Metal Triflate-Catalyzed Decarboxylation and sp3 C-H Bond Bromination of Carbonate Compounds.

Abstract

In chapter 1. The ether functional group is one of the most fundamental structures of chemistry and is used in various ways such as building blocks and protecting groups in organic chemistry. In most cases, alkyl halide is essential to generate ether functional group. We conducted research on a method of synthesizing ether functional groups using carbonate compounds. When metal triflate was added as a catalyst to carbonate compounds, decarboxylation was occurred and ether was synthesized. Among various metal triflates, Hafnium triflate was the best catalyst of this reaction. By expanding the scopes of carbonate compounds through this decarboxylation reaction, it was observed that the C-O bond of the carbonate group was broken and the better the carbocation was formed, the higher the yield was. This mild and effective decarboxylation reaction presents a novel way to synthesize various benzyl ethers.

In chapter 2. Since C-H activation of sp3 carbon is useful in total synthesis of natural products and pharmaceutical synthesis, various studies have been conducted in all areas of chemistry in recent decades. We have used the concept of microreversibility for C-H activation. Microreversibility refers to the process of generating a final product that is more thermodynamically stable than the starting material, although the reverse reaction is dominant in the reaction intermediate generation process. In our laboratory, there has been a case of successful sp3 carbon bromination reaction by adding NBS and metal triflate to 1-phenylethyl acetate. To expand the functional group from acetate to carbonate, reactions were screened using various catalyst conditions and bromination reagents.