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    DateTitleAuthors
    有機金屬金、銀;炔類分子環化加成;碳烷氧基化 Chapter I
    We report the Ag(I)-catalyzed tandem 6-exo-dig-azacyclization/[3+2] cycloaddition cascades on 1-tosylhydrazon-4-oxy-5-ynes to form complicated azacyclic products efficiently. Control experiments exclude the intermediacy of isoquinolinium species because of its poor activity in the cycloaddition with enol ether. We hypothesize that the [3+2] dipolar cycloadditions likely occur on non-aromatic zwitterionic intermediates.

    Chapter II
    We report herein the gold-catalyzed cyclization/oxidative [3+2] cycloadditions of 1,5-enynes with nitrosobenzenes. Notably, nitrosobenzenes not only provide two-atom building units, but also lead to the alkyne oxidation. Such a reaction pattern is unprecedented in metal-catalyzed cycloadditions of 1,n-enynes.
    V


    Chapter III
    We have developed a formal [2+2+2] cycloaddition of 1,5-enyne with aldehydes or nitrosobenzenes to give cyclobutene derivatives. This reaction involves the cyclopropyl gold carbene intermediate, which is trapped by aldehydes or nitrosobenzenes.

    Chapter IV
    In this work, we demonstrate the effects of the counter anions (X) of P(t-Bu)2(o-biphenyl)X and water, to control the regioselective formation of 1- or 3-substituted 2-methoxy-1-H-indenes from the same

    VI
    2-alkynylbenzyl ethers
    ; these two indenyl ethers can be oxidative cleaved by O3 to give two distinct highly oxygenated products, thus highlighting the synthetic utility.; zh
    金催化反應;銅催化反應;氧化環化反應;氧化二聚體環化反應;金屬碳烯化合物 ABSTRACT
    This dissertation describes development of new synthetic organic transformations by using gold and copper salts. The use of these soft alkynophilic metals enables mild, diastereoselective and efficient transformations of a variety of readily available substrates to wide range of synthetically useful and biologically important N, O containing heterocyclic and carbocyclic products. For better understanding the thesis is divided into four chapters.

    The first chapter deals with the Gold-catalyzed oxidative cyclizations of cis-3-En-1-ynes to form cyclopentenone derivatives. The title reaction for synthesizing cyclopentenone derivatives utilizes a gold complex and 8-methylquinoline oxide as the catalyst system. The value of such reactions is reflected by their applicability to a broad range of benzene- and nonbenzene-derived substrates, thus giving various indanone and cyclopentenone derivatives, respectively. Such products are not attainable using diazocarbonyl reagents, as the gold carbenoids tend to react with C-H bonds.

    The second chapter deals with the gold-catalyzed oxidative cyclizations of 1,4-enynes were used to study the γ-effect on the Wagner–Meerwein rearrangement. Both experimental and theoretical work disclose that a gold substituent in the γ-position can direct a stereospecific 1,2 shift of the anti-β-substituent regardless of its intrinsic properties.

    The third chapter describes gold-catalyzed reactions of 3,5- and 3,6-dienynes with 8-alkyl- quinoline oxides results in an oxidative cycloaddition with high stereospecificity, this process involves a catalytic activation of a quinoline framework. The reaction mechanism involves the intermediacy of α-carbonyl pyridinium ylides (I) in a concerted [3+2]-cycloaddition with a tethered alkene.

    The fourth chapter presents the work aim at one-step construction of complex and important molecular frameworks via Cu-catalyzed oxidations of cheap tertiary amines. Cu-catalyzed aerobic oxidations of N-hydroxyaminopropenes to form C2-symmetric N- and O-functionalized cyclohexanes.
    ; en
    金金屬催化反應;氮氧雜環;波瓦羅夫反應 Abstract
    This dissertation describes development of new synthetic organic transformations by using transition metal catalysis. The use of gold and rhodium metals enables mild, diastereoselective and efficient transformations of variety of readily available substrates to wide range of synthetically useful nitrogen and oxygen containing heterocyclic products. For convenience and better understanding, this thesis is divided into four chapters.
    The first chapter describes the two new formal cycloaddition reactions between nitrosobenzenes and alkenylgold carbenoids. We obtained quinoline oxides in good to better yields from the gold-catalyzed [3+3]-cycloadditions between nitrosobenzenes and alkenyldiazo esters. For propargyl esters, its resulting gold carbenes react with nitrosobenzene to give alkenylimine, followed by a [4+2]-cycloaddition with nitrosobenzene to form 1, 2-oxazines.

