論文使用權限 Thesis access permission:自定論文開放時間 user define
開放時間 Available:
校內 Campus: 已公開 available
校外 Off-campus: 已公開 available
論文名稱 Title |
疊氮化合物經由表面光化學反應合成偶氮化合物反應機構研究 Surface Photochemical Synthesis of Azoarenes from Aryl Azides |
||
系所名稱 Department |
|||
畢業學年期 Year, semester |
語文別 Language |
||
學位類別 Degree |
頁數 Number of pages |
70 |
|
研究生 Author |
|||
指導教授 Advisor |
|||
召集委員 Convenor |
|||
口試委員 Advisory Committee |
|||
口試日期 Date of Exam |
2018-07-20 |
繳交日期 Date of Submission |
2018-08-06 |
關鍵字 Keywords |
偶氮芳香烴化合物、表面、氮烯化合物、疊氮化合物、光解反應 azides, azoarenes, nitrenes, surface, photodissociation |
||
統計 Statistics |
本論文已被瀏覽 5634 次,被下載 0 次 The thesis/dissertation has been browsed 5634 times, has been downloaded 0 times. |
中文摘要 |
此研究主要在超高真空下以4-methoxyphenyl azide(4-MPA)吸附在Cu(100)表面上,探討其光化學反應,同時藉由反射式紅外光譜(RAIRS)和熱程控脫附儀(TPD)來鑑定。4-MPA分子是根據參考文獻的步驟合成出的。實驗中,在室溫下將4-MPA直接從樣品管中昇華,並經過氣道漏氣閥將其蒸氣導引進入到超高真空腔體中。 經由實驗得知,吸附在銅單晶上的疊氮化物,可以藉由熱化學、光化學和金屬催化反應,使其脫去兩個氮原子而形成氮烯化合物。而透過紫外光照射可以讓N = N雙鍵形成,形成偶氮芳香烴化合物分子。在實驗中所使用光源的波長分別為365 nm和405 nm;然而不同波長的光源會使得N-N2斷鍵的速率不同,其原因來自於照射光會激發金屬基板的電子並轉移至吸附分子的最低未佔用軌域,促使鍵的斷裂。光解後生成穩定的中間體imide和活潑的triplet nitrene,triplet nitrene會迅速偶合形成偶氮芳香烴化合物。 |
Abstract |
Thermal, photochemical and metal-facilitated routes to aryl nitrenes via the extrusion of dinitrogen from 4-methoxyphenyl azide adsorbed on a single crystal Cu(100) surface have been investigated using reflection-absorption infrared spectroscopy and temperature-programmed desorption in ultrahigh high vacuum. Only by irradiation with UV light can an N=N double bond be made, rendering azoarene. The azido precursors are transparent to the 365 nm and 405 nm photons employed in our experiments; therefore, the observed wavelength-dependent N-N2 bond dissociation rates suggest a photo-induced substrate-mediated electron attachment mechanism leading concurrently to stable coordinated imide intermediates, as well as transitory reactive triplet nitrene species attributable to the on-surface azo-dimer synthesis. |
目次 Table of Contents |
Table of Content Chapter 1. Introduction 1 1.1 Background. 1 1.2 Research Motivation 5 Chapter 2. Experimental Section 7 2.1 Ultrahigh vacuum (UHV) system 7 2.2 Surface 9 2.3 Reagents 10 2.4 Temperature-programmed desorption (TPD) 11 2.5 Reflection-absorption infrared spectroscopy (RAIRS) 12 2.6 Density functional theory (DFT) calculations 13 Chapter 3. Results 14 3.1 Synthesis and characterization of 4-methoxyphenyl azide (4-MPA) 14 3.2 Thermal and photochemical reactions of 4-MPA on Cu(100). 16 3.3 Coverage-dependent study of 4-MPA on Cu(100). 25 3.4 Identification of surface intermediates by density functional theory (DFT) calculations 31 3.5 Thermal and photochemical reactions of 2,6-difluorophenyl azide (2,6-DFPA) on Cu(100) 36 Chapter 4. Discussion and Conclusions 40 4.1 Possible reaction mechanisms for azoarene formation 40 4.2 Photodissociation mechanism: direct photolysis. 45 4.3 Photodissociation mechanism: dissociation by electron attachment 47 4.4 Conclusions 51 References 53 List of Figures Figure 1.1 Examples of organic bond-forming reactions which were pursued in the on-surface synthesis. 