaîne latérale, sont tout d'abord préparés par réaction de Wittig d'un sel de phosphonium dérivé d'amino acide avec l'aldéhyde aromatique correspondant, puis estérification et hydrogénation. La borylation de ces amino esters avec le bis(pinacolato)diborane (B2Pin2) en présence d'un complexe d'iridium comme catalyseur, conduit aux dérivés correspondants boronatés avec des rendements atteignant 74% . Enfin, des dérivés iodés ou trifluoroboratés sont facilement obtenus à partir des amino acides boronatés, par réaction avec Nal ou avec KHF2. L'hydrolyse des trifluoroborates d'amino acides en solution tampon a été étudiée par RMN 19F. Dans le cas des amino esters difluorophényle et thiophényle, ces composés montrent une très bonne stabilité à l'hydrolyse. D'un autre côté, la synthèse stéréosélective d'amino acides silylés est également obtenue par réaction de Wittig du sel de phosphonium dérivé d'amino acide avec le 4-di-t-butylsilanobenzaldéhyde. L'amino acide silylé a été utilisé pour la préparation d'un dipeptide avec un rendement de 80%, puis son dérivé fluorosilane sans racémisation, par réaction avec KF. Le dipeptide fluorosilylé obtenu montre une excellente stabilité à l'hydrolyse après 10 jours. Finalement, la méthode de synthèse mise au point, se révèle très efficace pour la préparation d'amino acides boronatés et silylés, et pour leur application au marquage par l'iode ou les fluoruresThe stereoselective synthesis of new boronato amino acid derivatives, using Wittig and C-H iridium-catalyzed borylation as key step reactions, is described. Firstly, the synthesis of amino ester precursors bearing an aromatic moiety in -position of the lateral chain, was achieved by Wittig reaction of a phosphonium salt derived from amino acid with the corresponding aromatic aldehyde, then esterification and hydrogenation. The reaction of the amino esters with the bis(pinacolato)diborane reagent (B2Pin2) in presence of an iridium complex as catalyst, leads to the corresponding boronato derivatives in yields up to 74 %. Finally, the iodo- or trifluoroborato derivatives were easily prepared from the boronato amino acid by reaction either with NaI or with KHF2. The hydrolysis of the trifluoroborato amino acid derivatives was studied in buffer solution using 19F NMR monitoring. In the case of the difluorophenyl and thiophenyl amino esters, the corresponding trifluoroborates derivatives show good to excellent stability toward hydrolysis. In addition, the stereoselective synthesis of silano amino acid has been developped by Wittig reaction of the phosphonium salt derived from amino acid with the 4-di-t-butylsilanobenzaldehyde. The silano amino acid was used to prepare a dipeptide with 80% yield, and the corresponding fluorosilane derivative without racemization, by reaction with KF. The hydrolysis of the fluorosilylated dipeptide in aqueous media shows an excellent stability, up to 10 days. Finally, this stereoselective synthesis of hetero substituted amino acids, offers a promising tool for the application of the boronated and silyled derivatives to the fluoride labeling
9
Coapes, Richard Benjamin. "Rhodium catalysed borylation reactions via direct and indirect C-H activation." Thesis, Durham University, 2002. http://etheses.dur.ac.uk/4176/.