    The second chapter deals with the development of an oxa-Povarov reaction/carbene generation sequence for alkenyldiazocarbonyl compounds. A triflic acid catalyzed reaction of vinyl diazoacetate with diphenoxymethylbenzene to give diazo-containing cycloadducts stereoselectively with fruitful range of substrate scope. The dihydrobenzopyran core moiety found in many natural product and bioactive molecules.

    The third chapter explains, the gold-catalyzed reactions between vinyldiazo carbonyl species and acetals to obtain selectively E-configured alkyl 3,5-dimethoxy-5-pent-2- enoates in good yields. According to our experimental data, this reaction sequence involves an initial Prins-type reaction, followed by gold-carbene generation. The success of this Prins-type reaction indicates a stabilization effect of the diazo functionality on the adjacent carbocation.

    The fourth chapter provides gold-catalyzed oxa-Povarov reactions involving readily available diaryloxymethylarenes and aryl-substituted alkenes to give dihydrobenzopyrans
    ; their [4+2]-cycloadditions are efficiently catalyzed by gold catalysis with high diastereoselectivity. The cycloadditions were applicable to broad range of substrate under ambient conditions. Product analysis reveals that the reaction likely proceeds via a stepwise ionic mechanism because both E- and Z-configured β-methylstyrene gave the same cycloadducts in the same proportions.; en
    金金屬催化反應;?;環氧化合物;胺炔類化合物 Abstract
    This dissertation describes development of new synthetic organic transformations by using gold salts. The use of this soft alkynophilic metal enables mild, diastereoselective and efficient transformations of a variety of readily available substrates to wide range of synthetically useful highly functionalized products. For better understanding the thesis is divided into four chapters.
    The first chapter deals with the gold-catalyzed 1,2-oxoarylations of nitriles with pyridine-derived oxides. This is the first success in the gold-catalyzed oxoarylations of nitriles using gold carbenes as initiators leading to benzo[d]azepine frameworks. Such azacyclic core is one of the most commonly encountering skeletons in nature and the core scaffold has a wide spread application in structural, biological importance. These oxoarylations were also achieved satisfactorily in intermolecular three-component oxidations, including diverse alkenyldiazo esters, nitriles, and pyridine-based oxides.



    The second chapter deals with the gold-catalyzed regiocontrolled [2+2+2]-cycloadditions of ynamides with two discrete nitriles to construct 4-aminopyrimidine cores pharmaceutically important structural motifs. The utility of this new cycloaddition is manifested by the excellent regioselectivity with applicable ynamides and nitriles over a wide scope.



    The third chapter describes the retention of stereochemistry in gold-catalyzed formal [4+3]-cycloaddition of epoxides with arenyanamides. The utility of this new [4+3]-Cycloaddition reaction is manifested by a wide scope of arenynamides and epoxides. An SN2-type front-side attack of phenyl at the oxiranyl ring is expected to cause the retention of stereochemistry.



    The fourth chapter presents gold-catalyzed 1,2-difunctionalizations of aminoalkynes using Only N- and O-containing oxidants. In the presence of IPrAuNTf2, nitrosobenzenes implements a novel oxoimination of aminoalkynes to form 2-oxoiminylamides that are then subjected to NaBH4 reduction in situ to deliver 2-aminoalcohols.
    ; en
    鈷金屬錯合物催化;N-三甲基乙?基苯胺;碳-氫鍵活化;銠金屬錯合物催化;酮? 芳基 - 芳基鍵的形成,是現代有機合成領域中最重要的工具之一。這些鍵結結構經常在天然物中發現,如生物鹼,以及在醫藥和農業化學品方面。特別是碳-氫鍵活化反應的方法來合成具有生物活性化合物,存在著高度位置選擇性與立體選擇性。在這方面,本文的描述著眼於芳基硼酸與苯氧乙?、2-(2-甲?基苯氧基)乙?之加成反應,成功地以鈷金屬錯合物催化此類型反應。經由 碘苯、N-三甲基乙?基苯胺、苯硼酸與酮?、芳族羧酸的碳-氫鍵官能化反應,得到各種官能化之聯芳基。關於酮?與苯硼酸在多步碳-氫鍵活化之一鍋化反應,得到具有生物活性的菲啶衍生物。為了清楚地說明,將論文分為四個章節。第一章描述關於苯氧乙?與2 -(2-甲?基苯氧基)乙?和有機硼酸的鈷催化加成反應。接下來的三個章節介紹有關碳-氫鍵活化反應之?苯胺類、酮?與芳香族氨基酸、有機硼酸和碘苯的銠金屬錯合物催化環化反應。