2 Figure 1.2 Colors of azoarenes, such as Allura red (1), Chrysoin resorcinol (2), Janus green (3), and Direct blue (4). 3 Figure 1.3 Butterfly-like motion of the azoarene-crown ether. A large alkali-metal cation is selectively captured by the cis-isomer. 3 Figure 1.4 Photo-regulation of the formation and dissociation of DNA duplexes with azobenzene labeled oligonucleotides. 4 Figure 1.5 Various reactions pathways for aryl azides. 6 Figure 2.1 Layout of the UHV system. 8 Figure 2.2 (Left) Cu (100) mounted on a heating/cooling element. (Right) LEED pattern of Cu (100). Electron beam energy = 150 eV. 9 Figure 3.1 1HNMR spectrum of 4-MPA (400 MHz, CDCl3) Δ6.94 – 6.97 (d, H (H1, H3)), 6.87 – 6.90 (m, ΔH (H2, H4)), 3.79 (s, ΔH (H5)). 15 Figure 3.2 (a) Standard mass pattern of 4-MPA from NIST Chemistry WebBook. (b) Mass spectrum of 4-MPA characterized by our QMS. 15 Figure 3.3 Temperature-dependent RAIR spectra: (a) after adsorption of 1.0 L 4-MPA on Cu(100) at 100 K, (b) followed by 250 K anneal, and (c) followed by 650 K anneal. 17 Figure 3.4 Multiplex TPD spectra after adsorption of 1.0 L 4-MPA on Cu(100) at 100 K. 18 Figure 3.5 RAIR spectra: (a) after adsorption of 1.0 L 4-MPA on Cu(100) at 100 K, (b) (a) subjected to 10 minutes UV irradiation and (c)-(e) followed by annealing to 300 K, 500 K and 650 K. 19 Figure 3.6 Post-irradiation TPD spectra after adsorption of 1.0 L 4-MPA at 100 K on Cu(100) followed by UV illumination. 20 Figure 3.7 RAIR spectra of 4-MPA subjected to photolysis by 365 nm and 405 nm photoirradiation. 22 Figure 3.8 QMS response as a function of irradiation time. The synchronous rise-and-fall pattern of m/z 28 and 14 indictes the release of N2 due to photolysis of the adsorbed 4-MPA. The lack m/z 149 signals indicates there is no molecular photodesoprtion. 23 Figure 3.9 Photo-ejected N2 decay profiles fitted by exponential functions to extract the kinetic information. 24 Figure 3.10 Side-by-side comparison of PITPD for 1 L 4-MPA after by 365 nm and 405 nm UV light exposure for 10 minutes. 24 Figure 3.11 The coverage-dependent TPD spectra of m/z 149 after 0.5 L, 1.0 L, 2.0 L and 3.0 L 4-MPA exposures. 26 Figure 3.12 The coverage-dependent TPD spectra of m/z 123 for final aniline product after 0.5 L, 1.0 L, 2.0 L, 3.0 L and 4.0 L 4-MPA exposures. 27 Figure 3.13 The coverage-dependent RAIR spectra at various 4-MPA exposures. 28 Figure 3.14 The coverage-dependent post-irradiation TPD experiments of azoarene product (m/z 242) after 0.5 L, 1.0 L, 2.0 L, 3.0 L and 4.0 L 4-MPA exposures. 29 Figure 3.15 The coverage-dependent post-irradiation RAIR spectra as a function of 4-MPA exposures. 30 Figure 3.16 (a) RAIR spectra of surface species isolated by dissociatively adsorbing 4-MPA at 250 K on Cu(100), (b) computed IR spectrum of NAr moiety coordinated to single-layer Cu25 cluster, and (c) optimized Cu25NAr structure. 32 Figure 3.17 (a) RAIR spectrum taken right after 365 nm UV irradiation for 1.0 L 4-MPA on Cu(100) at 100 K, (b) (a) subjected to 500 K anneal, (c) difference spectrum between Figure 3.17 (a) and (b), and (d) DFT calculated spectrum of trans-azoarene on Cu25, and (e) optimized Cu25-(trans)ArN=NAr structure. 