Повний текст джерелаАнотація:
This thesis describes both direct and indirect C-H activation borylation processes, catalysed by several Rh-based catalyst precursors. Chapter One presents an overview of the processes investigated, namely diboration, dehydrogenative borylation, and direct C-H activation of hydrocarbon substrates, which give borylated species that are of interest to synthetic chemists. The uses of such borylated species are also highlighted. Chapter Two highlights the synthetic procedure for the synthesis of the catalyst precursor [Rh(acac)(C0E)(_2)], which can be used to prepare bis-phosphine catalyst precursors of the form [Rh(acacXP(_2))]- Although a procedure appears in the literature, it is not well cited. Also, this new procedure replaces [Tl(acac)] with [Na(acac)] and hence avoids the use of thallium salts. Chapter Three investigates the reaction of two vinyl(boronate) esters (VBEs) with Bzcat], and a wide array of catalyst precursors, which yield, among other species, the tris(boronate) esters ArCH(_2)C(Bcat)(_3) and ArCH(Bcat)CH(Bcat)(_3); the former results from the addition of both borons of the B(_2) unit to the same carbon atom, and are of interest due to their wide synthetic versatility. Chapter Four investigates the dehydrogenative borylation of alkenes using both HBpin and B2pin2, and several catalyst precursors. Most significantly, this route allows the synthesis of 1,1-disubstituted vinyl(boronate) esters that cannot be made by alkyne hydroboration. Chapter Five investigates the direct C-H activation of benzylic and aromatic hydrogens using the catalyst precursor [Rh(Cl)(N(_2))(P(^i)Pr(_3))(_2)]. This allows the functionalisation of hydrocarbon substrates, which are ubiquitous. Chapter Six investigates the stability of B-chlorocatecholborane to phosphines with the view to a boron analogue of the Heck reaction. In such a reaction, phosphmes would likely be employed on the catalyst. An understanding of the stability of the boron reagent under typical reaction conditions is needed, therefore, in order to prevent degradation of B-chlorocatecholborane, a process that is known for catecholborane.
10
Xu, Conghui [Verfasser]. "Rhodium-mediated Activation and Borylation Reactions of Fluorinated Olefins / Conghui Xu." Berlin : Humboldt-Universität zu Berlin, 2020. http://d-nb.info/1222973480/34.
Повний текст джерела
11
Dang, Li. "Density functional theory studies of copper(I) mediated borylation and carboxylation reactions /." View abstract or full-text, 2010. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202010%20DANG.
Повний текст джерела
12
Yang, Lichen. "Studies on Site-Selective C-H Borylation Reactions of Arenes and Heteroarenes." Kyoto University, 2020. http://hdl.handle.net/2433/253291.
Повний текст джерела
13
Solana, González Jorge. "Copper and iridium conjugate addition : cyclisation processes, domino reactions." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/10471.
Повний текст джерелаАнотація:
Asymmetric conjugate addition of bis(pinacolato)diboron followed by aldol cyclisation of enone diones under the action of a chiral copper catalyst has been developed. This enantioselective process, using a chiral bisphosphine as ligand, allows the formation of bicyclic alcohols with four contiguous stereocentres in high diastero- and enantioselectivity. This catalytic system has been applied to the parallel kinetic resolution of a racemic β- ketoamide. Further functionalization of the bicyclic alcohols synthesised was also possible. A domino addition of arylboronic acids and cyclisation of alkynones via an undescribed iridium 1-4-migration process has been developed. A range of tricyclic compounds using a variety of arylboronic acids have been synthesised in good yields and high diasteroselectivity. The use of chiral bisphosphine ligand together with an iridium salt allows the formation of enantioenriched compounds in moderate yield.
14
Xiao, Lu. "Copper-Catalyzed Borylation of Hemiaminal Ethers and Ruthenium-Catalyzed Tandem Reactions of Nitrogen-Tethered Dienes." Thesis, Boston College, 2016. http://hdl.handle.net/2345/bc-ir:107234.
Повний текст джерелаАнотація:
Thesis advisor: Marc L. SnapperChapter 1 Bisphosphine monoxides have unique coordinating capabilities with transition metals. Several research groups have independently reported transition metal-catalyzed highly stereoselective reactions by using chiral bisphosphine monoxides as the ligands. A review of recent works in this field is provided in this chapter to showcase the features of this class of ligand. Chapter 2 We have developed a copper-catalyzed borylation method to synthesize α-aminoboronic esters, which are biologically interesting molecules in enzyme inhibitions. Employment of hemiaminal ethers as substrates to in situ generate the corresponding aldimines obviated purification of the unstable aldimines and potential imine-enamine tautomerization. By using a chiral bisphosphine monoxide ligand in our copper-catalyzed borylation conditions, we successfully synthesized a variety of enantioenriched alkyl-substituted α-aminoboronic esters in good yields and with good enantioselectivity. Chapter 3 A ruthenium-catalyzed three-step tandem sequence was established to prepare nitrogen-protected 2,3-dihydroxypyrrolidines and 2,3-dihydroxypiperidines. This tandem sequence includes ring-closing metathesis, olefin isomerization and olefin dihydroxylation, and utilizes the second-generation Grubbs’ catalyst as the initial ruthenium precatalyst. Readily accessible nitrogen-tethered dienes were used as the substrates to prepare the heterocyclic compounds in an efficient fashion. Through optimization, we discovered the optimal conditions for ruthenium-catalyzed dihydroxylation of ene-carbamates and ene-sulfonamides, which were the challenging substrates in the previous methods
Thesis (PhD) — Boston College, 2016
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
15
French, Rosalind M. "Asymmetric Lithiation/borylation reactions of secondary Benzylic carbamates in the synthesis of tertiary alcohols." Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528073.