     第1章介紹鈷金屬錯合物催化芳基硼酸與苯氧乙?,合成具有生物活性之高產率芳基酮化合物。

     第2章介紹有關第一個以銠金屬錯合物催化N-三甲基乙?基苯胺與碘苯之鄰位芳基化反應。

     第3章說明銠金屬錯合物催化一鍋化碳-氫鍵官能化反應,酮?與芳基硼酸之偶聯反應以合成菲啶衍生物。

     第4章介紹銠金屬錯合物催化芳香酸與芳基硼酸之碳-氫鍵偶合反應。
    ; en
    銠金屬;碳氫鍵活化;異??;醛;炔;胺;苯亞胺 en
    染料敏化太陽能電池 zh
    一氧化氮;雙亞硝基鐵錯合物;氫化酵素 en
    金催化;銀催化;環化反應;加成反應 zh
    有機染料晶體;聚合反應;有機配位鋅磷酸鹽;光致發光 zh; en
    有機電激發光二極體;雙極性;主體材料;客體摻雜物;電子傳輸層材料;染料敏化太陽能電池;順式二苯乙烯/芴 1.Spirally Configured cis-Stilbene/Fluorene Hybrids as Ambiplor Templates for Organic Light Emitting Diode Applications

    Organic light emitting diodes (OLEDs) have been intensively investigated in the recent years for their potential applications in next generation full-color at panel displays and solid state lighting. However, the recombination efficiency of holes and electrons with unbalanced-charge carriers is one of the key factors for making bad device efficiencies. Therefore, we developed a new class of cis-stilbene/fluorene spiro hybrid systems with hole-transporting, electron-transporting and ambipolar organic fluorescent materials for optoelectronic applications. These types of materials exhibited a stable amorphous glassy state (Tg:120-167 oC) and stable decomposition temperatures (Td: >400 oC). One of the fluorescent materials, N-STIF-P(O)Ph2, had ambipolar charge transport feature with balanced hole and electron mobilities (μh: 6.510-6 cm2/Vs
    ; μe: 5.110-6 cm2/Vs @7.3 105 V/cm). This feature allowed us to utilize N-STIF-P(O)Ph2 successfully in a single-layer device (i.e., ITO/PEDT:PSS/ N-STIF-P(O)Ph2/LiF/Al) with excellent performance. The single layer device emitted bluish green light and showed a turn-on voltage of 2.5 V, a
    maximum brightness of 73,359 cd/m2 at 5,611 mA/cm2 (8.5 V), operational current efficiency of 3.29 cd/A, power efficiency of 2.84 lm/W and EQE of 1.28% at 20 mA/cm2 with CIE color coordinates of (0.21, 0.47). Next, we demonstrated red-emitting PhOLED using the P(O)Ph2-STIF-P(O)Ph2 as the electron-transporting type host material and [Os(bpftz)2(PPhMe2)2 , OS1] as red dopant (i.e., ITO/PEDT:PSS/NPB /TCTA/ P(O)Ph2-STIF-P(O)Ph2: 10 wt% OS1/3TPYMB/LiF/Al). This device with highly efficient performance was successfully achieved, with maximum current efficiency of 22.2 cd/A, power efficiency of 23.3 lm/W, EQE of 16%, and a maximum brightness of 29,602 cd/m2 at 1,759 mA/cm2 (10 V) with CIE color coordinates of (0.63, 0.36). And then, we fabricated fluorescent white OLEDs based on 0.4 wt% rubrene-doped