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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Imines in copper-catalyzed cross-coupling reactions

Black, Daniel. January 2006 (has links)
The purpose of this study was to develop new catalytic methods to mediate carbon-carbon bond forming reactions with imines under mild conditions and in a general manner. We found that copper catalysts were compatible in cross-coupling of a range of mild organometallic reagents, providing simple, efficient routes to alpha-substituted amides and amines. / Chapter 2 of this thesis describes a new copper-catalyzed multicomponent synthesis of alpha-substituted amides. This reaction was developed based upon previous work in this laboratory, which showed that palladium catalysts were competent in Stille-type cross-coupling of imines, acid chlorides, and organostannanes. While providing a mild method of generating the amide products, a more general procedure able to incorporate a wider range of organostannanes was sought. This chapter details the development of a copper-catalyzed protocol, which, as well as performing the cross-coupling under mild reaction conditions, proceeds with a diverse range of aryl-, heteroaryl-, and vinyl-substituted organostannanes and employs an inexpensive and readily available catalyst. Through this system, control over regioselectivity of addition to alpha,beta-unsaturated imines is also possible. / Chapter 3 demonstrates that, in addition to organostannanes, other substrates are viable in copper-catalyzed cross-coupling with imines and acid chlorides. Herein, the coupling of terminal alkynes with imines and acid chlorides is described, leading to an efficient synthesis of tertiary propargylamides directly from simple starting materials. This synthesis incorporates a wide variety of substituted imines, acid chlorides/chloroformates, and terminal alkynes, providing a rapid synthesis of these useful building blocks (reaction completion in only 15 minutes). In addition, the process is shown to work with aza-aromatic heterocycles, such as pyridine, where the alkynylation occurs exclusively at the 2-position. / Chapter 4 describes the utility of these rapid multicomponent reactions, where the products are directly converted into oxazole heterocycles. Copper-catalyzed- and zinc-catalyzed protocols are developed for the synthesis of secondary propargylamides from silyl-imines, acid chlorides, and terminal alkynes. The secondary propargylamide products are then, in a one pot sequence, transformed into trisubstituted oxazoles. / Chapter 5 describes the development of an atom-economical, non-toxic alternative to the organotin coupling described in Chapter 2. This involves the use of tri- and tetraorgano-indium reagents, which can transfer all of their organic groups in a copper-catalyzed coupling with imines and acid chlorides. This reaction shows good functional group compatibility and further expands the scope of alpha-substituted amides and N-protected amines that can be synthesized through mild copper catalysis. / Chapter 6 explores the enantioselective alkynylation of nitrogen-containing heterocycles. As described in Chapter 3, heterocycles such as pyridine can undergo copper-catalyzed 1,2-addition with terminal alkynes upon activation by chloroformates. As this process generates a stereocenter, it is possible to introduce enantio-control into the reactions by using a chiral copper catalyst. With ligands from the PINAP series, enantioselectivities of up to 84% can be induced in the coupling of nitrogen-containing heterocycles (e.g., quinoline), chloroformates, and terminal alkynes. This provides a mild and simple synthesis of chiral 2-alkynyl-1,2-dihydroquinolines directly from simple starting materials.
22

The sequential insertion of carbon monoxide and imines into nickel-carbon [sigma]-bonds and kinetic analysis of imine insertion into palladium-acyl [sigma]-bonds

Stafford, Carolyne. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Chemistry. Title from title page of PDF (viewed 2008/01/16). Includes bibliographical references.
23

Addition of Alpha-chloromethyl phenyl sulfone carbanion to imine bond : part II : Solvolysis of Beta-hydroxy-Alpha iodomethyl phenyl sulfoxides /

Chitchanun Panyachotipun, Vichai Reutrakul, January 1983 (has links) (PDF)
Thesis (M.Sc. (Organic Chemistry))--Mahidol University, 1983.
24

Brønsted acid promoted additions of diazoalkanes to imines the interplay of mechanism and stereochemical outcome as a tool to discover and develop a new syn-glycolate Mannich reaction /

Troyer, Timothy Lloyd. January 1900 (has links)
Thesis (Ph. D. in Chemistry)--Vanderbilt University, Dec. 2008. / Title from title screen. Includes bibliographical references.
25

A new system for catalytic asymmetric epoxidation

Rassias, Gerasimos A. January 1999 (has links)
This thesis concerns the catalytic asymmetric synthesis of epoxides. An introduction highlights the utility of chiral epoxides in asymmetric synthesis. The important methods that have been developed towards the construction of this influential functional group are also described.
26

Syntéza pokročilých intermediátov na báze para-bis (2-thienyl) fenylenu so zabudovaným adamantanovým skeletom. Vplyv intramolekulárnych vodíkových väzieb na fotoizomerizáciu. / Synthesis of advanced adamantane containing intermediates based on para-bis (2-thienyl) phenylene. Influence of intramolecular hydrogen bonds on photoisomerization

Veselý, Dominik January 2021 (has links)
This diploma thesis describes study and onward synthesis of advanced organic structures with potential application in the field of organic electronics and, in particular, molecular photoswitches. In the theoretical part of the thesis are closely described most commonly used conventional molecular photoswitches with special attention to the influence of the structural modifications on properties and applications of the given derivatives. Next passage is dedicated to study of donor-acceptor systems, as fundamental building blocks for synthesis of advanced derivatives. The possibilities of derivatization with a goal of improving the physicochemical properties of these compounds are also discussed. In the final chapter are proposed modern synthetic methods for preparation of novel materials for organic electronics. This section is connected with an experimental part, where are designed and consequently synthesised 4 novel imine derivatives with dodecyl and adamantyl-ethyl side chain.
27

Imines in copper-catalyzed cross-coupling reactions

Black, Daniel. January 2006 (has links)
No description available.
28

Part I: A study of N-acyliminium ion rearrangements and their application to the synthesis of pyrrolizidine alkaloids ; Part II: Preparation of [beta]-lactams via condensation of lithium ester enolates and imines /

Yang, Teng-Kuei January 1983 (has links)
No description available.
29

Part I, reaction of quinone imine monoketals with organolithium reagents. ; Part II, preparation of quinone imide monoketals by anodic oxidation of anilides. ; Part III, construction of the erythrina alkaloids skeleton /

Chou, Chun-Tzer January 1987 (has links)
No description available.
30

Aminoketene. Cycloaddition of Ketenes and Imines to Yield β- or δ- Lactams

Dad, Mohammad M. (Mohammad Mehdj) 12 1900 (has links)
The purpose of this investigation was to provide a systematic study of the cycloaddition pf (N-alkyl-N-phenylamino)- methoxy-and dichloroketenes to various imines and to investigate the stereochemistry of these cycloadditions.

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