Повний текст джерела
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Eichhorn, Antonius [Verfasser], and Todd B. [Gutachter] Marder. "Copper(I) catalyzed borylation and cross-coupling reactions / Antonius Eichhorn ; Gutachter: Todd B. Marder." Würzburg : Universität Würzburg, 2018. http://d-nb.info/1166054896/34.
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17
Morimoto, Masao. "Development of Highly Efficient Synthetic Reactions Catalyzed by Transition Metals." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188615.
Повний текст джерела
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Kremnev, Jimmy D. "Visible light mediated borylation and [2+2] cycloaddition reactions of Thiazolino Ring Fused 2-Pyridones." Thesis, Umeå universitet, Kemiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-177966.
Повний текст джерела
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Kitano, Masaaki. "Chemistry of meso-Free Subporphyrins." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215329.
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20
Yamamoto, Yutaro. "Studies on Palladium-Catalyzed Reactions of Aryl Chlorides with Lewis Acidic Boron or Organosilicon Reagents." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225430.
Повний текст джерела
21
Cho, Hee Yeon. "Catalytic Borylative Multicomponent Coupling Reactions and Novel Chemistry of Polycyclic Aromatic Hydrocarbons." Thesis, Boston College, 2013. http://hdl.handle.net/2345/3398.
Повний текст джерелаАнотація:
Thesis advisor: Lawrence T. ScottThesis advisor: James P. Morken
Expeditious establishment of molecular complexity in a stereoselective manner is a prominent goal in organic synthesis. In this regard, multicomponent coupling reactions have received substantial attention due to their ability to access complex molecules from simple starting materials in a single step. Chapter 1 is a comprehensive review on catalytic bismetallative multicomponent reactions. The scope of this process in terms of both bismetallic reagents and the pi components are broad enough to be generally applied to more elaborate synthetic sequences. Particularly, contemporary applications of the bismetallative multicomponent coupling reactions, in which high enantio- and/or diastereoselectivities are displayed, have enabled the study of this area to make a significant step forward. Chapter 2 presents nickel-catalyzed coupling reactions of aldehyde, diene, and a diboron reagent in the presence of a trialkyl phosphine ligand. Compared to borylation reactions with one pi-component, these borylative multicomponent reactions (involving two pi components) lead to formation of a new C-C bond between the pi components as well as generation of highly functionalized, stereodefined products. Chapter 3 describes a remarkable turnover in regioselectivity of the borylative multicomponent coupling when PCy3 is replaced with P(SiMe3)3. In particular, the products from the reactions with P(SiMe3)3 feature three contiguous stereocenters and an alpha-chiral allylboronate. The effect of P(SiMe3)3 ligand on the product selectivity is intriguing. According to the experimental and computational results, it has an ability to act as an electron acceptor, which will facilitate reductive elimination from the intermediate nickel complex during the course of the reaction. In Chapter 4, we show that borylative ketone-diene coupling reactions can be accomplished in high yields and with excellent levels of diastereocontrol. This reaction occurs in a predictable fashion, yet with regioselection that is distinct from related aldehyde-diene coupling reactions. The reaction products from these coupling processes, which possess tertiary alcohol functionality and an allylic alcohol moiety, are particularly well suited for the preparation of polyketide natural products. Chapter 5 presents investigations on bowl-shaped geodesic polyarenes, which are the missing links between the "classic" planar polycyclic aromatic hydrocarbons (PAHs) and the spheroidal fullerenes. The present study has shown that open geodesic polyarenes can feature chemistry inherent to both classes of aromatics. The curved pi system induces unequal environments on the two faces of circumtrindene, significant strain energy to the molecule, and non-identical bond