Cbz-STIF-P(O)Ph2 (i.e., ITO/PEDT:PSS/NPB /TCTA/ Cbz-STIF-P(O)Ph2: 0.4 wt% Rubrene/TPBI/LiF/Al). This device showed a turn-on voltage of 3.1 V, a maximum brightness of 87,800 cd/m2 at 1,719 mA/cm2 (14.5 V), operational current efficiency of 11.3 cd/A, power efficiency of 4.23 lm/W and EQE of 3.62% at 1,000 cd/m2 with CIE color coordinates of (0.45, 0.48). Compared with the CIE color coordinates of the ideal white light (CIE: 0.33, 0.33), there were 36-45% gaps between our device and ideal WOLED. However, our device was very close to the white light by the naked eye. And this device had already achieved the best performance and the most stable state. And Next, we tried to fabricate blue OLED based on thermally activated delayed fluorescence (TADF) device configuration developed by Prof. Adachi. For this blue OLED, we used the DPEPO as host material and Cbz-STIF-cbz as TADF material (i.e., ITO/PEDOT:PSS/NPB/TCTA/CzSi/DPEPO: 10 wt% Cbz-STIF-cbz/DPPS/BmPyPB/LiF/Al). Although there was no TADF observed in Cbz-STIF-cbz, this was still good device performance for blue OLED. And this device showed a turn-on voltage of 4.1 V, a
    maximum brightness of 2,778 cd/m2 at 538 mA/cm2 (13.5 V), maximum current efficiency of 2.5 cd/A, power efficiency of 2.19 lm/W and EQE of 3.81% with CIE color coordinates of (0.15, 0.07). Finally, we used a highly efficient and ambipolar-type material, N-STIF-CN, as electron transporting material for green, yellow and red PHOLEDs. Compared with those devices which used common electron transporting materials (i.e., Alq3, TPBI, BmPyPB, etc.), our devices had further improved the device efficiencies and lifetime. For example, we demonstrated green PhOLED using the industry’s device configuration (i.e., ITO/HAT-CN /HT-01: 3 wt% F4-TCNQ /NPB/ TPBI: 5 wt% Ir(ppy)3/ ETL/ LiF/Al), without any hole blocking layer, N-STIF-CN could further supplant ET-01 which was often used in the industry as superior ET material with improved power efficiency by 29%, current efficiency by 29%, and EQE by 28% at 1,000 cd/m2. And for device lifetime tests, the half-life of N-STIF-CN was 210 hours and it was very close to the half-life of ET-01 which was 270 hours under the initial brightness of 1,000 cd/m2. Therefore, N-STIF-CN was very promising material based electron transporting layer for PHOLEDs.

    2.Spirally Configured cis-Stilbene/Fluorene Hybrids as Ambiplor Templates for Dye-Sensitized Solar Cell Applications