34 Figure 3.18 Mass spectrum of 2,6-DFPA characterized by QMS. 36 Figure 3.19 (a) Experimental RAIR spectrum after 1.0 L 2,6-DFPA adsorption on Cu (100), (b) and (c) Post-irradiation RAIR spectra after UV 365 nm and 405 nm illumination, respectively, and (d) RAIR spectrum after 1.0 L 2,6-DFPA adsorption at 250 K on Cu (100). 38 Figure 3.20 TPD spectrum after 1.0 L 2,6-DFPA adsorption on Cu(100) at 100 K. 39 Figure 3.21 Comparison of 2,6-DFPA PITPD by utilizing 365 nm and 405 nm UV irradiation, respectively. 39 Figure 4.1 (a) Post-irradiation TPD spectrum at 250 K adsorption of 1.0 L 2,6-DFPA. (b) 1.0 L 2,6-DFPA adsorbed at 100K. 42 Figure 4.2 (a) PITPD spectra of three possible azoarenes taken after co-adsorption of 0.5 L 4-MPA and 0.5 L 2,6-DFPA/Cu(100). (b) PITPD spectra of self-coupled and cross-coupled azoarenes taken after sequential adsorption of 1.0 L 4-MPA at 250 K and 0.5 L 2,6-DFPA at 100 K/Cu(100). 43 Figure 4.3 Calculated frontier orbitals of 4-MPA. 46 Figure 4.4 The UV-vis spectrum of 4-MPA diluted in ethyl acetate (EA) with a volume ratio of 0.001. 46 Scheme 4.1 Pathway involving bimolecular coupling of metal imide species. 40 Scheme 4.2 Pathway involving cycloaddition of aryl azide to metal imide to form a reactive metal-tetrazene species. 41 Scheme 4.3 Pathway involving rapid dimerization of triplet nitrene species. 44 Scheme 4.4 photo-induced substrate-mediate electron attachment processes and potential energy curves along the reaction coordinates. 50 |
參考文獻 References |
1. Shen, Q.; Gao, H.-Y.; Fuchs, H., Frontiers of on-surface synthesis: from principles to applications. Nano Today 2017, 13, 77-96. 2. Cai, J.; Ruffieux, P.; Jaafar, R.; Bieri, M.; Braun, T.; Blankenburg, S.; Muoth, M.; Seitsonen, A. P.; Saleh, M.; Feng, X., Atomically precise bottom-up fabrication of graphene nanoribbons. Nature 2010, 466 (7305), 470. 3. Grill, L.; Dyer, M.; Lafferentz, L.; Persson, M.; Peters, M. V.; Hecht, S., Nano-architectures by covalent assembly of molecular building blocks. Nat. Nanotechnol. 2007, 2 (11), 687. 4. Lafferentz, L.; Ample, F.; Yu, H.; Hecht, S.; Joachim, C.; Grill, L., Conductance of a single conjugated polymer as a continuous function of its length. Science 2009, 323 (5918), 1193-1197. 5. Lafferentz, L.; Eberhardt, V.; Dri, C.; Africh, C.; Comelli, G.; Esch, F.; Hecht, S.; Grill, L., Controlling on-surface polymerization by hierarchical and substrate-directed growth. Nat. Chem. 2012, 4 (3), 215. 6. Bebensee, F.; Bombis, C.; Vadapoo, S.-R.; Cramer, J. R.; Besenbacher, F.; Gothelf, K. V.; Linderoth, T. R., On-Surface Azide–Alkyne Cycloaddition on Cu (111): Does It “Click” in Ultrahigh Vacuum? J. Am. Chem. Soc. 2013, 135 (6), 2136-2139. 7. Diaz Arado, O.; Mönig, H.; Wagner, H.; Franke, J. r.-H.; Langewisch, G.; Held, P. A.; Studer, A.; Fuchs, H., On-surface azide–alkyne cycloaddition on Au (111). ACS nano 2013, 7 (10), 8509-8515. 