Transition Metal-Mediated Synthesis and Functionalization of Macrocycles

Transition Metal-Mediated Synthesis and Functionalization of Macrocycles PDF Author: Sedef Karabiyikoglu
Publisher:
ISBN:
Category :
Languages : en
Pages : 391

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Book Description
Transition metal-mediated synthesis and functionalization of macrocycles were investigated. A novel synthetic strategy was discovered to build macrocyclic enynes; vic-dibromo tetrasubstituted alkenes were utilized as highly effective protected alkyne groups in selective ene-ene ring closing metathesis reactions of (E)-dibromotrienes. Macrocyclic enynes with varied sizes and functionality were synthesized in excellent yields by facile Zn-promoted deprotection of (E)-dibromodiene rings. The new strategy circumvented high catalyst loadings and reaction condition restrictions; thus, was proven superior to traditional alkyne protection methods employing dicobalt octacarbonyl complexations. Cyclic enynes were obtained in a more step-economic and efficient manner compared to classical SN2 ring closing processes. The reactivity and utility of enyne rings were showcased by platinum(II)-catalyzed transannular cyclopropanations. The first dicobalt hexacarbonyl-promoted transannular [4+2] cycloaddition reactions were demonstrated. Optimized cycloadditions for macrocyclic dicobalt-dienyne complexes afforded target tricyclic scaffolds in a more effective manner than thermal transannular Diels-Alder reactions of metal-free dienyne rings. Further, dicobalt hexacarbonyl complexes of unactivated dienophiles underwent intermolecular room temperature-[4+2] cycloadditions with unactivated dienes leading to products that are inaccessible by thermal Diels-Alder reactions. Cycloaddition reactions of complexes were highly selective; [4+2] reaction adducts were obtained stereospecifically and competing Pauson-Khand reactions were not detected. Functionalizations of enyne macrocycles through intermolecular and transannular reactions of their corresponding dicobalt complexes were studied. Novel complex polycycles were prepared by intramolecular and intermolecular [2+2+2], [2+2+1+1], [2+2+1] cycloadditions. The chemoselectivity of dicobalt-promoted cycloadditions was altered by varying the promoter and solvents utilized. The first transannular Pauson-Khand reaction was discovered. The novel synthetic method was optimized and structural requirements for reaction substrates were investigated.

Transition Metal-Mediated Synthesis and Functionalization of Macrocycles

Transition Metal-Mediated Synthesis and Functionalization of Macrocycles PDF Author: Sedef Karabiyikoglu
Publisher:
ISBN:
Category :
Languages : en
Pages : 391

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Book Description
Transition metal-mediated synthesis and functionalization of macrocycles were investigated. A novel synthetic strategy was discovered to build macrocyclic enynes; vic-dibromo tetrasubstituted alkenes were utilized as highly effective protected alkyne groups in selective ene-ene ring closing metathesis reactions of (E)-dibromotrienes. Macrocyclic enynes with varied sizes and functionality were synthesized in excellent yields by facile Zn-promoted deprotection of (E)-dibromodiene rings. The new strategy circumvented high catalyst loadings and reaction condition restrictions; thus, was proven superior to traditional alkyne protection methods employing dicobalt octacarbonyl complexations. Cyclic enynes were obtained in a more step-economic and efficient manner compared to classical SN2 ring closing processes. The reactivity and utility of enyne rings were showcased by platinum(II)-catalyzed transannular cyclopropanations. The first dicobalt hexacarbonyl-promoted transannular [4+2] cycloaddition reactions were demonstrated. Optimized cycloadditions for macrocyclic dicobalt-dienyne complexes afforded target tricyclic scaffolds in a more effective manner than thermal transannular Diels-Alder reactions of metal-free dienyne rings. Further, dicobalt hexacarbonyl complexes of unactivated dienophiles underwent intermolecular room temperature-[4+2] cycloadditions with unactivated dienes leading to products that are inaccessible by thermal Diels-Alder reactions. Cycloaddition reactions of complexes were highly selective; [4+2] reaction adducts were obtained stereospecifically and competing Pauson-Khand reactions were not detected. Functionalizations of enyne macrocycles through intermolecular and transannular reactions of their corresponding dicobalt complexes were studied. Novel complex polycycles were prepared by intramolecular and intermolecular [2+2+2], [2+2+1+1], [2+2+1] cycloadditions. The chemoselectivity of dicobalt-promoted cycloadditions was altered by varying the promoter and solvents utilized. The first transannular Pauson-Khand reaction was discovered. The novel synthetic method was optimized and structural requirements for reaction substrates were investigated.

