Silyloxyarenes as C-O Electrophilic Coupling Partners Enabled by Nickel Catalysis

Silyloxyarene;C-O Bond Coupling;Nickel Catalysis;Chemistry;Science;Chemistry

Wiensch, EricWolfe, John P ;

University of Michigan

关键词: Silyloxyarene;    C-O Bond Coupling;    Nickel Catalysis;    Chemistry;    Science;    Chemistry;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/146110/ewiensch_1.pdf?sequence=1&isAllowed=n

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Silane protecting groups are traditionally only viewed as inert protecting groups to mask an alcohol functionality, allowing for orthogonal reactivity compared with other protecting groups and chemoselective protection or deprotection through silane attenuation. Therefore, due to the prevalence of silyl ethers in organic chemistry, they are attractive as C-O bond coupling partners that can be carried through syntheses for direct late-stage coupling without intermediate deprotection-activation strategies. However, silyloxyarenes have not been viewed as competent C-O coupling partners, and exploration of their C-O bond reactivity and general use as electrophilic coupling partners have not been previously developed as a general strategy. In this thesis, silyloxyarene C-O bond reactivity has been explored through development of new silylation and reduction reactions, allowing for direct comparison to other electrophilic coupling partners.Additional cross-coupling reactions have been developed, including amination, borylation, and Suzuki couplings to display the utility of silyloxyarenes as C-O electrophiles. Orthogonal couplings with aryl methyl ethers have been developed where chemoselective coupling of either electrophile can be obtained by catalyst-controlled selectivity. Sequential coupling routes with silyloxyarene C-O bonds are described, demonstrating where current silyloxyarene C-O bond coupling reactions can be applied. Additionally, these routes display examples of carrying a silyloxyarene C-O bond through numerous steps for late-stage coupling. Finally, preliminary future work includes utilizing other classes of silyl-protected C-O bonds, developing an unrealized electrophile into a general handle for diversification.