8. Kanuru, V. K.; Kyriakou, G.; Beaumont, S. K.; Papageorgiou, A. C.; Watson, D. J.; Lambert, R. M., Sonogashira coupling on an extended gold surface in vacuo: reaction of phenylacetylene with iodobenzene on Au (111). J. Am. Chem. Soc. 2010, 132 (23), 8081-8086. 9. Sánchez-Sánchez, C.; Yubero, F.; González-Elipe, A. R.; Feria, L.; Sanz, J. F. n.; Lambert, R. M., The Flexible surface revisited: adsorbate-induced reconstruction, homocoupling, and Sonogashira cross-coupling on the Au (100) surface. J. Phys. Chem. C 2014, 118 (22), 11677-11684. 10. Gnanamani, A.; Bhaskar, M.; Ganeshjeevan, R.; Chandrasekar, R.; Sekaran, G.; Sadulla, S.; Radhakrishnan, G., Enzymatic and chemical catalysis of xylidine ponceau 2R and evaluation of products released. Process Biochem. 2005, 40 (11), 3497-3504. 11. Kamboh, M. A.; Solangi, I. B.; Sherazi, S.; Memon, S., Synthesis and application of calix [4] arene based resin for the removal of azo dyes. J. Hazard. Mater. 2009, 172 (1), 234-239. 12. Rovina, K.; Siddiquee, S.; Shaarani, S. M., Extraction, analytical and advanced methods for detection of allura red AC (E129) in food and beverages products. Front. Microbiol. 2016, 7, 798. 13. Niamlang, P.; Supaphol, P.; Morlock, G. E., Performance of Electropun Polyacrylonitrile Nanofibrous Phases, Shown for the Separation of Water-Soluble Food Dyes via UTLC-Vis-ESI-MS. Nanomaterials 2017, 7 (8), 218. 14. Lazarow, A.; Cooperstein, S., Studies on the mechanism of Janus Green B staining of mitochondria: I. Review of the literature. Exp. Cell. Res. 1953, 5 (1), 56-69. 15. Amin, N. K., Removal of direct blue-106 dye from aqueous solution using new activated carbons developed from pomegranate peel: adsorption equilibrium and kinetics. J. Hazard. Mater. 2009, 165 (1-3), 52-62. 16. Merino, E., Synthesis of azobenzenes: the coloured pieces of molecular materials. Chem. Soc. Rev. 2011, 40 (7), 3835-3853. 17. Yagai, S.; Karatsu, T.; Kitamura, A., Photocontrollable self‐assembly. Chem. Eur. J 2005, 11 (14), 4054-4063. 18. Shinkai, S.; Nakaji, T.; Ogawa, T.; Shigematsu, K.; Manabe, O., Photoresponsive crown ethers. 2. Photocontrol of ion extraction and ion transport by a bis (crown ether) with a butterfly-like motion. J. Am. Chem. Soc. 1981, 103 (1), 111-115. 19. Asanuma, H.; Takarada, T.; Yoshida, T.; Tamaru, D.; Liang, X.; Komiyama, M., Enantioselective incorporation of azobenzenes into oligodeoxyribonucleotide for effective photoregulation of duplex formation. Angew. Chem. 2001, 113 (14), 2743-2745. 20. Takarada, T.; Tamaru, D.; Liang, X.; Asanuma, H.; Komiyama, M., l-threoninol as a chiral linker of azobenzene for the effective photo-regulation of DNA triplex formation. Chem. Lett. 2001, 30 (7), 732-733. 21. Gritsan, N. P.; Tigelaar, D.; Platz, M. S., A laser flash photolysis study of some simple para-substituted derivatives of singlet phenyl nitrene. J. Phys. Chem. A 1999, 103 (23), 4465-4469. 22. Born, R.; Burda, C.; Senn, P.; Wirz, J., Transient Absorption Spectra and Reaction Kinetics of Singlet Phenylnitrene and Its 2, 4, 6-Tribromo Derivative in Solution. J. Am. Chem. Soc. 1997, 119 (21), 5061-5062. 