Advances in Transition-Metal Mediated Heterocyclic Synthesis

Advances in Transition-Metal Mediated Heterocyclic Synthesis PDF Author: Daniel Sole
Publisher: Academic Press
ISBN: 0128116528
Category : Science
Languages : en
Pages : 368

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Book Description
Advances in Transition-Metal Mediated Heterocyclic Synthesis provides an overview of recent catalytic reactions involving transition metals to produce heterocyclic compounds. The book is organized according to the type of transformation used to achieve the synthesis of the heterocyclic systems (mainly aza- and oxa-heterocycles). As such, it covers recent applications on the synthesis of heterocycles, also describing the details of the novel transformations in a didactic manner to motivate readers in search of new catalytic processes. The editors have included state-of-the-art strategies, including transition-metal reactions involving unsaturated systems (reactions of allenes, new gold(I)-catalyzed reactions, and Prins reaction). Chapters highlight the versatility of organopalladium chemistry dealing with carbonylative transformations, C-H activation reactions, coupling processes, and the control of the ambiphilic character of organopalladium species. Finally, the book discusses new reactions leading to heterocycles based on C-H activation processes catalyzed by other metals (Rh, Ru, Co). Written by an outstanding team of authors who are leading experts in organometallic chemistry and organic synthesis, this book is a valuable resource not only for chemists mainly focused on synthesis, but also for those interested in reaction mechanisms involving transition metals. - Helpfully organized by transformation type to stimulate the search for new synthetic processes - Completely illustrated and written by global experts - Includes thoughtfully selected strategies chosen by the editors to exemplify the state-of-the-art of the subject, including transition-metal reactions involving unsaturated systems, organopalladium chemistry, and metal-catalyzed C-H activation

Heterocycles from Transition Metal Catalysis

Heterocycles from Transition Metal Catalysis PDF Author: AndrĂ¡s Kotschy
Publisher: Springer Science & Business Media
ISBN: 9781402036248
Category : Science
Languages : en
Pages : 224

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Book Description
"Heterocycles from Transition Metal Catalysis: Formation and Functionalization" provides a concise summary of the prominent role of late transition metal (palladium, nickel, copper) catalysed processes in the synthesis and functionalization of heterocyclic systems. It gives an introduction to catalytic transformations, an overview of the most important reaction types, and presents synthetically useful catalytic processes classified by the target system and the type of transformation. The book provides a representative selection of transition metal catalysed reactions transformations that are relevant in heterocyclic chemistry. In this way, the authors present a useful resource for members of the academic community looking for a textbook as well as industrial chemists in search of a reference book. This book will be an invaluable resource for synthetic chemists, medicinal chemists, and those more generally interested in applied catalysis.

New Pathways for Organic Synthesis

New Pathways for Organic Synthesis PDF Author: H.M. Colquhoun
Publisher: Springer Science & Business Media
ISBN: 1461326516
Category : Science
Languages : en
Pages : 459