lengths. Along with the electronic effects, the stereoelectronic effect enabled the site-selective functionalization with fullerene-type chemistry. On the other hand, the edge carbons, which are not present in fullerenes, still possess reactivity of common planar PAHs. Chapter 6 describes the intermolecular oxidative cyclotrimerization reactions of alkenes and aromatic compounds with DDQ and trifluoromethanesulfonic acid. The Scholl-type oxidation reactions involving alkenes have never been demonstrated. Moreover, the DDQ/acid system has never been used for the intermolecular oxidative cyclization reactions. This convenient non-metallic reagent system (DDQ/TfOH) is advantageous over the metal-based Scholl-type oxidants because it eliminates the possibility of halogenation of aromatic compounds and the reduced oxidant can be reoxidized. In Chapter 7, the regioselective formation of cyclic trimers from substituted benzenes and heteroaromatic compounds is demonstrated. This DDQ/TfOH method provides a simple and convenient synthetic route toward star-shaped oligomers containing triphenylene or isotruxene cores. Furthermore, the experimental outcome suggests that this oxidative process proceeds by an electron transfer mechanism. This is the first experimental evidence for mechanistic details on the Scholl-type oxidation
Thesis (PhD) — Boston College, 2013
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Eck, Martin [Verfasser], Todd B. [Gutachter] Marder, Udo [Gutachter] Radius, and Matthias [Gutachter] Lehmann. "Iron- and Copper-catalyzed Borylation of Alkyl and Aryl Halides and B–B Bond Activation and NHC Ring-expansion Reactions of the Diboron(4) Compound Bis(ethylene glycolato)diboron (B\(_2\)eg\(_2\)) / Martin Eck ; Gutachter: Todd B. Marder, Udo Radius, Matthias Lehmann." Würzburg : Universität Würzburg, 2018. http://d-nb.info/1160876975/34.
Повний текст джерела
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Chou, Chun-Chin, and 周俊欽. "Borylation and Suzuki Reaction Catalyzed by NS-MCM-41-Pd and its One-Pot Application." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/9gqx7d.
Повний текст джерелаАнотація:
碩士國立臺北科技大學
有機高分子研究所
95
ABSTRACT Title：Borylation and Suzuki coupling catalyzed by NS-MCM-41-Pd and its One-pot application Pages：89 School：National Taipei University of Technology Department：Institute of Organic and Polymeric Materials Time：July, 2007 Degree：Master Researcher：Chun-Chin Chou Advisor:Fu-Yu Tsai Keywords：suzuki coupling, mesoporous material, palladium complex The use of transition metal as a catalyst plays an important role in organic synthesis in modern industry. Generally, homogeneous catalysts could get better yields under mild conditions, but difficult to be separated from the reaction mixtures after reaction finishing and the residue of the catalyst may destroy the purity and characteristics of the products. On the other hand, heterogeneous catalysts could be easily recovered by simple separation after reaction done and reuse for the next reaction. Herein, we utilized nanosized mesoporous silica materials, NS-MCM-41 (nano-sized MCM-41), as an inorganic solid support and grafting the bipyridyl palladium complex onto the wall to be a heterogeneous catalyst. The physical properties of this material is steady and the worm-hole like structure of the channels enables reactants, salts and products could easily through-out the channels without blockade. Since there is large surface area (around 588 m2/g) inside the channels and the surface has a plenty of silanol group, we can modify complex include catalyst onto NS-MCM-41 by physic adsorption or chemical bonding. This thesis reports that the employment of NS-MCM-41-Pd in the formation of arylboronates and then these products are used as reactants for Suzuki coupling for its one-pot application. The content is composed of two parts: in the first part, we use NS-MCM-41-Pd as a catalyst that is applied on the borylation of aryl halides and pinacolborane; and in the second part, NS-MCM-41-Pd system is employed for Suzuki coupling of aryl halides and arylboronates. Finally, we directly try to proceed one-pot borylation/Suzuki coupling (BSC) reaction. The detail of the activities, recycled properties and leach out studies of NS-MCM-41-Pd for these reactions are discussed in this thesis.