    A new class of cis-stilbene/fluorene spiro hybrid systems with di-p-tolylamine donor and combined benzothiadiazole (BTD) and thiophene (T) acceptor units at C-3 and C-7, respectively, were synthesized as two novel D-π-π-A-A-featured dye N-STIF-T-BTD-CA and D-π-A-π-A-featured dye N-STIF-BTD-T-CA for dye-sensitized solar cell applications. These two dyes whose maximum absorption wavelength were observed at 470 nm and 523 nm, respectively, and the molar absorption coefficient were observed at 20,801 M-1 cm-1 and 21,690 M-1 cm-1, respectively. The best device performance was D-π-A-π-A-featured dye N-STIF-BTD-T-CA, and it showed a conversion efficiency (η) of up to 4.26% (Voc = 643 mV, JSC = 8.81 mA/cm2, FF = 0.74) under AM 1.5 G conditions. And the best IPCE values achieved 49.3% within the 400–550 nm absorption range.
    ; zh
    有機發光二極體;深藍光;延遲螢光;高效率;壽命 因申請專利緣故,資料延後公開; zh
    核殼奈米晶體;超級晶體;表面電漿共振;集體共振;氫氣感測;鈀;金 Core?shell nanoparticles are highly functional materials with modified properties by changing either the constituting materials or the core to shell ratio. Various core?shell nanostructures have been synthesized such as Au?Cu2O, Au?Ag, Au?Cu, Pt?Pd, and Au?Pd core?shell nanoparticles. Among them, Au?Pd core?shell nanostructures have efficient catalytic properties for a variety of reactions and plasmonic gas sensing upon exposure to H2 as reversible H2 uptake from the Pd shell occurs. Furthermore, synthesis of well-defined Au?Pd core?shell nanocrystals with systematic shape evolution is still challenging by virtue of long reaction time.
    In Chapter 1, we have developed a facile aqueous solution method to synthesize Au–Pd core–shell nanocrystals with systematic shape evolution from cubic to octahedral structures in just 0.5–2 h at 50 oC. Octahedral gold nanocrystals were used as cores. Since an important purpose of this work is to systematically examine the plasmonic properties of these particles as a function of particle size, shape, and shell thickness, octahedral Au nanocrystal cores with sizes of 35, 45, 74, and 92 nm have been employed as the templating cores. Au–Pd core–shell cubes, truncated cubes, cuboctahedra, truncated octahedra, and octahedra with precisely tuned particle morphology and shell thickness have been achieved, allowing a thorough and detailed analysis of the plasmonic band appearance and shifts of these core–shell nanocrystals for the first time. Nanoparticles with uniformly thin shell thicknesses, particularly the core–shell octahedra, exhibit the most pronounced plasmonic band derived from the gold cores.
    In Chapter 2, we employed Au–Pd core–shell THH particles, octahedra, and nanocubes as hydrogen sensing materials. The nanocrystals were dispersed in an aqueous solution and hydrogen gas was introduced into a 10-mL flask through a syringe-attached balloon. Presence of dissolved hydrogen was detected. All of these nanocrystals were found to be excellent plasmonic hydrogen sensors producing very large spectral red-shifts after hydrogen absorption. THH nanocrystals exposing high-index facets displayed the largest spectral shifts. All these particles are highly selective to hydrogen. The spectral shifts are almost fully reversible with successive hydrogen absorption and desorption cycles. For smaller core–shell octahedra, the spectral changes can be visually observed. Larger particles with thicker Pd shells give the largest spectral red-shift. With all these advantages, these Au–Pd core–shell nanocrystals should find broad applications in which simple detection of hydrogen presence is desirable.
    In Chapter 3, we utilized gold, gold-palladium, gold-silver, and lead sulfide nanocrystals with cubic and octahedral structures as building blocks to fabricate supercrystals by solvent evaporation and surfactant diffusional methods. The supercrystals prepared were characterized by SEM, TEM, and XRD techniques. The microstructures were studied by small-angle X-ray scattering (SAXS) technique. The growth process was investigated. Shapes and sizes of various supercrystals were also controlled. These supercrystals are considered novel superstructures and may show interesting optical and electrical properties which may be used for the fabrication of metamaterials and photonic devices.

