Studies on the Development of Innovative Approaches for A Highly Stereocontrolled Construction of Structurally Diverse Fluoroalkene Skeletons

多様なフルオロアルケン骨格の高位体選択的構築のための革新的な合成手法の開発に関する研究

2015-03-25

2015-03-25

This thesis consists of five chapters. In Chapter 1 is referred the importance of fluoroalkene skeletons, together with general physical/chemical properties and availability of organofluorine compounds. In addition, precedent synthetic methods for the preparation of fluoroalkenes are presented. Chapter 2 describes an efficient chromium(II)-mediated reductive coupling reaction of various bromodifluoromethyl-containing molecules with aldehydes. It was revealed that the reaction proceeded very smoothly to afford the corresponding β-fluoroallylic alcohols in a highly stereoselective manner. It is particularly worth noting that (E)-β-fluoroallylic alcohols were exclusively given in the case of 3-(3-bromo-3,3-difluoropropanoyl)-2-oxazolidinone as a substrate, while (Z)-β-fluoroallylic alcohols were provided in the case of other substrates, such as 4-bromo-4,4-difluorobutylate, 3-bromo-3,3-difluoropropyl ether, and 1-bromo-1,1-difluoro-nonanes. Chapter 3 describes the unusual ring-opening reaction of gem-difluorocyclopropylstannanes, which were prepared via the radical hydrostannation of various gem-difluorocyclopropenes with n-Bu3SnH. Thus, on treating gem-difluorocyclopropylstannanes with MeLi, followed by quenching the reaction with various media, such as H2O, alcohols, carboxylic acids, and p-toluenesulfonamide, gave the corresponding β-fluoroallylic alcohols, ethers, esters, and amide in a highly Z-selective manner. Chapter 4 describes SN2’ substitution of β-fluoroallyl phosphates with organocopper reagents. It should be noted that various types of β-fluoroallyl phosphates reacted smoothly with various organoalkylcuprates, prepared from Grignard reagents, organolithium, organozinc reagents and CuCN, the corresponding terminal fluoroalkenes being obtained in a highly regioselective manner. Among thus obtained fluoroalkenes, fluorinated 1,7-dienes underwent a smooth ring-closing metathesis under the influence of Grubbs catalyst, providing the corresponding fluorinated cyclohexenes in high yields. In Chapter 5 is summarized the discussion in each chapter.

博士（工学）

京都工芸繊維大学

14303甲第732号

http://hdl.handle.net/10212/2252

en

ETD

Thesis or Dissertation

Thesis