23. Gritsan, N. P.; Yuzawa, T.; Platz, M. S., Direct observation of singlet phenylnitrene and measurement of its rate of rearrangement. J. Am. Chem. Soc. 1997, 119 (21), 5059-5060. 24. Gritsan, N. P.; Zhu, Z.; Hadad, C. M.; Platz, M. S., Laser flash photolysis and computational study of singlet phenylnitrene. J. Am. Chem. Soc. 1999, 121 (6), 1202-1207. 25. Karney, W. L.; Borden, W. T., Ab initio study of the ring expansion of phenylnitrene and comparison with the ring expansion of phenylcarbene. J. Am. Chem. Soc. 1997, 119 (6), 1378-1387. 26. Karney, W. L.; Borden, W. T., Why Does o-Fluorine Substitution Raise the Barrier to Ring Expansion of Phenylnitrene? J. Am. Chem. Soc. 1997, 119 (14), 3347-3350. 27. Takaoka, A.; Moret, M.-E.; Peters, J. C., A Ru (I) metalloradical that catalyzes nitrene coupling to azoarenes from arylazides. J. Am. Chem. Soc. 2012, 134 (15), 6695-6706. 28. Powers, I. G.; Andjaba, J. M.; Luo, X.; Mei, J.; Uyeda, C., Catalytic Azoarene Synthesis from Aryl Azides Enabled by a Dinuclear Ni Complex. J. Am. Chem. Soc. 2018, 140 (11), 4110-4118. 29. Li, Y.; Wong, W.-T., Low valent transition metal clusters containing nitrene/imido ligands. Coord. Chem. Rev. 2003, 243 (1-2), 191-212. 30. Firestone, R. A., Mechanism of 1, 3-dipolar cycloadditions. J. Org. Chem. 1968, 33 (6), 2285-2290. 31. Hollerer, M.; Lüftner, D.; Hurdax, P.; Ules, T.; Soubatch, S.; Tautz, F. S.; Koller, G.; Puschnig, P.; Sterrer, M.; Ramsey, M. G., Charge Transfer and Orbital Level Alignment at Inorganic/Organic Interfaces: The Role of Dielectric Interlayers. ACS nano 2017, 11 (6), 6252-6260. 32. Knoesel, E.; Hotzel, A.; Wolf, M., Ultrafast dynamics of hot electrons and holes in copper: Excitation, energy relaxation, and transport effects. Phys. Rev. B 1998, 57 (20), 12812. 33. Ukraintsev, V. A.; Long, T. J.; Harrison, I., Photofragmentation dynamics of submonolayers of CH3Br adsorbed on Pt(111). J. Chem. Phys 1992, 96 (5), 3957-3965. 34. Lang, N. D.; Kohn, W., Theory of Metal Surfaces: Induced Surface Charge and Image Potential. Phys. Rev. B 1973, 7 (8), 3541-3550. 35. Council, N. R., Digest of Literature on Dielectrics. National Academy of Sciences, National Research Council: 1971. 36. Gartland, P.; Berge, S.; Slagsvold, B., Photoelectric work function of a copper single crystal for the (100),(110),(111), and (112) faces. Phys. Rev. Lett. 1972, 28 (12), 738. 37. Witte, G.; Lukas, S.; Bagus, P. S.; Wöll, C., Vacuum level alignment at organic/metal junctions:“Cushion” effect and the interface dipole. Appl. Phys. Lett. 2005, 87 (26), 263502. 38. Held, P. A.; Fuchs, H.; Studer, A., Covalent‐Bond Formation via On‐Surface Chemistry. Chem. Eur. J 2017, 23 (25), 5874-5892. |
電子全文 Fulltext |
本電子全文僅授權使用者為學術研究之目的,進行個人非營利性質之檢索、閱讀、列印。請遵守中華民國著作權法之相關規定,切勿任意重製、散佈、改作、轉貼、播送,以免觸法。 論文使用權限 Thesis access permission:自定論文開放時間 user define 開放時間 Available: 校內 Campus: 已公開 available 校外 Off-campus: 已公開 available |
紙本論文 Printed copies |
紙本論文的公開資訊在102學年度以後相對較為完整。如果需要查詢101學年度以前的紙本論文公開資訊,請聯繫圖資處紙本論文服務櫃台。如有不便之處敬請見諒。 開放時間 available 已公開 available |
QR Code |