    In these works, we have developed a facile aqueous solution method to synthesize Au–Pd core–shell nanocrystals with systematic shape evolution from cubic to octahedral structures, allowing a thorough and detailed analysis of the plasmonic band appearance and shifts of these core–shell nanocrystals. We also employed polyhedral Au–Pd core–shell nanocrystals as hydrogen sensing materials. All these particles are highly responsive and reusable hydrogen sensors in aqueous solution. Furthermore, we utilized polyhedral Au–Pd core–shell nanocrystals as building blocks to fabricate 3D supercrystals, which are considered novel superstructures and may have opportunities for the fabrication of metamaterials and photonic devices.
    ; en
    有機催化反應;不對稱加成反應;有機催化劑;樟腦磺酸 This thesis deals with the application of camphor-derived organocatalyst in asymmetric addition reaction. The fisrt part discusses the asymmetric aldol reaction of 2,2-dimethyl-1,3-dioxan-5-one with aldehydes in the presence of 10 mol% organocatalyst 42 and 20 mol% p-nitrobenzoic acid to give aldol products in good yields with high enatio- and diastereoselectivities. (up to 99% ee, 4:96 dr)
    The second part deals with the development of camphorsulfonamdie-derived (2S,4R)-4-hydroxy-L-prolinamide 54b as organocatalyst. Catalyst 54b is able to catalyze asymmetric Michael addition of 2,2-dimethyl-1,3-dioxan-5-one to nitro alkenes. The asymmetric reaction could give γ-nitro-dihydroxyacetones in good yields with high enatio- and diastereoselectivities (up to 94% ee, 91:9 dr) in the presence of 10 mol% organocatalyst 54b, 5 mol% 2,4-dinitrophenol and 5 equiv. of water in toluene.
    The third part discusses pyrrolidine-camphorsulfonamide based catalyst 30 in the asymmetric catalytic Michael addition reaction of nitroalkanes to alpha,beta-unsaturated aldehydes without the addition of acid additive to produce desired products with up to 99% ee and good yields. The main advantage of this catalyst is high efficiency and enantioselectivity with low catalytic loading (1-2 mol%). These remarkable advantages make this approach very suitable for gram-scale synthetic use.
    ; zh
    生物交錯標示法 因申請專利緣故,資料延後公開; en
    鈷;不對稱催化;[3+2]環化;?胺;具立體選擇性的 In this thesis, we successfully develop cobalt-catalyzed [3+2] annulation reactions of imine with unsaturated bonds and synthesize aminoindane-and indenes derivatives with efficiency. By these methodologies, we can construct aminoindane or indene skeletons in one step and it is also powerful synthetic methods for the synthesis of relative aminoindane or indene natural product and drugs.
    In chapter 2, we develop cobalt-catalyzed [3+2] annulation of 2-iminoarylboronic acids with conjugate alkenes to synthesize aminoindane carboxylate derivatives with high chemo-and diastereoselectivity.
    In chapter 3, we extend the result of chapter 2 and synthesize aminoindene derivatives by cobalt-catalyzed [3+2] annulation of 2-iminoarylboronic acids with alkynes. Furthermore, we combine PHOX chiral ligands which are prepared from commercial available amino acids in the cobalt catalysis reaction and generate a series of chiral aminoindenes with high regio-and enantioselectivity.
    In the final chapter, based on our cobalt catalysis system of aryl halides with other substrates experience before, we develop cobalt-catalyzed asymmetric [3+2] annulation of 2-iminoarylbromides with alkynes to construct chiral aminoindenes. In this reaction, we can prepare multi-substituted chiral aminoindenes with good to excellent regio-and enantioselectivity. Besides, we can learn more about the relative position of chiral cobalt complex and substrates in the reaction environment via absolute configuration determination.
    ; zh; en
    金金屬;銀金屬;催化;環加成反應 zh
    路易斯鹼催化;丙二烯酯 en
    電激發光二極體 en
    主動式回饋磁共振成像;磁共振分子影像;腫瘤早期偵測;腦瘤;胰臟癌;超順磁氧化鐵奈米粒子 en
    金(111);併環?吩;成長模式;光電子光譜;有機場效電晶體 Recent years have seen an increasing number of studies on the utilization of fused thiophene-based materials for organic filed effect transistor (OFET) applications due to their strong intermolecular S-S interaction, large ionization potential energy, and better ambient stability. In OFETs, the interface between the electrodes and the organic semiconductor plays a critical role in affecting the device performance. In our work, the 2-phenylbenzo [d,d’]thieno-[3,2-b; 4,5-b’] dithiophene (P-BTDT) and its derivative, monofluorine-substituted 2–phenylbenzo [d,d_]thieno [3,2-b; 4,5-b_]–dithiophene (m-FP-BTDT), were grown on the Au (111) and modified Au (111) substrate as the organic semiconductor thin films, respectively. The growth mechanisms, the molecular orientations and the electronic structure of the thin films were analyzed via XPS, NEXAFS and UPS. In addition, the above results were combined with the XRD and AFM data to reach a thorough understanding of the performances of various OFETs. The thermal desorption data show that