Synthetic, Mechanistic, and Catalytic Studies of Nickel- and Palladium-Catalyzed Carboxylation with Carbon Dioxide

by Hee Won Suh

Institution: Yale University
Year: 2015
Keywords: Chemistry
Posted: 02/05/2017
Record ID: 2122913
Full text PDF: http://pqdtopen.proquest.com/#viewpdf?dispub=3663655


This dissertation describes the synthesis and characterization of a series of pincer ligand-supported group 10 transition metal hydride complexes and studies of their fundamental reactivity, with particular emphasis on their application in catalytic reactions that utilize carbon dioxide (CO2). Chapter 1 provides a short review of historically relevant transition metal-mediated complexes that react of CO2. Chapter 2 summarizes the synthesis and characterization of pincer ligand-supported group 10 metal hydrides with various pincer central donors, as well as their stoichiometric reactivity with CO2. Both experimental and computational studies show that the thermodynamic favorability of CO2 insertion into M-H bond increases with stronger trans-influence of the pincer central donor. Furthermore, decomposition of PSiP pincer metal hydrides to dimers with unusual bridging hypervalent silicon atoms is examined. PSiP pincer-supported palladium complexes have also been shown to catalyze carboxylation of allenes with CO 2, a singular example of this kind, and Chapter 3 discusses a detailed mechanistic study of this catalysis. PSiP palladium(II) hydride also mediates the hydroboration of carbon dioxide with a remarkably high turnover number, a significant improvement of literature precedent. Finally, Chapter 4 explores various stoichiometric and catalytic reactions with PSiP pincer-supported nickel cyclooctenyl complex that is proposed to be a synthetic equivalent of nickel hydride.