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Verma, Piyush Kumar. "Cobalt-nhc Complexes and Diazabutadienes in Activation of Mono/Diboron Compounds and Their Application in C-b Coupling Reactions." Thesis, 2021. https://etd.iisc.ac.in/handle/2005/5241.
Повний текст джерелаАнотація:
Boronic acid(esters) have been well recognized as an indispensable coupling partner in the Suzuki-Miyaura cross coupling reactions producing a vast spectrum of molecules, applicable in the diverse field ranging from medicinal to materials sciences.[1] Transition metal catalyzed synthesis of boronic esters from diborons with the assistance of bases is a well-established methodology[2]. In this thesis, the cobalt-N-Heterocyclic carbene complexes catalyzed borylation of organic compounds and interaction of diazabutadienes with diboron compounds will be discussed.
(i) In the first section, Co(IMes)2Cl2 catalyzed borylation of aryl halides will be discussed. [3a] The robust protocol, operating under mild condition facilitate the borylation of a diverse range of aryl halides with great efficacy, which includes the challenging aryl chlorides. The preliminary mechanistic studies suggest that base-bis(pinacolato)diboron adduct reduces the Co(IMes)2Cl2 complex to generate Co(IMes)2Cl complex, which acts as an active catalytic species.
(ii) The second section deals with catalytic synthesis of primary and secondary alkyl boronic esters using alkyl halides. [3b] The in situ generated Co-NHC complex, in assistance with base and diboron compound, produces the corresponding borylated product from alky halides. The reaction proceeds under very mild conditions and covers a wide range of alkyl halides, including chlorides having different functional groups.
(iii) In the third section, development in selective hydroboration of vinyl arenes and aliphatic alkenes will be discussed. [3c] Catalyzed by Co(I)NHC complex, the alkene hydroboration by pinacol borane gives Markovnikov selective product with good selectivity, where the regio-selectivity is controlled by phenyl substituent. In absence of that, complete inversion in the selectivity has been observed. The preliminary mechanistic cycle suggests that the catalytic cycle proceeds via oxidative addition of pinacol borane to [Co] followed by alkene insertion and reduction elimination steps.
(iv) The last section discusses the interaction of diazabutadiene molecules with diboron compounds. [3d] The diazabutadiene derivatives have been observed to completely cleave the B-B bond of Bis(catacolato)diboron and Bis(dithiocatacolato)diboron. The preliminary findings hint towards homolytic cleavage of the B-B bond by concerted interaction of the two nitrogen atoms of diazabutadiene with the two boron atoms of the diboron from the same face.
References:
[1] Boronic Acids-Preparation and Applications in Organic Synthesis, Medicine and Materials, 2nd ed.; Hall, D. G., Ed.; Wiley-VCH: Weinheim, 2011.
[2] Neeve, E. C.; Geier, S. J.; Mkhalid, I. A. I.; Westcott, S. A.; Marder, T. B. Diboron(4) Compounds: From Structural Curiosity to Synthetic Workhorse. Chem. Rev. 2016, 116, 9091-9161.
[3] (a) Verma, P. K.; Mandal, S.; Geetharani, K. ACS Catal. 2018, 8, 4049-4054. (b) Verma, P. K.; Prasad, K. S.; Varghese, D.; Geetharani, K. Org. Lett. 2020, 22, 4, 1431-1436. (c) Verma, P. K.; Setulekshmi, A. S.; Geetharani, K. Org. Lett. 2018, 20, 7840-7845. (d) Verma, P. K.; Meher, N. K.; Geetharani, K. Accepted for publication in Chem. Commun., Manuscript ID: CC-COM-06-2021-002881.R2.