the chemisorbed P-BTDT layer remains thermally stable up to 750 K on Au(111). However, P-BTDT desorption on Au-BT substrate is found to derive exclusively from physisorption state, and chemisorption desorption is entirely suppressed. Based on the change of XPS intensity with the amount of P-BTDT deposited, it is concluded that the growth of P-BTDT film on Au(111) follows the Stranski-Krastanov mechansim, i.e., a completion of one monolayer (2D growth) followed by a 3D crystallite growth. In comparison, for the growth of P-BTDT on Au(111)-benzenethiolate, a pseudo 2D-like growth is observed. From the results of UPS, the change of work function and valence band spectrum with the film-thickness is in accord with this growth behavior. The results obtained by XPS are also in agreement with UPS observations. The molecules of the multilayer grown on Au(111)-BT have their aromatic rings inclined toward the surface by an average 66°, as determined by NEXAFS data. For the thick film grown on Au(111), out-of-plane x-ray diffraction reveals the presence of several crystallite alignment schemes. In contrast, the XRD data of the thicker layer grown on Au(111)-BT show (002) diffraction peaks only, indicating that the crystal orientation of the thin film is (002) preferred. Therefore, we can change the crystal structure and control the growth behavior of the thin film through different modification of substrates, leading to an improved performance of the OFETs. The results show that P-BTDT thin film that is grown on BT-Au can yield a better OFET mobility up to 3.0 × 10-2 cm2/Vs with thickness of 120 nm.
    In order to shift energy level of LUMO toward lower value, we also prepared m-FP-BTDT organic semiconducting thin films and investigated their properties. XPS intensity analysis shows that on Au(111), m-FP-BTDT film grows according to Stranski–Krastanov (SK) mode. It is interesting to note an abrupt increase of Au 4f signal at around one ML of m-FP-BTDT, which is explained by the production of excess Au adatoms, accompanied by the lifting of the herringbone reconstruction of Au(111). In comparison, the initial growth of m-FP-BTDT on Au-BT proceeds via a pseudo layer-by-layer growth mechanism. NEXAFS data show that m-FP-BTDT molecules on Au-BT adopt a more erected configuration, the angle between the molecule and substrate is 62.5°, resulting in a better cofacial π-stacking. The XRD pattern reveals that the crystal growth orientation of m-FP-BTD thin film is along c axis. Work function for the thick m-FP-BTDT film on Au-BT is determined with UPS as 4.62 eV and the hole injection barrier as 0.94 eV. According to above results the thin film of m-FP-BTDT grown on Au(111)-BT is expected to produce better carrier transport phenomenon.
    ; zh
    天然物全合成;Pterosin A. C. D.;不對稱合成;Entecavir This thesis consists of two part, the first part deals with the total synthesis of (±)-pterosin A, (R)-pterosin A, (S)-pterosin D and (2S,3S)-pterosin C. The synthesis of (±)-pterosin A started from the reaction of 2-bromo-1,3-dimethylbenzene 1 with -chloropropionyl chloride by using Friedel-Crafts acylation that followed by Nazarov cyclization to afford indanone 29. Indanone 29 is converted to -keto ester 50 by ethoxycarbonylation and methylation. The use of Suzuki coupling reaction is a key step in the synthesis to construct the C6-side chian and then after some functional group transformation -keto ester 50 is converted to (±)-pterosin A. In this synthesis, (±)-pterosin A was accomplished in 9 steps and 10% overall yield. In the synthesis of (R)-pterosin A, PLE (porcine liver esterase) is used to proceed desymmetrization of diester 90 to afford known chiral compound 91. compound 91 is converted to vinyl iodide 95 followed by Stille coupling to afford diene 97. Diene 97 is converted to diene-ynone which could be directly subjected to intramolecular Diels-Alder reaction/aromatization to give (R)-pterosin A. By using the same strategy in the synthesis of (R)-pterosin A, (2S,3S)-pterosin C is synthesized form the known compound aldehyde 109 of Evans’ aldol reaction to give diene 111 with suitable skeleton and chiral center at C2 and C3 of pterosin C. Then, diene 111 was transformed into diene-ynone 113 followed by intramolecular Diels-Alder reaction/aromatization, and the removal protecting groups to afford (2S,3S)-pterosin C. The synthesis of (S)-pterosin D is started form commercially available D-(-)-pantolactone (118). D-(-)-pantolactone (118) is converted to vinyl iodide 125 that possess required functional group and chiral center at C2 and C3 of pterosin D. Vinyl iodide 125 is converted to diene 127 by Stille coupling reaction. Diene 127 is converted to diene-ynone intermediate using a similar synthetic sequence that is reported in section 3. Diene-ynone undergoes intramolecular Diels-Alder reaction/aromatization followed by removal protecting TBS groups to afford (S)-pterosin D.