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Book Description
The continually growing contribution of transition metal chemistry to synthetic organic chemistry is, of course, widely recognized. Equally well known is the difficulty in keeping up-to-date with the multifarious reactions and procedures that seem to be spawned at an ever-increasing rate. These can certainly be summarized on the basis of reviews under the headings of the individual transition metals. More useful to the bench organic chemist, however, would be the opposite type of concordance based on the structural type of the desired synthetic product. This is the approach taken in the present monograph, which presents for each structural entity a conspectus of the transition metal-mediated processes that can be employed in its production. The resulting comparative survey should be a great help in devising the optimum synthetic approach for a particular goal. It is presented from an essentially practical viewpoint, with detailed direc tions interspersed in the Houben-Weyl style. The wide scope of the volume should certainly encourage synthetic organic chemists to utilize fully the range and versatility of these transition metal-mediated processes. This will certainly be a well-thumbed reference book! R. A. RAPHAEL Cambridge University v Preface In recent years an enormous amount of work has been done on the catalysis of organic reactions by various transition metal species and on the organic reactivity of organo-transition-metal compounds.

Transition Metal Mediated Synthesis of Heterocycles

Transition Metal Mediated Synthesis of Heterocycles PDF Author: Rupert Alexander Hunter
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Transition Metal-Catalyzed Heterocycle Synthesis via C-H Activation

Transition Metal-Catalyzed Heterocycle Synthesis via C-H Activation PDF Author: Xiao-Feng Wu
Publisher: John Wiley & Sons
ISBN: 3527338888
Category : Technology & Engineering
Languages : en
Pages : 596

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Book Description
Reflecting the tremendous growth of this hot topic in recent years, this book covers C-H activation with a focus on heterocycle synthesis. As such, the text provides general mechanistic aspects and gives a comprehensive overview of catalytic reactions in the presence of palladium, rhodium, ruthenium, copper, iron, cobalt, and iridium. The chapters are organized according to the transition metal used and sub-divided by type of heterocycle formed to enable quick access to the synthetic route needed. Chapters on carbonylative synthesis of heterocycles and the application of C-H activation methodology to the synthesis of natural products are also included. Written by an outstanding team of authors, this is a valuable reference for researchers in academia and industry working in the field of organic synthesis, catalysis, natural product synthesis, pharmaceutical chemistry, and crop protection.

Chemoselective and Bioorthogonal Ligation Reactions

Chemoselective and Bioorthogonal Ligation Reactions PDF Author: W. Russ Algar
Publisher: John Wiley & Sons
ISBN: 352768347X
Category : Technology & Engineering
Languages : en
Pages : 923

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Book Description
This timely, one-stop reference is the first on an emerging and interdisciplinary topic. Covering both established and recently developed ligation chemistries, the book is divided into two didactic parts: a section that focuses on the details of bioorthogonal and chemoselective ligation reactions at the level of fundamental organic chemistry, and a section that focuses on applications, particularly in the areas of chemical biology, biomaterials, and bioanalysis, highlighting the capabilities and benefits of the ligation reactions. With chapters authored by outstanding scientists who range from trailblazers in the field to young and emerging leaders, this book on a highly interdisciplinary topic will be of great interest for biochemists, biologists, materials scientists, pharmaceutical chemists, organic chemists, and many others.

Transition Metals in the Synthesis of Complex Organic Molecules

Transition Metals in the Synthesis of Complex Organic Molecules PDF Author: Louis S. Hegedus
Publisher: University Science Books
ISBN: 9781891389047
Category : Science
Languages : en
Pages : 358

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Book Description
This second edition offers easy access to the field of organotransition metal chemistry. The book covers the basics of transition metal chemistry, giving a practical introduction to organotransition reaction mechanisms.

Synthesis and Study of New Macrocycles and Some of Their Transition Metal Complexes

Synthesis and Study of New Macrocycles and Some of Their Transition Metal Complexes PDF Author: Charles James Reader
Publisher:
ISBN:
Category :
Languages : en
Pages : 141

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Book Description


Transition Metal-catalyzed Synthesis and Functionalization of Carbo- and Heterocyles

Transition Metal-catalyzed Synthesis and Functionalization of Carbo- and Heterocyles PDF Author: Natalia Chernyak
Publisher:
ISBN:
Category :
Languages : en
Pages : 760

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Book Description