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Eichhorn, Antonius. "Copper(I) catalyzed borylation and cross-coupling reactions." Doctoral thesis, 2018. https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-167332.
Повний текст джерелаАнотація:
The present thesis comprises synthesis and stoichiometric model reactions of well-defined NHC-stabilized copper(I) complexes (NHC = N-heterocyclic carbene) in order to understand their basic reactivity in borylation and cross-coupling reactions. This also includes the investigations of the reactivity of the ligands used (NHCs and CaaCs = cyclic alkyl(amino)carbenes) with the substrates, i.e. diboron(4) esters and arylboronates, which are addressed in the second part of the thesisDie dargelegte Arbeit gliedert sich in zwei Teile. In einem ersten wird die Synthese sowie stöchiometrische Modell-Reaktionen von definierten NHC-stabilisierten Kupfer(I)-Komplexen (NHC = N-heterocyclisches Carben) untersucht, um Einblick in das grundlegende Reaktionsverhalten in Borylierungs- und Kreuzkupplungsreaktionen zu erlangen. Der zweite Teil adressiert die Reaktivität der eingesetzten Liganden (NHCs und CaaCs = cyclische Alkyl Amino Carbene) gegenüber verwendeten sowie möglichen Substraten (Arylboronsäureester und Diboran(4)-Verbindungen)
26
Eck, Martin. "Iron- and Copper-catalyzed Borylation of Alkyl and Aryl Halides and B–B Bond Activation and NHC Ring-expansion Reactions of the Diboron(4) Compound Bis(ethylene glycolato)diboron (B\(_2\)eg\(_2\))." Doctoral thesis, 2018. https://nbn-resolving.org/urn:nbn:de:bvb:20-opus-149791.
Повний текст джерелаАнотація:
The purpose of the present work was, in the first part, to investigate the potential of iron-based metal complexes in catalytic borylation reactions with alkyl halides as substrates and B2pin2 as the borylation reagent. Moreover, extended studies of the recently reported, copper mediated borylation reactions of aryl halides were performed, including the screening of substrates and alkoxy bases as well as ligand-screening. Investigations were undertaken on the role of Cu-nanoparticles, which might be involved in this catalytic reaction. Furthermore, Cu-phosphine complexes were synthesized as precursors, but attempts to isolate Cu-boryl species which are intermediates in the proposed catalytic cycle were unsuccessful, although 11B NMR evidence for a Cu-boryl complex was obtained. In the second part of this work, the alternative, Lewis-acidic diboron(4) compound bis(ethylene glycolato)diboron (B2eg2) was synthesized to compare its reactivity with the reactivity of other diboron(4) compounds (e.g. B2neop2, B2cat2, B2pin2 and B2(NMe2)4). Therefore, reactions of B2eg2 with different Lewis-bases, such as NHCs and phosphines, were performed to investigate the possible formation of sp2-sp3 or sp3-sp3 adducts and ring-expansion reactions (RERs). The aim was to obtain a better general insight into the reactivity of diboron(4) compounds with Lewis-bases because they are both used as reactants in transition metal-catalyzed and metal-free borylation reactions. Understanding the B–B bond activation process promoted by Lewis-bases provides a new perspective on the reaction pathways available for various borylation reactionsIm ersten Teil der vorliegenden Arbeit wurde das Potential eisenkatalysierter Borylierungsreaktionen von Alkylhalogeniden (Substrate) mit B2pin2 als Borylierungsreagenz untersucht. Weiterhin wurden detaillierte und intensive Untersuchungen zur literaturbekannten kupferkatalysierten Borylierung von Arylhalogeniden durchgeführt, einschließlich eines Screenings von unterschiedlich funktionalisierten Substraten und diversen Alkoxybasen. Es wurde ebenfalls ein sehr umfangreiches Ligandenscreening durchgeführt. Des Weiteren wurden die mögliche Entstehung und der mögliche Einfluss von Kupfernanopartikeln auf die Borylierungsreaktion untersucht. Um Intermediate der kupferkatalysierten Borylierung zu untersuchen wurden Kupferphosphankomplexe