    The second part of this thesis deals with the synthesis of Entecavir. In this part, intemediates were (-)-195 and (-)-204 from epoxy alcohol 193. Cyclization of either intermediate by NHK cyclization or radical cyclization will give triol intermediate as the precursor for the synthesis of Entecavir.
    ; zh
    探針;半合成螢光生物感測器 In recent years, scientists discover that proteins and metabolites are involved in many diseases. The concentration of proteins and metabolites often influence patient’s conditions. Therefore, methods which can detect concentration of proteins and metabolites are important in biology and medicine. Here we introduce two approach for the detection of proteins and metabolites, fluorescence sensor protein and fluorescence probe.
    Fluorescent sensor proteins offer the possibility to study the concentration of key metabolites in living cells. The approaches currently used to generate such fluorescent sensor proteins lack generality, as these sensors rely on a conformational change of a protein upon ligand binding to generate sinal. Here we devalope a strategy to overcome this limitation. We use a self-labeling protein tag to link with hCA to form SNAP-hCA. This recombinant protein was labeled with defferent synthetic moleculer containing BG group and fluorophore.
    In our fluorescent sensor protein, the metabolite of interest competes with labeling ligand. The fluorescence decrease, as the metabolite displaces the intramolecular ligand and makes the cyclic system open. The defference of readout can also be fitted with dose-response equation to obtain IC50. Furthermore, the modular design of our sensors provides a cyclic system that can change ligand binding protein or self-labeling protein. This adventage can let us detect defferent metabolite by aimply changing ligand binding protein in further approaches.
    In the second part, fluorescence probe containing a fluorophore and a ligand is designed to detact protein. Since the ligand part of fluorescence probe can specificly inhibit target protein, our probe can show a high specificity for target protein identification. Our fluorophore in this part not only has polarity sensitivity but also viscosity sensitivity. When the ligand part of our probe recognizes the binding site of target protein, the fluorophore will be closer to the binding pocket. Subsequently the fluorescent turn on, because of the restricted environment.
    ; en; zh
    蛋白質結構;核磁共振;鋅離子;mS100A4蛋白質 zh
    金屬增強螢光效應;金奈米粒子;共軛焦螢光顯微鏡;二氧化鈦 We research the fluorescence enhancement of Rose Bengal on the different distance between Rose Bengal and Gold nanoparticle. In this experiment, we use confocal microscopy to measure the fluorescence lifetime of dye on the single Gold nanoparticle. The medium between molecular and Gold nanoparticle are polymer or TiO2 coating on the surface of Gold nanoparticle. In the polymer coating, we use Poly Styrene Sulfonate (PSS) and Poly Allyamine Hydrochloride (PAH) to coat on the 70 nm of Gold nanoparticle by the Layer by Layer method. We coat 1 to 7 layers, and the thickness are 1.1 nm to 7.3 nm, the average of thickness is 1.05 nm per layer. The fluorescence lifetime are bi-exponent decay. The lifetime of TAU1 are 34 ps to 60 ps, and the lifetime of TAU2 are 282 ps to 368 ps from 1 layer to 7 layers. In the TiO2 coating, we modify the surface of Gold nanoparticle, then add Titanium isopropoxide (TTIP) to coat 5 nm, 10 nm, 15 nm and 20 nm of thickness with different reaction time. And the fluorescence lifetime are also bi-exponent decay. The sample coating from 5 nm to 20 nm, which TAU1 are 24 ps to 120 ps, TAU2 are 241 ps to 672 ps. Finally, we use the experiment result and some reference to propose the simple kinetic mechanism. The fluorescence enhancement are decrease when the distance increase. The fluorescence enhancement of dye are limited on the medium of TiO2, because the excited of dye can decay by electron transfer.; zh; en

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