Advances in Late-Metal Carbon-Nitrogen Bond Formation for the Synthesis of Substituted Heterocycles

Advances in Late-Metal Carbon-Nitrogen Bond Formation for the Synthesis of Substituted Heterocycles
Author: Nicolas Rotta-Loria
Publisher:
Total Pages: 0
Release: 2017
Genre:
ISBN:

Late-metal catalyzed cross-couplings have emerged as efficient and selective methodologies for the formation of C-C and C-N bonds. The ability to synthesize complex heterocycles from cheap and abundant starting materials is an invaluable asset to the pharmaceutical industry, given that many pharmaceuticals contain at least one heterocyclic component. This reactivity can be achieved by tuning the steric and electronic properties of ancillary ligands to support metal catalysts in the reaction steps leading to the target substrate. The Stradiotto group has developed several state-of-the-art methodologies involving ligands for palladium catalysis, for both C-C and C-N bond-forming reactions. These methodologies can be amalgamated into a multicomponent reaction platform to synthesize more complex products from simple materials. Chapter 1 outlines this concept with the application of a Mor-DalPhos/Pd catalyst in the one-pot synthesis of indoles from acetone and simple amines involving C-C and C-N bond formation. The robust nature of this method can be extended to include benchtop reaction conditions in a one-step, one-pot synthesis of indoles, thus representing a useful synthetic protocol. While palladium provides a powerful tool for C-C and C-N bond formation, the general trend in catalysis has shifted away from the precious metals toward first row metals as economic alternatives. Nickel complexes have recently emerged as excellent catalysts for a number of amination reactions. The ability to utilize ammonia also represents a sought after reaction, due to the widespread availability and synthetic utility of amino-functionalized products. In this regard, Chapter 2 will focus on the development and application of both commercially available and strategically designed ligand classes for the monoarylation of ammonia with substituted heterocycles. Hydrazine represents an important synthon in synthetic chemistry. It is synthesized on multi-ton scale every year and represents an important building block in many industrial processes. Many synthetic challenges arise from using free hydrazine as reactant, which has led to lethargic growth of its application in the field of late-metal catalyzed C-N bond-formation. However, gold-catalyzed methodologies have been developed utilizing NHC ligands to allow for the hydrohydrazination of alkynes with parent hydrazine. Chapter 4 examines the development and application of a series of (PR3)AuCl complexes for use in such transformations, leading to the identification of the first effective phosphine-bound gold complex for use in the hydrohydrazination of alkynes at room temperature.

Metals and Non-metals

Metals and Non-metals
Author: Navjeet Kaur
Publisher: CRC Press
Total Pages: 404
Release: 2020-01-28
Genre: Science
ISBN: 1000733416

Design of new processes that avoid the use of toxic reagents has been the focus of intense research of late. Catalysis by metals and non-metals offers diverse opportunities for the development of new organic reactions with promising range of selectivities—chemoselectivity, regioselectivity, diastereoselectivity, and enantioselectivity. Furthermore, these transformations frequently occur under mild conditions, tolerate a broad array of functional groups, and proceed with high stereoselectivity. The area of catalysis is sometimes referred to as a ‘foundational pillar’ of green chemistry. Catalytic reactions often reduce energy requirements and decrease separations because of increased selectivity; they are also capable of permitting the use of renewable feedstocks of less toxic reagents or minimizing the quantities of reagents needed. New catalytic organic synthesis methodologies have, thus, offered several possibilities for considerable improvement in the eco-compatibility of fine chemical production. Hence, these catalytic methodologies have emerged as powerful tools for the efficient and chemoselective synthesis of heterocyclic molecules. Key Features: Presents the synthesis of different five-membered heterocycles. Contains the most up-to-date information in this fast-moving field. Covers novel catalytic approaches used in the study and application of catalysts in synthetic organic reactions. Presents new methodologies for the synthesis of heterocycles.

Heterocycles via Cross Dehydrogenative Coupling

Heterocycles via Cross Dehydrogenative Coupling
Author: Ananya Srivastava
Publisher: Springer Nature
Total Pages: 494
Release: 2019-08-23
Genre: Science
ISBN: 9811391440

This book discusses the developments in the synthesis and functionalization of different heterocycles based on the formation of carbon-carbon (C-C) and carbon-heteroatom (C-X) bonds using cross-dehydrogenative coupling (CDC). Consisting of 13 chapters, the book systematically describes the advances in the synthesis and functionalization of nitrogen, oxygen, and sulfur-containing heterocycles. It also discusses the various mechanistic pathways to help readers gain an in-depth understanding of the CDC reactions of heterocycles. Lastly, in order to promote green chemistry, it addresses a range of metal-free CDC reactions of heterocycles – an area that has attracted significant attention in both academic and industrial research.

