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Nickel-Catalyzed Cross-Electrophile Coupling: Methodology Development and Mechanistic Insights.
Nickel-Catalyzed Cross-Electrophile Coupling: Methodology Development and Mechanistic Insights.
- 자료유형
- 학위논문
- Control Number
- 0017163039
- International Standard Book Number
- 9798383228388
- Dewey Decimal Classification Number
- 540
- Main Entry-Personal Name
- Su, Zhi-Ming.
- Publication, Distribution, etc. (Imprint
- [S.l.] : The University of Wisconsin - Madison., 2024
- Publication, Distribution, etc. (Imprint
- Ann Arbor : ProQuest Dissertations & Theses, 2024
- Physical Description
- 397 p.
- General Note
- Source: Dissertations Abstracts International, Volume: 86-01, Section: B.
- General Note
- Advisor: Stahl, Shannon S.
- Dissertation Note
- Thesis (Ph.D.)--The University of Wisconsin - Madison, 2024.
- Summary, Etc.
- 요약Transition metal-catalyzed coupling reactions are the predominant methods for carbon-carbon bond formation in synthetic chemistry. Nickel-catalyzed cross-electrophile coupling (XEC) reactions have emerged as a promising alternative to conventional cross-coupling strategies that employ organometallic nucleophiles as coupling partners. Ni-catalyzed XEC reactions feature the direct coupling of two electrophiles enabled by Ni-catalysis that requires a stoichiometric source of electrons from chemical reductants or electroreduction. This strategy offers several benefits, such as the utilization of stable and widely available carbon electrophiles, operational simplicity, and great functional group tolerance. Consequently, notable advancements in Ni-catalyzed XEC reactions have been achieved over the past decades. This thesis describes the efforts towards the development, mechanistic understanding, and application of Ni-catalyzed XEC methods.Chapter 1 provides a high-level overview of Ni-catalyzed XEC reactions, including their first disclosures, development, and current state of the art. Reaction mechanisms and strategies for achieving cross-selectivity in Ni-catalyzed XEC reactions are also discussed.Chapter 2 discloses an electrochemical method that converts lignin-derived aromatic compounds into a collective of substituted biphenyl-4,4'-dicarboxylic acid (BPDA) derivatives via Ni- and Ni/Pd-catalyzed XEC. The synergy between chemical and electrochemical conditions is highlighted, showing that high-throughput experimentation with chemical reductants enables rapid catalyst discovery while electrochemistry improves reaction yields and/or facilitates implementation on larger scale. The resultant BPDA derivatives exhibit improved poly(vinyl chloride) (PVC) plasticizer performance and reduced toxicity relative to a commercial plasticizer.Chapter 3 describes the application of open-circuit potential measurements to determine the redox potentials of metal reductants in organic solutions. Different organic solvents and reaction additives are shown to significantly impact the thermodynamic potentials of metal reductants. Fundamental insights can be gained through the study of the relationship between reductant redox potentials and critical redox processes in XEC reactions. Finally, Ni-catalyzed XEC of N-alkyl-2,4,6-triphenylpyridinium reagents (Katritzky salts) with aryl halides is used to demonstrate how some of the limitations related to using metal reductants can be overcome by highly tunable electrochemical reduction.Chapter 4 details the development of a general strategy for the XEC of heteroaryl chlorides with aryl bromides via Ni-catalysis. Two sets of reaction conditions (A and B) have been identified to enable the coupling of a variety of heteroaryl chlorides and aryl bromides containing an array of functional groups and steric environments. Condition A is particularly effective for the coupling of 2-chloropyridines with aryl bromides. Mechanistic investigations into condition A suggest a Ni-catalyzed in situ aryl-zinc formation, followed by a Ni-catalyzed cross-coupling between aryl-zinc and 2-chloropyridines. Condition B is usually preferred for the XEC of diazaheteroaryl chlorides with aryl bromides. In this case, preliminary studies reveal the synergistic effects of NaI and FeBr2 to match the relative reactivity of the two coupling partners and achieve high cross-selectivity.Collectively, the studies presented herein are envisioned to enable the utilization of a broader scope of electrophiles in Ni-catalyzed XEC reactions and facilitate a better mechanistic understanding.
- Subject Added Entry-Topical Term
- Chemistry.
- Subject Added Entry-Topical Term
- Physical chemistry.
- Subject Added Entry-Topical Term
- Analytical chemistry.
- Subject Added Entry-Topical Term
- Organic chemistry.
- Index Term-Uncontrolled
- Catalysis
- Index Term-Uncontrolled
- Cross-electrophile coupling
- Index Term-Uncontrolled
- Electrochemistry
- Index Term-Uncontrolled
- Methodology
- Index Term-Uncontrolled
- Nickel
- Index Term-Uncontrolled
- Organic synthesis
- Added Entry-Corporate Name
- The University of Wisconsin - Madison Chemistry
- Host Item Entry
- Dissertations Abstracts International. 86-01B.
- Electronic Location and Access
- 로그인을 한후 보실 수 있는 자료입니다.
- Control Number
- joongbu:656998