als Vorläufermoleküle für die Synthese von Kupferborylkomplexen hergestellt. Aufgrund der sehr hohen Reaktivität gelang es jedoch nicht, die entsprechenden Kupferborylkomplexe zu isolieren und zu charakterisieren. Es gelang allerdings in einem in situ 11B{1H}-NMR-Experiment, ein 11B{1H}-Signal zu detektieren, welches in dem zu erwartendem Bereich für einen Kupferborylkomplex lag und einen ersten Hinweis für die Bildung eines solchen Kupferborylkomplexes lieferte. Im zweiten Teil der vorliegenden Arbeit wurde das alternative, lewissaure Diboran(4)-Derivat Bis(ethylenglykol)diboran (B2eg2) synthetisiert, um dessen Reaktivität mit der Reaktivität von anderen Diboran(4)-Verbindungen (z.B. B2neop2, B2cat2, B2pin2 und B2(NMe2)4) zu vergleichen. Hierfür wurden Reaktionen von B2eg2 mit unterschiedlichen Lewisbasen wie NHCs und Phosphanliganden durchgeführt und die mögliche Bildung von sp2-sp3 oder sp3-sp3 hybridisierten mono- bzw. bis-Addukten sowie mögliche NHC-Ringerweiterungsreaktionen untersucht. Im Allgemeinen wurde im zweiten Teil der Arbeit versucht ein besseres Verständnis über die Reaktivität von Diboran(4)-Verbindungen mit Lewisbasen zu erlangen, da beide als Reaktanten in übergangsmetallkatalysierten und metallfreien Borylierungsreaktionen verwendet werden. Dies macht es zwingend erforderlich die B–B-Bindungsaktivierung durch Lewisbasen zu verstehen, da hierdurch eine komplett neue Perspektive auf mögliche Reaktionspfade vieler Borylierungsreaktionen eröffnet wird
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(10730742), Henry J. Hamann. "Amine-Boranes: Synthesis and Applications." Thesis, 2021.
Знайти повний текст джерелаАнотація:
Reported herein is a brief summary of the history,
properties, and applications of amine-boranes. The past methods devised for
their preparation are described and the routes used to produce the compounds
used in the work presented here are detailed. Building on prior synthetic
approaches to amine-boranes, a new carbon dioxide mediated synthesis is
presented. Proceeding through a monoacyloxyborane intermediate, the borane
complexes of ammonia, primary, secondary, tertiary, and heteroaromatic amine
are provided in 53-99% yields. Utilizing the amine-boranes obtained from the
methods described, two divergent methods for direct amidation are introduced.
The first uses amine-boranes as dual-purpose reagents, where the carboxylic
acid is first activated by the borane moiety to form a triacyloxyborane-amine
complex. This allows the delivery of the coordinated amine to form the amide
products. A series of primary, secondary, and tertiary amides were prepared in 55-99% yields using this protocol, which
displays a broad functional group tolerance. Extended from this dual-purpose
methodology, a catalytic amidation is described. Utilizing ammonia-borane as a
substoichiometric (10%) catalyst, a series of secondary and tertiary amide are
prepared directly from carboxylic acids and amines in 59-99% yields, including
amines containing typically borane reactive functionalities including alcohols,
thiols, and alkenes. Amine-boranes are additionally used in two borylation
methodologies. By reaction with n-butyl lithium, the amine-boranes are
converted to the corresponding lithium aminoborohydrides, which upon reaction
with a terminal alkyne provides the alkynyl borane-amine complexes in 65-98%
yields. This process is compatible with both alkenes and internal alkynes, as
well as a range of aprotic functionalities. A new strategy for aminoborane
synthesis is also described and applied to the borylation of haloarenes.
Activation of a series of amine-boranes with iodine produces the iodinated
amine-borane, which undergoes dehydrohalogenation with an appropriate base to
produce either monomeric or dimeric aminoboranes. Several aminoboranes were
synthesized exclusively as the monomeric species, which due to their greater
reactivity, were used directly in the synthesis of a series of aryl boronates
in 65-99% yields.