Catalyzed Carbon-Heteroatom Bond Formation

Catalyzed Carbon-Heteroatom Bond Formation
Author: Andrei K. Yudin
Publisher: John Wiley & Sons
Total Pages: 541
Release: 2010-12-01
Genre: Science
ISBN: 3527633405

Written by an experienced editor widely acclaimed within the scientific community, this book covers everything fromo9xygen to nitrogen functionalities. From the contents: Palladium-Catalyzed Syntheses of Five-Member Saturated Heterocyclic and of Aromatic Heterodynes Palladium-Catalysis for Oxidative 1, 2-Difunctionalization of Alkenes Rhodium-Catalyzed Amination of C-H-Bonds Carbon-Heteroatom Bond Formation by RH(I)-Catalyzed Ring-Opening Reactions Transition Metal-Catalyzed Synthesis of Lactones and of Monocyclic and Fused Five-Membered Aromatic heterocycles the Formation of Carbon-Sulfur and Carbon-Selenium bonds by Substitution and Addition reactions catalyzed by Transition Metal Complexes New Reactions of Copper Acetylides Gold Catalyzed Addition of Nitrogen, Sulfur and Oxygen Nucleophiles to C-C Multiple Bonds. The result is an indispensable source of information for the Strategic Planning of the Synthetic routes for organic, catalytic and medicinal chemists, as well as chemists in industry.

Heterocycles from Transition Metal Catalysis

Heterocycles from Transition Metal Catalysis
Author: András Kotschy
Publisher: Springer Science & Business Media
Total Pages: 224
Release: 2005-09-30
Genre: Science
ISBN: 9781402036248

"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.

Synthesis of Heterocycles via Metal-Catalyzed Reactions that Generate One or More Carbon-Heteroatom Bonds

Synthesis of Heterocycles via Metal-Catalyzed Reactions that Generate One or More Carbon-Heteroatom Bonds
Author: John P. Wolfe
Publisher: Springer
Total Pages: 276
Release: 2013-09-11
Genre: Science
ISBN: 3642388809

Synthesis of Saturated Heterocycles via Metal-Catalyzed Alkene Carboamination or Carboalkoxylation Reactions, by John P. Wolfe Synthesis of Saturated Heterocycles via Metal-Catalyzed Alkene Diamination, Aminoalkoxylation, or Dialkoxylation Reactions, by Sherry R. Chemler Synthesis of Heterocycles via Metal-Catalyzed Wacker-Type Oxidative Cyclization Reactions of Alkoxy- or Amino-Alkenes, by Wanbin Zhang Synthesis of Saturated Heterocycles via Metal-Catalyzed Hydroamination or Hydroalkoxylation Reactions, by Lisa D. Julian Synthesis of Saturated Heterocycles via Metal-Catalyzed Allylic Alkylation Reactions, by Aaron Aponick Synthesis of Heterocycles via Metal-Catalyzed Cascade/Domino Reactions that Generate a C–N or C–O Bond, by Mark Lautens Synthesis of Saturated Heterocycles via Metal-Catalyzed Formal Cycloaddition Reactions that Generate a C–N or C–O Bond, by Jerome Waser

Recent Advances in Synthesizing and Utilizing Nitrogen-containing Heterocycles

Recent Advances in Synthesizing and Utilizing Nitrogen-containing Heterocycles
Author: Hyun-Joon Ha
Publisher: Frontiers Media SA
Total Pages: 101
Release: 2024-05-31
Genre: Science
ISBN: 2832549187

Nitrogen-containing heterocycles, so-called aza-heterocycles, are widely found in natural products, pharmaceuticals, agrochemicals, and functional materials, and thus their synthesis has long been studied intensively. In addition, their preparation and utilization as synthons or intermediates from one to another are also developed to build higher and more complex aza-heterocycles. Some of them are also used as ligands for metal catalysts and organocatalysts. Despite many studies of the synthesis and utilization of nitrogen-containing heterocycles, a more efficient and general preparation is still required to diversify the structural backbones and improve their biological activities. Their usage as ligands and catalysts is also under expansion in various reactions.

Synthesis of Nitrogenous Heterocycles Via Group 3 Metal-catalyzed Hydroamination and Zinc (II) Mediated Metalloamination

Synthesis of Nitrogenous Heterocycles Via Group 3 Metal-catalyzed Hydroamination and Zinc (II) Mediated Metalloamination
Author: Adrian Robert Smith
Publisher:
Total Pages: 149
Release: 2015
Genre: Amination
ISBN:

Pyrrolidines and piperidines respresent a motif found in a wide array of bioactive compounds. Hydroamination, or the insertion of a carbon-nitrogen bond into a site of unsaturation, represents an atom economical method for accessing substituted pyrrolidines and piperidines. Synthesis of nitrogenous heterocycles through group 3 metal hydroamination and zinc(II) metalloamination has been achieved. The hydroamination of aminoalkenes has been thoroughly screened and has shown good tolerance for ethereal solvents, and solvent choice can result in improved rate and diastereoselectivity. The hydroamination of secondary amines with electron rich heteroatoms has also been realized utilizing a new group 3 metal trisamide developed in these labs. Additionally, zinc(II) metalloamination has been performed on N, N-dimethylhydrazinoalkenes and successfully resulted in the synchronous formation of a nitrogen-carbon bond to form a ring as well as carbon-zinc bond formation at the adjacent carbon. This carbon-zinc bond has been intercepted by different carbon electrophiles to synchronously form a nitrogen-carbon bond and carbon-carbon bond in situ. Ligand studies for these transformations suggest 1,1,1-trifluoroacetylenamines as well as acetoacetamides are promising motifs for future ligand scaffolds due to their ease of synthesis, low cost, and good reactivity with a range of N, N-dimethylhydrazinoalkene substrates.