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학위논문 (석사)-- 서울대학교 대학원 : 화학생물공학부, 2017. 2. 이윤식.ABSTRACT Preparation of Pd-NHC Catalyst Immobilized on γ-Alumina for Suzuki-Miyaura Cross-Coupling Reaction Min-Ki Kang School of Chemical and Biological Engineering The Graduate School Seoul National University γ-Alumina (γ-aluminium oxide) supported palladium(II)-N-heterocyclic carbene (Pd-NHC) complex is one of the effective Suzuki-Miyaura cross-coupling catalysts in water dominant environment. NHCs are stable ligands in aqueous conditions, and they have been used for spectator ligands of Suzuki-Miyaura cross-coupling catalyst. γ-Alumina is one of the suitable solid supports due to its hydrophilicity and large surface area but has not been fully studied for Suzuki-Miyaura reaction. In this research, two kinds of 1-substituted imidazoles were synthesized as precursors of NHCs, and Pd-NHC complexes were prepared by using Pd(OAc)2 and these precursors. Finally, the catalysts were prepared by immobilizing the Pd-NHC complexes on γ-alumina. The catalysts were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron mictrscope (SEM), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The catalytic activity was investigated under various solvents and basic conditions via conventional heating or microwave heating methods. As a result, up to 99% yields were obtained from the reactions of aryl bromides with phenylboronic acid at 50℃ for 2 h.I. Introduction 1 I. 1. Suzuki-Miyaura Reaction in Water 2 I. 2. Pd-NHC Complex in Suzuki-Miyaura Reaction 3 I. 3. Heterogenous Pd-NHC Suzuki-Miyaura Catalyst 5 I. 4. γ-Alumina as a Catalyst Support 6 I. 5. Microwave-Assisted Suzuki-Miyaura Reaction 7 I. 6. Research Objectives 8 II. Experimental Section 9 II. 1. General 10 II. 1. 1. Materials 10 II. 1. 2. Instruments 10 II. 2. Preparation of γ-Alumina Supported Pd-NHC 12 II. 2. 1. Synthesis of 1-Substituted Imidazoles 12 II. 2. 2. Preparation of 3-(Iodopropyl)triethoxysilane 14 II. 2. 3. Preparation of NHC precursors 15 II. 2. 4. Immobilization of Pd-NHC Complex on γ-Alumina 18 II. 3. Suzuki-Miyaura Reaction Catalyzed by γ-Alumina Supported Pd-NHC 21 II. 3. 1. General Experimental Procedure for Suzuki-Miyaura Reaction 21 II. 3. 2. Optimization of Suzuki-Miyaura Reaction in Various Solvents and Bases 22 II. 3. 3. Determination of Reaction Kinetics 23 II. 3. 4. Reaction Profiles at Various Temperature by using Microwave as Heating Method 24 II. 3. 5. Reusability of γ-Alumina Supported Pd-NHC 25 III. Results and Discussion 26 III. 1. Preparation and Characterization of γ-Alumina Supported Pd-NHC 27 III. 1. 1. Preparation of γ-Alumina Supported Pd-NHC 27 III. 1. 2. Characterization of γ-Alumina Supported Pd-NHC 30 III. 2. Suzuki-Miyaura Reaction Catalyzed by γ-Alumina Supported Pd-NHC 36 III. 2. 1. Effects of Solvents and Bases in Suzuki-Miyaura Reaction 36 III. 2. 2. Reaction Profiles of Suzuki-Miyaura Reaction 46 III. 2. 3. Suzuki-Miyaura Reaction of Various Aryl Halides with Phenylboronic acid 51 III. 2. 4. Reusability of γ-Alumina Supported Pd-NHC for Suzuki-Miyaura Reaction 54 IV. Conclusion 59 References 61 국문 초록 67 Appendix 68Maste